1.
Absolute dating
–
Absolute dating is the process of determining an age on a specified chronology in archaeology and geology. Some scientists prefer the terms chronometric or calendar dating, as use of the word implies a unwarranted certainty of accuracy. Absolute dating provides an age or range in contrast with relative dating which places events in order without any measure of the age between events. Techniques include tree rings in timbers, radiocarbon dating of wood or bones, radiometric dating is based on the known and constant rate of decay of radioactive isotopes into their radiogenic daughter isotopes. Particular isotopes are suitable for different applications due to the type of atoms present in the mineral or other material, one of the most widely used and well-known absolute dating techniques is carbon-14 dating, which is used to date organic remains. This is a technique since it is based on radioactive decay. Cosmic radiation entering the earth’s atmosphere produces carbon-14, and plants take in carbon-14 as they fix carbon dioxide, carbon-14 moves up the food chain as animals eat plants and as predators eat other animals. With death, the uptake of carbon-14 stops and it takes 5,730 years for half the carbon-14 to change to nitrogen, this is the half-life of carbon-14. After another 5,730 years only one-quarter of the original carbon-14 will remain, after yet another 5,730 years only one-eighth will be left. By measuring the carbon-14 in organic material, scientists can determine the date of death of the matter in an artifact or ecofact. The relatively short half-life of carbon-14,5,730 years, an additional problem with carbon-14 dates from archeological sites is known as the old wood problem. Thus dating that particular tree does not necessarily indicate when the fire burned or the structure was built, for this reason, many archaeologists prefer to use samples from short-lived plants for radiocarbon dating. The development of mass spectrometry dating, which allows a date to be obtained from a very small sample, has been very useful in this regard. Other radiometric dating techniques are available for earlier periods, one of the most widely used is potassium-argon dating. Potassium-40 is an isotope of potassium that decays into argon-40. The half-life of potassium-40 is 1.3 billion years, far longer than that of carbon-14, potassium is common in rocks and minerals, allowing many samples of geochronological or archeological interest to be dated. Argon, a gas, is not commonly incorporated into such samples except when produced in situ through radioactive decay. The date measured reveals the last time that the object was heated past the closure temperature at which the trapped argon can escape the lattice, k-Ar dating was used to calibrate the geomagnetic polarity time scale
Absolute dating
–
The growth rings of a tree at
Bristol Zoo, England. Each ring represents one year; the outside rings, near the bark, are the youngest.
2.
Megaannum
–
A year is the orbital period of the Earth moving in its orbit around the Sun. Due to the Earths axial tilt, the course of a year sees the passing of the seasons, marked by changes in weather, the hours of daylight, and, consequently, vegetation and soil fertility. In temperate and subpolar regions around the globe, four seasons are recognized, spring, summer, autumn. In tropical and subtropical regions several geographical sectors do not present defined seasons, but in the seasonal tropics, a calendar year is an approximation of the number of days of the Earths orbital period as counted in a given calendar. The Gregorian, or modern, calendar, presents its calendar year to be either a common year of 365 days or a year of 366 days, as do the Julian calendars. For the Gregorian calendar the average length of the year across the complete leap cycle of 400 years is 365.2425 days. The ISO standard ISO 80000-3, Annex C, supports the symbol a to represent a year of either 365 or 366 days, in English, the abbreviations y and yr are commonly used. In astronomy, the Julian year is a unit of time, it is defined as 365.25 days of exactly 86400 seconds, totalling exactly 31557600 seconds in the Julian astronomical year. The word year is used for periods loosely associated with, but not identical to, the calendar or astronomical year, such as the seasonal year, the fiscal year. Similarly, year can mean the period of any planet, for example. The term can also be used in reference to any long period or cycle, west Saxon ġēar, Anglian ġēr continues Proto-Germanic *jǣran. Cognates are German Jahr, Old High German jār, Old Norse ár and Gothic jer, all the descendants of the Proto-Indo-European noun *yeh₁rom year, season. Cognates also descended from the same Proto-Indo-European noun are Avestan yārǝ year, Greek ὥρα year, season, period of time, Old Church Slavonic jarŭ, Latin annus is from a PIE noun *h₂et-no-, which also yielded Gothic aþn year. Both *yeh₁-ro- and *h₂et-no- are based on verbal roots expressing movement, *h₁ey- and *h₂et- respectively, the Greek word for year, ἔτος, is cognate with Latin vetus old, from the PIE word *wetos- year, also preserved in this meaning in Sanskrit vat-sa- yearling and vat-sa-ras year. Derived from Latin annus are a number of English words, such as annual, annuity, anniversary, etc. per annum means each year, anno Domini means in the year of the Lord. No astronomical year has an number of days or lunar months. Financial and scientific calculations often use a 365-day calendar to simplify daily rates, in the Julian calendar, the average length of a year is 365.25 days. In a non-leap year, there are 365 days, in a year there are 366 days
Megaannum
–
Key concepts
3.
Quaternary
–
Quaternary is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy. It follows the Neogene Period and spans from 2.588 ±0.005 million years ago to the present, the Quaternary Period is divided into two epochs, the Pleistocene and the Holocene. The informal term Late Quaternary refers to the past 0. 5–1.0 million years, the Quaternary Period is typically defined by the cyclic growth and decay of continental ice sheets driven by Milankovitch cycles and the associated climate and environmental changes that occurred. The term Quaternary was proposed by Giovanni Arduino in 1759 for alluvial deposits in the Po River valley in northern Italy and it was introduced by Jules Desnoyers in 1829 for sediments of Frances Seine Basin that seemed clearly to be younger than Tertiary Period rocks. The Quaternary Period follows the Neogene Period and extends to the present, the Quaternary covers the time span of glaciations classified as the Pleistocene, and includes the present interglacial time-period, the Holocene. This places the start of the Quaternary at the onset of Northern Hemisphere glaciation approximately 2.6 million years ago, Quaternary stratigraphers usually worked with regional subdivisions. From the 1970s, the International Commission on Stratigraphy tried to make a single geologic time scale based on GSSPs, the Quaternary subdivisions were defined based on biostratigraphy instead of paleoclimate. This led to the problem that the base of the Pleistocene was at 1.805 Mya. The ICS then proposed to use of the name Quaternary altogether. The Anthropocene has been proposed as an epoch as a mark of the anthropogenic impact on the global environment starting with the Industrial Revolution. The Anthropocene is not officially designated by the ICS, however, the 2.6 million years of the Quaternary represents the time during which recognizable humans existed. Over this short period, there has been relatively little change in the distribution of the continents due to plate tectonics. The Quaternary geological record is preserved in detail than that for earlier periods. The climate was one of periodic glaciations with continental glaciers moving as far from the poles as 40 degrees latitude, there was a major extinction of large mammals in Northern areas at the end of the Pleistocene Epoch. Many forms such as saber-toothed cats, mammoths, mastodons, glyptodonts, others, including horses, camels and American cheetahs became extinct in North America. Glaciation took place repeatedly during the Quaternary Ice Age – a term coined by Schimper in 1839 that began with the start of the Quaternary about 2.58 Mya and continues to the present-day. In 1821, a Swiss engineer, Ignaz Venetz, presented an article in which he suggested the presence of traces of the passage of a glacier at a distance from the Alps. This idea was initially disputed by another Swiss scientist, Louis Agassiz, a year later, Agassiz raised the hypothesis of a great glacial period that would have had long-reaching general effects
Quaternary
–
Artist's impression of Earth during the
Last Glacial Maximum
Quaternary
–
Biogeography
4.
Pleistocene
–
The Pleistocene is the geological epoch which lasted from about 2,588,000 to 11,700 years ago, spanning the worlds most recent period of repeated glaciations. The end of the Pleistocene corresponds with the end of the last glacial period, the Pleistocene is the first epoch of the Quaternary Period or sixth epoch of the Cenozoic Era. In the ICS timescale, the Pleistocene is divided into four stages or ages, all of these stages were defined in southern Europe. In addition to this subdivision, various regional subdivisions are often used. Charles Lyell introduced the term pleistocene in 1839 to describe strata in Sicily that had at least 70% of their molluscan fauna still living today and this distinguished it from the older Pliocene Epoch, which Lyell had originally thought to be the youngest fossil rock layer. The Pleistocene has been dated from 2.588 million to 11,700 years before present and it covers most of the latest period of repeated glaciation, up to and including the Younger Dryas cold spell. The end of the Younger Dryas has been dated to about 9640 BC, the IUGS has yet to approve a type section, Global Boundary Stratotype Section and Point, for the upper Pleistocene/Holocene boundary. The proposed section is the North Greenland Ice Core Project ice core 75°06 N 42°18 W, the lower boundary of the Pleistocene Series is formally defined magnetostratigraphically as the base of the Matuyama chronozone, isotopic stage 103. Above this point there are notable extinctions of the calcareous nanofossils, Discoaster pentaradiatus, the Pleistocene covers the recent period of repeated glaciations. The name Plio-Pleistocene has, in the past, been used to mean the last ice age. The revised definition of the Quaternary, by pushing back the date of the Pleistocene to 2.58 Ma. Pleistocene climate was marked by repeated glacial cycles in which continental glaciers pushed to the 40th parallel in some places and it is estimated that, at maximum glacial extent, 30% of the Earths surface was covered by ice. In addition, a zone of permafrost stretched southward from the edge of the sheet, a few hundred kilometres in North America. The mean annual temperature at the edge of the ice was −6 °C, during interglacial times, such as at present, drowned coastlines were common, mitigated by isostatic or other emergent motion of some regions. The effects of glaciation were global, antarctica was ice-bound throughout the Pleistocene as well as the preceding Pliocene. The Andes were covered in the south by the Patagonian ice cap, there were glaciers in New Zealand and Tasmania. The current decaying glaciers of Mount Kenya, Mount Kilimanjaro, glaciers existed in the mountains of Ethiopia and to the west in the Atlas mountains. In the northern hemisphere, many glaciers fused into one, the Cordilleran ice sheet covered the North American northwest, the east was covered by the Laurentide
Pleistocene
–
The maximum extent of
glacial ice in the north polar area during the Pleistocene period.
Pleistocene
–
Ice ages as reflected in atmospheric CO 2, stored in bubbles from glacial ice of
Antarctica.
Pleistocene
–
Pleistocene of
Northern Spain showing
woolly mammoth,
cave lions eating a
reindeer,
tarpans, and
woolly rhinoceros.
Pleistocene
–
Pleistocene of
South America showing
Megatherium and two
Glyptodon.
5.
Neogene
–
The Neogene is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period 23.03 million years ago to the beginning of the present Quaternary Period 2.58 Mya. The Neogene is sub-divided into two epochs, the earlier Miocene and the later Pliocene, some geologists assert that the Neogene cannot be clearly delineated from the modern geological period, the Quaternary. During this period, mammals and birds continued to evolve into modern forms. Early hominids, the ancestors of humans, appeared in Africa near the end of the period, some continental movement took place, the most significant event being the connection of North and South America at the Isthmus of Panama, late in the Pliocene. This cut off the ocean currents from the Pacific to the Atlantic ocean. The global climate cooled considerably over the course of the Neogene, the terms Neogene System and upper Tertiary System describe the rocks deposited during the Neogene Period. The continents in the Neogene were very close to their current positions, the Isthmus of Panama formed, connecting North and South America. The Indian subcontinent continued to collide with Asia, forming the Himalayas, sea levels fell, creating land bridges between Africa and Eurasia and between Eurasia and North America. The global climate became seasonal and continued an overall drying and cooling trend which began at the start of the Paleogene. The ice caps on both poles began to grow and thicken, and by the end of the period the first of a series of glaciations of the current Ice Age began, marine and continental flora and fauna have a modern appearance. The reptile group Choristodera became extinct in the part of the period. Mammals and birds continued to be the dominant terrestrial vertebrates, the first hominids, the ancestors of humans, appeared in Africa and spread into Eurasia. In response to the cooler, seasonal climate, tropical plant species gave way to deciduous ones, grasses therefore greatly diversified, and herbivorous mammals evolved alongside it, creating the many grazing animals of today such as horses, antelope, and bison. The Neogene traditionally ended at the end of the Pliocene Epoch, just before the definition of the beginning of the Quaternary Period. However, there was a movement amongst geologists to also include ongoing geological time in the Neogene, by dividing the Cenozoic Era into three periods instead of seven epochs, the periods are more closely comparable to the duration of periods in the Mesozoic and Paleozoic eras. The International Commission on Stratigraphy once proposed that the Quaternary be considered a sub-era of the Neogene, with a date of 2.58 Ma. In the 2004 proposal of the ICS, the Neogene would have consisted of the Miocene and Pliocene epochs, thus the Neogene Period ends bounding the succeeding Quaternary Period at 2.58 Mya. Digital Atlas of Neogene Life for the Southeastern United States — by San Jose State University via Web Archive
Neogene
–
Scene featuring Miocene (Early Neogene) fauna
6.
Miocene
–
The Miocene is the first geological epoch of the Neogene Period and extends from about 23.03 to 5.333 million years ago. The Miocene was named by Sir Charles Lyell and its name comes from the Greek words μείων and καινός and means less recent because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene Epoch and is followed by the Pliocene Epoch, the earth went from the Oligocene through the Miocene and into the Pliocene, with the climate slowly cooling towards a series of ice ages. The Miocene boundaries are not marked by a single distinct global event, the apes arose and diversified during the Miocene, becoming widespread in the Old World. By the end of this epoch, the ancestors of humans had split away from the ancestors of the chimpanzees to follow their own evolutionary path, as in the Oligocene before it, grasslands continued to expand and forests to dwindle in extent. In the Miocene seas, kelp forests made their first appearance, the plants and animals of the Miocene were fairly modern. The Miocene faunal stages from youngest to oldest are typically named according to the International Commission on Stratigraphy, Two subdivisions each form the lower, middle, continents continued to drift toward their present positions. Mountain building took place in western North America, Europe, both continental and marine Miocene deposits are common worldwide with marine outcrops common near modern shorelines. Well studied continental exposures occur in the North American Great Plains, India continued to collide with Asia, creating dramatic new mountain ranges. The Tethys Seaway continued to shrink and then disappeared as Africa collided with Eurasia in the Turkish–Arabian region between 19 and 12 Ma. The subsequent uplift of mountains in the western Mediterranean region and a fall in sea levels combined to cause a temporary drying up of the Mediterranean Sea near the end of the Miocene. The global trend was towards increasing aridity caused primarily by global cooling reducing the ability of the atmosphere to absorb moisture, climates remained moderately warm, although the slow global cooling that eventually led to the Pleistocene glaciations continued. Although a long-term cooling trend was well underway, there is evidence of a period during the Miocene when the global climate rivalled that of the Oligocene. The Miocene warming began 21 million years ago and continued until 14 million years ago, by 8 million years ago, temperatures dropped sharply once again, and the Antarctic ice sheet was already approaching its present-day size and thickness. Greenland may have begun to have large glaciers as early as 7 to 8 million years ago, life during the Miocene Epoch was mostly supported by the two newly formed biomes, kelp forests and grasslands. This allows for more grazers, such as horses, rhinoceroses, ninety five percent of modern plants existed by the end of this epoch. The higher organic content and water retention of the deeper and richer grassland soils, with long term burial of carbon in sediments, produced a carbon and this, combined with higher surface albedo and lower evapotranspiration of grassland, contributed to a cooler, drier climate. The expansion of grasslands and radiations among terrestrial herbivores correlates to fluctuations in CO2
Miocene
–
The
dragon blood tree is considered a remnant of the Mio-Pliocene Laurasian subtropical forests that are now almost extinct in North Africa.
Miocene
–
Cameloid footprint (Lamaichnum alfi Sarjeant and Reynolds, 1999; convex hyporelief) from the
Barstow Formation (Miocene) of Rainbow Basin, California.
Miocene
–
Miocene fauna of North America
Miocene
–
A Miocene crab (Tumidocarcinus giganteus) from the collection of the
Children's Museum of Indianapolis
7.
Messinian
–
The Messinian is in the geologic timescale the last age or uppermost stage of the Miocene. It spans the time between 7.246 ±0.005 Ma and 5.333 ±0.005 Ma and it follows the Tortonian and is followed by the Zanclean, the first age of the Pliocene. The Messinian overlaps the Turolian European Land Mammal Mega Zone and the Pontian Central European Paratethys stage and it also overlaps the late Huayquerian and early Montehermosan South American Land Mammal Ages, and falls inside the more extensive Hemphillian North American Land Mammal Age. During the Messinian, around 6 million years ago, the Messinian salinity crisis took place, the Messinian was introduced by Swiss stratigrapher Karl Mayer-Eymar in 1867. Its name comes from the Italian city of Messina on Sicily, the base of the Messinian is at the first appearance of the planktonic foram species Globorotalia conomiozea and is stratigraphically in the middle of magnetic chronozone C3Br. 1r. The Global Boundary Stratotype Section and Point for the Messinian is located in a section at Oued Akrech, the top of the Messinian lies with the top of magnetic chronozone Cr3. The top is also close to the level of the calcareous nanoplankton species Triquetrorhabdulus rugosus. Hilgen, F. J. S. Iaccarino, W. Krijgsman, G. Villa, the Global Boundary Stratotype Section and Point of the Messinian Stage. Catalogue systématique et descriptif des fossiles des terrains tertiaires qui se trouvent du Musée fédéral de Zürich
Messinian
–
Messinian
gypsum and
clay deposits in the
Sorbas basin near
Sorbas, southern
Spain. Evaporite deposits of Messinian age are common throughout the
Mediterranean.
8.
Langhian
–
The Langhian is, in the ICS geologic timescale, an age or stage in the middle Miocene epoch/series. It spans the time between 15.97 ±0.05 Ma and 13.65 ±0.05 Ma during the Middle Miocene. The Langhian was a continuing warming period defined by Lorenzo Pareto in 1865, it was established in the Langhe area north of Ceva in northern Italy. The Langhian is preceded by the Burdigalian and followed by the Serravallian stage, the base of the Langhian is defined by the first appearance of foraminifer species Praeorbulina glomerosa and is also coeval with the top of magnetic chronozone C5Cn. 1n. A GSSP for the Langhian stage was not yet established in 2009, & Smith, A. G.2004, A Geologic Time Scale 2004, Cambridge University Press. Pareto, L.1865, Note sur les subdivisions que lon pourrait établir dans les terrains tertaires de lApennin septentrional, Bulletin de la Societé Géologique de France 2, p. 210-277
Langhian
–
Grizzled Giant Squirrel, Ratufa macroura. Its
genus was probably already distinct in the Langhian.
9.
Paleogene
–
The Paleogene is a geologic period and system that spans 43 million years from the end of the Cretaceous Period 66 million years ago to the beginning of the Neogene Period 23.03 Mya. It is the beginning of the Cenozoic Era of the present Phanerozoic Eon and this period consists of the Paleocene, Eocene and Oligocene epochs. The terms Paleogene System and lower Tertiary System are applied to the rocks deposited during the Paleogene Period. By dividing the Tertiary Period into two periods instead of directly into five epochs, the periods are more comparable to the duration of periods of the preceding Mesozoic and Paleozoic Eras. The trend was caused by the formation of the Antarctic Circumpolar Current. During the Paleogene, the continued to drift closer to their current positions. India was in the process of colliding with Asia, subsequently forming the Himalayas, the Atlantic Ocean continued to widen by a few centimeters each year. Africa was moving north to meet with Europe and form the Mediterranean, inland seas retreated from North America early in the period. Australia had also separated from Antarctica and was drifting towards Southeast Asia, mammals began a rapid diversification during this period. Some of these mammals would evolve into forms that would dominate the land, while others would become capable of living in marine, specialized terrestrial. Those that took to the oceans became modern cetaceans, while those that took to the trees became primates, the group to which humans belong. Birds, which were well established by the end of the Cretaceous. In comparison to birds and mammals, most other branches of life remained unchanged during this period. As the Earth cooled, tropical plants became less numerous and were now restricted to equatorial regions, deciduous plants, which could survive through the seasonal climates the world was now experiencing, became more common. The Paleogene is notable in the context of offshore oil drilling, and especially in Gulf of Mexico oil exploration and these rock formations represent the current cutting edge of deep-water oil discovery. Lower Tertiary explorations to date include, Kaskida Oil Field Tiber Oil Field Jack 2 Paleogene Microfossils, 180+ images of Foraminifera
Paleogene
–
Scene featuring typical Eocene (Mid-Paleogene) flora and fauna
10.
Oligocene
–
The Oligocene is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present. As with other geologic periods, the rock beds that define the epoch are well identified but the exact dates of the start. The name Oligocene comes from the Ancient Greek ὀλίγος and καινός, the Oligocene is preceded by the Eocene Epoch and is followed by the Miocene Epoch. The Oligocene is the third and final epoch of the Paleogene Period, the Oligocene is often considered an important time of transition, a link between the archaic world of the tropical Eocene and the more modern ecosystems of the Miocene. Major changes during the Oligocene included an expansion of grasslands. By contrast, the Oligocene–Miocene boundary is not set at an easily identified worldwide event, Oligocene faunal stages from youngest to oldest are, The Paleogene Period general temperature decline is interrupted by an Oligocene 7-million-year stepwise climate change. A deeper 8.2 °C,400, 000-year temperature depression leads the 2 °C, the stepwise climate change began 32.5 Ma and lasted through to 25.5 Ma, as depicted in the PaleoTemps chart. The Oligocene climate change was a increase in ice volume. The 7-million-year depression abruptly terminated within 1–2 million years of the La Garita Caldera eruption at 28–26 Ma, a deep 400, 000-year glaciated Oligocene Miocene boundary event is recorded at McMurdo Sound and King George Island. During this epoch, the continued to drift toward their present positions. Antarctica became more isolated and finally developed an ice cap, a brief marine incursion marks the early Oligocene in Europe. Marine fossils from the Oligocene are rare in North America, there appears to have been a land bridge in the early Oligocene between North America and Europe, since the faunas of the two regions are very similar. Sometime during the Oligocene, South America was finally detached from Antarctica and it also allowed the Antarctic Circumpolar Current to flow, rapidly cooling the Antarctic continent. Angiosperms continued their expansion throughout the world as tropical and sub-tropical forests were replaced by deciduous forests. Open plains and deserts became more common and grasses expanded from their habitat in the Eocene moving out into open tracts. However, even at the end of the period, grass was not quite enough for modern savannas. In North America, subtropical species dominated with cashews and lychee trees present, and temperate trees such as roses, beeches, the legumes spread, while sedges, bulrushes, and ferns continued their ascent. Even more open landscapes allowed animals to grow to larger sizes than they had earlier in the Paleocene epoch 30 million years earlier, marine faunas became fairly modern, as did terrestrial vertebrate fauna on the northern continents
Oligocene
–
Restoration of Oligocene fauna of North America
11.
Geologic timescale
–
The table of geologic time spans, presented here, agrees with the nomenclature, dates and standard color codes set forth by the International Commission on Stratigraphy. Evidence from radiometric dating indicates that Earth is about 4.54 billion years old, the geology or deep time of Earth’s past has been organized into various units according to events which took place in each period. Older time spans, which predate the reliable record, are defined by their absolute age. Some other planets and moons within the Solar System have sufficiently rigid structures to have preserved records of their own histories, for example, Venus, Mars, dominantly fluid planets, such as the gas giants, do not preserve their history in a comparable manner. Apart from the Late Heavy Bombardment, events on other planets probably had little influence on the Earth. Construction of a scale that links the planets is, therefore, of only limited relevance to the Earths time scale. The existence, timing, and terrestrial effects of the Late Heavy Bombardment is still debated, the largest defined unit of time is the supereon, composed of eons. Eons are divided into eras, which are in turn divided into periods, epochs, the terms eonothem, erathem, system, series, and stage are used to refer to the layers of rock that correspond to these periods of geologic time in Earths history. Geologists qualify these units as early, mid, and late when referring to time, and lower, middle, for example, the lower Jurassic Series in chronostratigraphy corresponds to the early Jurassic Epoch in geochronology. The adjectives are capitalized when the subdivision is formally recognized, and lower case when not, thus early Miocene but Early Jurassic. Geologic units from the time but different parts of the world often look different and contain different fossils. For example, in North America the Lower Cambrian is called the Waucoban series that is subdivided into zones based on succession of trilobites. In East Asia and Siberia, the unit is split into Alexian, Atdabanian. A key aspect of the work of the International Commission on Stratigraphy is to reconcile this conflicting terminology, the term Anthropocene is used informally by popular culture and a growing number of scientists to describe the current epoch in which we are living. The term was coined by Paul Crutzen and Eugene Stoermer in 2000 to describe the current time, others say that humans have not even started to leave their biggest impact on Earth, and therefore the Anthropocene hasnt even started yet. Whatever the case, the ICS has not officially approved the term, leonardo da Vinci concurred with Aristotles interpretation that fossils represented the remains of ancient life. The 11th-century Persian geologist Avicenna and the 13th-century Dominican bishop Albertus Magnus extended Aristotles explanation into a theory of a petrifying fluid. Avicenna also first proposed one of the principles underlying geologic time scales, the Chinese naturalist Shen Kuo also recognized the concept of deep time
Geologic timescale
–
Key concepts
Geologic timescale
12.
Cenozoic
–
The Cenozoic Era is the current and most recent of the three Phanerozoic geological eras, following the Mesozoic Era and covering the period from 66 million years ago to the present day. The Cenozoic is also known as the Age of Mammals, because of the mammals that dominated, such as Entelodont, Paraceratherium. The extinction of many large groups such as non-avian dinosaurs, Plesiosauria and Pterosauria allowed the mammals and birds to greatly diversify. Early in the Cenozoic, following the K-Pg event, the planet was dominated by relatively small fauna, including mammals, birds, reptiles. From a geological perspective, it did not take long for mammals, some flightless birds grew larger than humans. These species are referred to as terror birds, and were formidable predators. Mammals came to occupy almost every available niche, and some also grew very large, the Earths climate had begun a drying and cooling trend, culminating in the glaciations of the Pleistocene Epoch, and partially offset by the Paleocene-Eocene Thermal Maximum. The continents also began looking roughly familiar at this time and moved into their current positions. The Cenozoic is divided into three periods, the Paleogene, Neogene, and Quaternary, and seven epochs, the Paleocene, Eocene, Oligocene, Miocene, Pliocene, Pleistocene, and Holocene. The common use of epochs during the Cenozoic helps paleontologists better organize, there is also more detailed knowledge of this era than any other because of the relatively young, well-preserved rocks associated with it. The Paleogene spans from the extinction of dinosaurs,66 million years ago. It features three epochs, the Paleocene, Eocene and Oligocene, the Paleocene ranged from 66 million to 56 million years ago. The Paleocene is a point between the devastation that is the K-T extinction, to the rich jungles environment that is the Early Eocene. The Early Paleocene saw the recovery of the earth, the continents began to take their modern shape, but all the continents and subcontinent India were separated from each other. Afro-Eurasia was separated by the Tethys Sea, and the Americas were separated by the strait of Panama and this epoch featured a general warming trend, with jungles eventually reaching the poles. The oceans were dominated by sharks as the large reptiles that had once ruled became extinct, archaic mammals filled the world such as creodonts and early primates that evolved during the Mesozoic, and as a result, there was nothing over 10 kilograms. The Eocene Epoch ranged from 56 million years to 33.9 million years ago, in the Early-Eocene, life was small and lived in cramped jungles, much like the Paleocene. There was nothing over the weight of 10 kilograms, among them were early primates, whales and horses along with many other early forms of mammals
Cenozoic
–
Basilosaurus
Cenozoic
–
Animals of the Miocene (
Chalicotherium,
Hyenadon,
Entelodont...). Mammals are the dominant terrestrial vertebrates of the Cenozoic.
Cenozoic
–
Megafauna of the Pleistocene (
mammoths,
cave lions,
woolly rhino,
Megaloceros, American
horses)
13.
Stratum
–
In geology and related fields, a stratum is a layer of sedimentary rock or soil with internally consistent characteristics that distinguish it from other layers. The stratum is the unit in a stratigraphic column and forms the basis of the study of stratigraphy. Each layer is one of a number of parallel layers that lie one upon another. They may extend over hundreds of thousands of kilometers of the Earths surface. Strata are typically seen as bands of different colored or differently structured material exposed in cliffs, road cuts, quarries, individual bands may vary in thickness from a few millimeters to a kilometer or more. Each band represents a mode of deposition, river silt, beach sand, coal swamp, sand dune, lava bed. Geologists study rock strata and categorize them by the material of beds, each distinct layer is typically assigned to the name of sheet, usually based on a town, river, mountain, or region where the formation is exposed and available for study. For example, the Burgess Shale is an exposure of dark, occasionally fossiliferous. Slight distinctions in material in a formation may be described as members, formations are collected into groups while groups may be collected into supergroups. Archaeological horizon Geologic formation Geologic map Geologic unit Law of superposition Bed GeoWhen Database
Stratum
–
Strata in
Salta (
Argentina).
Stratum
–
Goldenville strata in quarry in
Bedford,
Canada. These are
Middle Cambrian marine sediments. This formation covers over half of
Nova Scotia and is recorded as being 29,000 feet thick in some areas.
Stratum
Stratum
14.
Timeline of human evolution
–
The timeline of human evolution outlines the major events in the development of the human species, Homo sapiens, and the evolution of our ancestors. It includes brief explanations of some of the species, genera, and this timeline is based on studies from anthropology, paleontology, developmental biology, morphology, and from anatomical and genetic data. It does not address the origin of life, which discussion is provided by abiogenesis, a caution, Other than Mr Haeckels historic and emblematic tree, this article provides no phylogenetics analysis to help portray the complex, nonlinear facts of human evolution. One of several lines of descent, or taxonomic ranking
Timeline of human evolution
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Haeckel 's Paleontological Tree of Vertebrates (c. 1879). The evolutionary history of
species has been described as a "
tree " with many branches arising from a single trunk. While Haeckel's tree is somewhat outdated, it illustrates clearly the principles that more complex modern reconstructions can obscure.
Timeline of human evolution
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Pikaia
Timeline of human evolution
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A
Placoderm
Timeline of human evolution
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Panderichthys
15.
Ouranopithecus
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Based on O. macedoniensiss dental and facial anatomy, it has been suggested that the Ouranopithecus were actually dryopithecines. However, Ouranopithecines are probably closely related to the Ponginae. It is true that O. macedoniensis shares derived features with some early hominins and it has been suggested that it may be a synonym of Graecopithecus freybergi, although this is widely disputed in the literature. Media related to Ouranopithecus at Wikimedia Commons Human Timeline – Smithsonian, National Museum of Natural History
Ouranopithecus
–
Ouranopithecus Temporal range:
Miocene
16.
Sahelanthropus
–
Sahelanthropus tchadensis is an extinct homininae species that is dated to about 7 million years ago, during the Miocene epoch, possibly very close to the time of the chimpanzee–human divergence. Few specimens are known, other than the partial skull nicknamed Toumaï, existing fossils include a relatively small cranium named Toumaï, five pieces of jaw, and some teeth, making up a head that has a mixture of derived and primitive features. The braincase, being only 320 cm³ to 380 cm³ in volume, is similar to that of extant chimpanzees and is less than the approximate human volume of 1350 cm³. The teeth, brow ridges, and facial structure differ markedly from those found in Homo sapiens, cranial features show a flatter face, u-shaped dental arcade, small canines, an anterior foramen magnum, and heavy brow ridges. No postcranial remains have been recovered, the only known skull suffered a large amount of distortion during the time of fossilisation and discovery, as the cranium is dorsoventrally flattened, and the right side is depressed. Sahelanthropus tchadensis may have walked on two legs, upon examination of the foramen magnum in the primary study, the lead author speculated that a bipedal gait would not be unreasonable based on basicranial morphology similar to more recent hominins. Further, according to recent information, what might be a femur of a hominid was also discovered near the cranium—but which has not been published nor accounted for. All known material of Sahelanthropus was found between July 2001 and March 2002 at three sites, TM247, TM266, which yielded most of the material, including a cranium and a femur, and TM292. The discoverers claimed that S. tchadensis is the oldest known human ancestor after the split of the line from that of chimpanzees. The bones were found far from most previous hominin fossil finds, however, an Australopithecus bahrelghazali mandible was found in Chad by Mamelbaye Tomalta, Najia and Alain Beauvilain, Michel Brunet and Aladji H. E. With the sexual dimorphism known to have existed in early hominins, Sahelanthropus may represent a common ancestor of humans and chimpanzees, though no consensus has been reached yet by the scientific community. The original placement of species as a human ancestor but not a chimpanzee ancestor would complicate the picture of human phylogeny. Another possibility is that Toumaï is related to humans and chimpanzees, but is the ancestor of neither. Brigitte Senut and Martin Pickford, the discoverers of Orrorin tugenensis, even if this claim is upheld the find would lose none of its significance, because at present, very few chimpanzee or gorilla ancestors have been found anywhere in Africa. Thus if S. tchadensis is a relative of the chimpanzees or gorillas. And S. tchadensis does indicate that the last common ancestor of humans and chimpanzees is unlikely to closely resemble extant chimpanzees, indeed, some researchers consider suggestions that Sahelanthropus is too early to be a human ancestor to have evaporated. Sediment isotope analysis of atoms in the fossil yielded an age of about 7 million years. In fact, Toumaï may have been reburied in the recent past, taphonomic analysis reveals the likelihood of one, perhaps two, burial
Sahelanthropus
Sahelanthropus
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Detail of map.
Sahelanthropus
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Reconstruction of S. tchadensis by sculptor
Élisabeth Daynès
17.
Orrorin
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Orrorin tugenensis is a postulated early species of Homininae, estimated at 6.1 to 5.7 million years and discovered in 2000. It is not confirmed how Orrorin is related to modern humans and its discovery was an argument against the hypothesis that australopithecines are human ancestors, as much as it still remains the most prevalent hypothesis of human evolution as of 2012. The name of genus Orrorin means original man in Tugen, and the name of the only classified species, O. tugenensis, derives from Tugen Hills in Kenya, as of 2007,20 fossils of the species have been found. Orrorin had small teeth relative to its body size and its dentition differs from that found in Australopithecus in that its cheek teeth are smaller and less elongated mesiodistally and from Ardipithecus in that its enamel is thicker. The dentition differs from both species in the presence of a mesial groove on the upper canines. The canines are ape-like but reduced, like those found in Miocene apes, Orrorin had small post-canines and was microdont, like modern humans, whereas robust australopithecines were megadont. In the femur, the head is spherical and rotated anteriorly, the neck is elongated and oval in section, while these suggest that Orrorin was bipedal, the rest of the postcranium indicates it climbed trees. After the fossils were found in 2000, they were held at the Kipsaraman village community museum, since then, according to the Community Museums of Kenya chairman Eustace Kitonga, the fossils are stored at a secret bank vault in Nairobi. The main similarity is that the Orrorin femur is morphologically closer to that of H. sapiens than is Lucys, there is, however, some debate over this point. Other fossils found in the Lukeino Formation show that Orrorin lived in a dry evergreen forest environment, the team that found these fossils in 2000 was led by Brigitte Senut and Martin Pickford from the Muséum national dhistoire naturelle. This date is markedly different from those using the molecular clock approach. Life timeline List of human evolution fossils Martin Pickford Orrorin tugenensis - The Smithsonian Institutions Human Origins Program Human Timeline – Smithsonian, National Museum of Natural History
Orrorin
18.
Ardipithecus
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Ardipithecus is a genus of an extinct hominine that lived during Late Miocene and Early Pliocene in Afar Depression, Ethiopia. Two fossil species are described in the literature, A. ramidus, which lived about 4.4 million years ago during the early Pliocene, behavioral analysis showed that Ardipithecus could be very similar to chimpanzees, indicating that the early human ancestors were very chimpanzee-like in behaviour. A. ramidus was named in September 1994, the first fossil found was dated to 4.4 million years ago on the basis of its stratigraphic position between two volcanic strata, the basal Gaala Tuff Complex and the Daam Aatu Basaltic Tuff. The name Ardipithecus ramidus stems mostly from the Afar language, in which Ardi means ground/floor, the pithecus portion of the name is from the Greek word for ape. Like most hominids, but unlike all previously recognized hominins, it had a grasping hallux or big toe adapted for locomotion in the trees and it is not confirmed how much other features of its skeleton reflect adaptation to bipedalism on the ground as well. Like later hominins, Ardipithecus had reduced canine teeth, more fragments were recovered in 1994, amounting to 45% of the total skeleton. This fossil was described as a species of Australopithecus, but White. Between 1999 and 2003, a team led by Sileshi Semaw discovered bones. The fossils were dated to between 4.35 and 4.45 million years old, Ardipithecus ramidus had a small brain, measuring between 300 and 350 cm3. Like common chimpanzees, A. ramidus was much more prognathic than modern humans, the size of the upper canine tooth in A. ramidus males was not distinctly different from that of females. The features of the canine in A. ramidus contrast with the sexual dimorphism observed in common chimpanzees. The less pronounced nature of the canine teeth in A. ramidus has been used to infer aspects of the social behavior of the species. In particular, it has used to suggest that the last common ancestor of hominids. This is markedly different from social patterns in common chimpanzees, among which intermale, researchers in a 2009 study said that this condition compromises the living chimpanzee as a behavioral model for the ancestral hominid condition. A. ramidus existed more recently than the most recent common ancestor of humans and chimpanzees, nevertheless, it is in some ways unlike chimpanzees, suggesting that the common ancestor differs from the modern chimpanzee. After the chimpanzee and human lineages diverged, both underwent substantial evolutionary change, chimp feet are specialized for grasping trees, A. ramidus feet are better suited for walking. The canine teeth of A. ramidus are smaller, and equal in size between males and females, which suggests reduced male-to-male conflict, increased pair-bonding, and increased parental investment. Thus, fundamental reproductive and social behavioral changes probably occurred in long before they had enlarged brains and began to use stone tools
Ardipithecus
Ardipithecus
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Casts of Ardi's finger bones.
Ardipithecus
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Ardipithecus kadabba fossils.
19.
Australopithecus
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Australopithecus is an extinct genus of hominins. During that time, a number of australopithecine species emerged, including Australopithecus afarensis, A. africanus, A. anamensis, A. bahrelghazali, A. deyiremeda, A. garhi, and A. sediba. For some hominid species of time, such as A. robustus and A. boisei. If so, they would be considered robust australopiths, while the others would be gracile australopiths, however, if these species do constitute their own genus, they may be given their own name, Paranthropus. Australopithecus species played a significant part in human evolution, the genus Homo being derived from Australopithecus at some time after three years ago. Among other things, they were the first hominids to show the presence of a gene that causes increased length and ability of neurons in the brain, the duplicated SRGAP2 gene. One of the species eventually became the Homo genus in Africa around two million years ago, and eventually modern humans, H. sapiens sapiens. Gracile australopiths shared several traits with modern apes and humans, and were widespread throughout Eastern and Northern Africa around 3.5 million years ago, the earliest evidence of fundamentally bipedal hominids can be observed at the site of Laetoli in Tanzania. This site contains hominid footprints that are similar to those of modern humans and have been dated to as old as 3.6 million years. The footprints have generally classified as australopith because that is the only form of prehuman known to have existed in that region at that time. Australopithecus anamensis, A. afarensis, and A. africanus are among the most famous of the extinct hominins, a. africanus was once considered to be ancestral to the genus Homo. However, fossils assigned to the genus Homo have been found that are older than A. africanus, thus, the genus Homo either split off from the genus Australopithecus at an earlier date, or both developed from a yet possibly unknown common ancestor independently. According to the Chimpanzee Genome Project, the human and chimpanzee lineages diverged from a common ancestor about five to six years ago. Sahelanthropus tchadensis, commonly called Toumai, is seven million years old. One theory suggests that the human and chimpanzee lineages diverged somewhat at first, the brains of most species of Australopithecus were roughly 35% of the size of a modern human brain. Most species of Australopithecus were diminutive and gracile, usually standing 1.2 to 1.4 m tall, in several variations is a considerable degree of sexual dimorphism, males being larger than females. According to one scholar, A. Furthermore, thermoregulatory models suggest that Australopithecus species were fully covered, more like chimpanzees and bonobos. Modern humans do not appear to display the same degree of sexual dimorphism as Australopithecus did, in modern populations, males are on average a mere 15% larger than females, while in Australopithecus, males could be up to 50% larger than females
Australopithecus
Australopithecus
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A reconstruction of Australopithecus afarensis
Australopithecus
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The spot where the first Australopithecus boisei was discovered in Tanzania
Australopithecus
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Original skull of
Mrs. Ples, a female A. africanus
20.
Homo habilis
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Homo habilis is a species of the tribe Hominini, during the Gelasian and early Calabrian stages of the Pleistocene period, which lived between roughly 2.1 and 1.5 million years ago. LD 350-1 is a fossil jawbone fragment discovered in 2013 which has dated to 2.8 million years ago. There has been debate regarding its placement in the genus Homo rather than the genus Australopithecus. The small size and rather primitive attributes have led experts to propose excluding H. habilis from the genus Homo. These were later classified as milk teeth, and therefore considered difficult to link to taxa unlike permanent teeth, however, in 1959, Mary Leakey recovered the cranium of a young adult which had a small brain, large face, tiny canines and massive chewing teeth. H. habilis was short and had long arms compared to modern humans, however. H. habilis had a capacity slightly less than half of the size of modern humans. Despite the ape-like morphology of the bodies, H. habilis remains are accompanied by primitive stone tools. Homo habilis has often thought to be the ancestor of the more gracile and sophisticated Homo ergaster. New findings in 2007 seemed to confirm the view that H. habilis and H. erectus coexisted, an alternative explanation would be that any ancestral relationship from H. habilis to H. erectus would have to have been cladogenetic rather than anagenetic. Its brain size has been shown to range from 550 cm3 to 687 cm3, a virtual reconstruction published in 2015 estimated the endocranial volume at between 729 and 824 ml, larger than any previously published value. H. habilis brain capacity of around 640 cm³ was on average 50% larger than australopithecines and these hominins were smaller than modern humans, on average standing no more than 1.3 m tall. A fragment of fossilized jawbone, dated to around 2.8 million years ago, was discovered in the Ledi-Geraru research area in Afar Regional State in 2013. The fossil is considered the earliest evidence of the Homo genus known to date, the individual in question lived just after a major climate shift in the region, when forests and waterways were rapidly replaced by arid savannah. One set of remains, discovered by Donald Johanson and Tim White in Olduvai Gorge in 1986, included the important upper and lower limbs, specifically the humerus. Their finding stimulated some debate at the time, locomotor affinities of OH62 have been assessed primarily on the basis of its forelimb to hind limb proportions, which are known to be associated with locomotor behavior among living primates. Initial analyses concentrated on comparisons to the Australopithecus afarensis A. L. 288-1, in most dimensions—measured or estimated—the OH62 upper limb remains equaled or exceeded those of A. L. 288-1, while its lower limb remains appeared to be smaller. In this sense, it was more ‘‘primitive than A. L. 288-1, KNM ER1813 is a relatively complete cranium which dates to 1.9 million years old, discovered at Koobi Fora, Kenya by Kamoya Kimeu in 1973
Homo habilis
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Skull of Homo Habilis,
Indian Museum -
Paranthropus boisei to right
Homo habilis
Homo habilis
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KNM ER 1813.
Homo habilis
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Reconstruction of Homo habilis at the Westfälisches Museum für Archäologie, Herne
21.
Homo erectus
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Homo erectus is an extinct species of hominid that lived throughout most of the Pleistocene geological epoch. Its earliest fossil evidence dates to 1.9 million years ago and extends to 70,000 years ago, or, possibly, as recently as 35,000 years ago. It is generally thought that H. erectus originated in Africa and spread from there, migrating throughout Eurasia as far as Georgia, India, Sri Lanka, China, a new debate appeared in 2013, with the documentation of the Dmanisi skulls.58 million years ago. From there it migrated, in part, by 2, the fossil record shows that its development from about 1.8 mya to one mya was widely distributed, in Africa, the Transcaucasus, Indonesia, and in Vietnam, China, and India. The second hypothesis is that H. erectus evolved in Eurasia and they occupied the Dmanisi site from 1.85 million to 1.77 million years ago, which was about the same time or slightly before their earliest evidence in Africa. There are several proposed explanations of the dispersal of H. erectus georgicus—including whether or not Africa is the source), the Dutch anatomist Eugène Dubois was fascinated by Darwins theory of evolution especially as it applied to humankind. In 1886, he set out for Asia—which then was the region accepted as the cradle of evolution despite Darwins theory of African origin. In 1891, his team discovered a human fossil on the island of Java, the Java fossil from Indonesia aroused much public interest. It was dubbed by the press as Java Man, but few scientists accepted Dubois argument that his fossil was the transitional form—the so-called missing link—between apes. Java Man is now classified as Homo erectus, most of the spectacular discoveries of H. erectus next took place at the Zhoukoudian Project, now known as the Peking Man Site, in Zhoukoudian, China. This site was first discovered by Johan Gunnar Andersson in 1921 and was first excavated in 1921, canadian anatomist Davidson Blacks initial description of a lower molar as belonging to a previously unknown species prompted widely publicized interest. Extensive excavations followed, which altogether uncovered 200 human fossils from more than 40 individuals including five nearly complete skullcaps, german anatomist Franz Weidenreich provided much of the detailed description of this material in several monographs published in the journal Palaeontologica Sinica. Throughout much of the 20th century, anthropologists debated the role of H. erectus in human evolution, early in the century, due in part to the discoveries at Java and Zhoukoudian, it was widely accepted that modern humans first evolved in Asia. From the 1950s forward, numerous finds in East Africa confirmed the hypothesis of an African genesis and it is now generally accepted that H. erectus descended from either, 1) the earliest hominin genera, or 2) the earliest Homo-species. East Africa provided sympatric coexistence for H. erectus and H, in the 1950s, archaeologists John T. Robinson and Robert Broom named Telanthropus capensis, Robinson had discovered a jaw fragment in 1949 in Swartkrans, South Africa. Later, Simonetta proposed to re-designate it to Homo erectus, in 1961, Yves Coppens discovered a skull of Tchadanthropus uxoris, then the earliest fossil human discovered in north Africa. It was reported that the fossil had been so eroded by sand that it mimicked the appearance of an australopith. Although at first considered to be a specimen of H. habilis, T. uxoris is no longer considered a valid taxon, and has been subsumed into H. erectus
Homo erectus
Homo erectus
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Homo erectus,
University of Michigan Museum of Natural History, Ann Arbor, Michigan
Homo erectus
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Skull of Homo erectus,
Indian Museum
Homo erectus
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Dmanisi skull 3, Fossils skull
D2700 and D2735 jaw, two of several found in
Dmanisi in the
Georgian Caucasus.
22.
Neanderthal
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Neanderthals, or more rarely Neandertals, were a species or subspecies of archaic humans in the genus Homo that went extinct about 40,000 years ago. Neanderthals and modern humans share 99. 7% of their DNA and are closely related. Neanderthals left bones and stone tools in Eurasia, from Western Europe to Central, from the 1950s to the early 1980s, however, Neanderthals were widely considered a subspecies of Homo sapiens and a minority of scholars still hold this view. Several cultural assemblages have been linked to the Neanderthals in Europe, the earliest, the Mousterian stone tool culture, dates to about 160,000 years ago. Late Mousterian artifacts were found in Gorhams Cave on the south-facing coast of Gibraltar, male Neanderthals had cranial capacities averaging 1600 cm3, females 1300 cm3, extending to 1736 cm3 in Amud 1. This is notably larger than the 1250–1400 cm3 typical of modern humans, males stood 164–168 cm and females 152–156 cm tall. Recent studies also show that a few Neanderthals began mating with ancestors of modern humans long before the out of Africa migration of present day non-Africans. Claims that Neanderthals deliberately buried their dead, and if they did, the debate on deliberate Neanderthal burials has been active since the 1908 discovery of the well-preserved Chapelle-aux-Saints 1 skeleton in a small hole in a cave in southwestern France. In 2013, scientists sequenced the genome of a Neanderthal for the first time. The genome was extracted from the bone of a 50. In 2016, elaborate constructions of rings of broken stalagmites made by early Neanderthals around 176,000 years ago were discovered 336 m inside Bruniquel Cave in southwestern France and this would have required a more advanced social structure than previously known for Neanderthals. Thal is a spelling of the German word Tal, which means valley. Nevertheless, Kings name had priority over the proposal put forward in 1866 by Ernst Haeckel, the practice of referring to the Neanderthals and a Neanderthal emerged in the popular literature of the 1920s. The German pronunciation of Neanderthaler or Neandertaler is in the International Phonetic Alphabet, in British English, Neanderthal is pronounced with the /t/ as in German, but different vowels. In laymans American English, Neanderthal is pronounced with a /θ/ and /ɔ/ instead of the longer British /aː/, during the early 20th century the prevailing view was heavily influenced by Arthur Keith and Marcellin Boule, who wrote the first scientific description of a nearly complete Neanderthal skeleton. During the 1930s scholars Ernst Mayr, George Gaylord Simpson and Theodosius Dobzhansky reinterpreted the existing fossil record, Neanderthal man was classified as Homo sapiens neanderthalensis - an early subspecies contrasted with what was now called Homo sapiens sapiens. The obviously unbroken succession of fossil sites of both subspecies in Europe was considered evidence that there was a slow and gradual evolutionary transition from Neanderthals to modern humans, contextual interpretations of similar excavation sites in Asia lead to the hypothesis of multiregional origin of modern man in the 1980s. Current scientific ideas hold that both evolved from a common African ancestor, Homo erectus
Neanderthal
Neanderthal
Neanderthal
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The site of
Kleine Feldhofer Grotte where the type specimen was unearthed by miners in the 19th century
Neanderthal
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Skull, found in 1886 in
Spy, Belgium
23.
Anatomically modern human
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Anatomically modern humans evolved from archaic humans in the Middle Paleolithic, about 200,000 years ago. The emergence of modern human marks the dawn of the species Homo sapiens. Other fossils include the proposed Homo sapiens idaltu from Herto in Ethiopia that are almost 160,000 years old and the Skhul hominids from Israel, which are 90,000 years old. The oldest human remains from which an entire genome has been extracted belongs to Ust-Ishim man, however, it can and has been argued that Homo sapiens have been fully capable of modern behavior from the time they first evolved. The binomial name for the species of the human population is Homo sapiens. The species is taken to have emerged from a predecessor within the Homo genus around 200,000 years ago. Generally, modern humans are more lightly built than archaic humans from which they have evolved, Humans are a highly variable species, modern humans can show remarkably robust traits, and early modern humans even more so. Despite this, modern humans differ from archaic people in a range of anatomical details, the cranium lacks a pronounced occipital bun in the neck, a bulge that anchored considerable neck muscles in Neanderthals. Modern humans, even the ones, generally have a larger fore-brain than the archaic people. This will usually give a higher forehead, and reduced brow ridge and this splits the ridge into a central part and two distal parts. In current humans, often only the section of the ridge is preserved. This contrasts with archaic humans, where the ridge is pronounced. Modern humans commonly have a steep, even vertical forehead whereas their predecessors had foreheads that sloped strongly backwards, according to Desmond Morris, the vertical forehead in humans not only houses larger brains, but plays an important role in human communication through eyebrow movements and forehead skin wrinkling. Compared to archaic people, anatomically modern humans have smaller, differently shaped teeth and this results in a smaller, more receded dentary, making the rest of the jaw-line stand out, giving an often quite prominent chin. The central part of the forming the chin carries a triangularly shaped area forming the apex of the chin called the mental trigon. Particularly in living population, the use of fire and tools require fewer jaw muscles, giving slender, compared to archaic people, modern humans have smaller, lower faces. The body skeletons of even the earliest and most robustly built modern humans were less robust than those of Neanderthals, particularly regarding the long bones of the limbs, the distal bones are nearly the same size or slightly shorter than the proximal bones. In ancient people, particularly Neanderthals, the bones were shorter
Anatomically modern human
–
Homo sapiens sapiens
Anatomically modern human
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Anatomical comparison of skulls of
Homo sapiens (left) and
Homo neanderthalensis (right) (in
Cleveland Museum of Natural History) Features compared are the
braincase shape,
forehead,
browridge,
nasal bone,
projection,
cheek bone angulation,
chin, and
occipital contour.
Anatomically modern human
–
Homo erectus
Anatomically modern human
–
Homo ergaster
24.
Stone Age
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The Stone Age was a broad prehistoric period during which stone was widely used to make implements with an edge, a point, or a percussion surface. The period lasted roughly 3.4 million years, and ended between 8700 BCE and 2000 BCE with the advent of metalworking, bone tools were used during this period as well but are rarely preserved in the archaeological record. The Stone Age is further subdivided by the types of tools in use. According to the age and location of the current evidence, the cradle of the genus is the East African Rift System, especially toward the north in Ethiopia, where it is bordered by grasslands. The closest relative among the living primates, the genus Pan, represents a branch that continued on in the deep forest. The rift served as a conduit for movement into southern Africa and also north down the Nile into North Africa and through the continuation of the rift in the Levant to the vast grasslands of Asia. The oldest indirect evidence found of stone tool use is fossilised animal bones with tool marks, the oldest stone tools were excavated from the site of Lomekwi 3 in West Turkana, northwestern Kenya, and date to 3.3 million years old. Prior to the discovery of these Lomekwian tools, the oldest known stone tools had been found at sites at Gona, Ethiopia, on the sediments of the paleo-Awash River. All the tools come from the Busidama Formation, which lies above a disconformity, or missing layer, the oldest sites containing tools are dated to 2. 6–2.55 mya. One of the most striking circumstances about these sites is that they are from the Late Pliocene, excavators at the locality point out that. the earliest stone tool makers were skilled flintknappers. The possible reasons behind this seeming abrupt transition from the absence of tools to the presence thereof include. The species who made the Pliocene tools remains unknown, fragments of Australopithecus garhi, Australopithecus aethiopicus and Homo, possibly Homo habilis, have been found in sites near the age of the Gona tools. Innovation of the technique of smelting ore ended the Stone Age, the first most significant metal manufactured was bronze, an alloy of copper and tin, each of which was smelted separately. The Chalcolithic by convention is the period of the Bronze Age. The Bronze Age was followed by the Iron Age, the transition out of the Stone Age occurred between 6000 BCE and 2500 BCE for much of humanity living in North Africa and Eurasia. Note the Rudna Glava mine in Serbia, Ötzi the Iceman, a mummy from about 3300 BCE carried with him a copper axe and a flint knife. In regions such as Sub-Saharan Africa, the Stone Age was followed directly by the Iron Age, the Middle East and southeastern Asian regions progressed past Stone Age technology around 6000 BCE. Europe, and the rest of Asia became post–Stone Age societies by about 4000 BCE, the proto-Inca cultures of South America continued at a Stone Age level until around 2000 BCE, when gold, copper and silver made their entrance
Stone Age
–
Obsidian projectile point
Stone Age
–
Modern
Awash River, Ethiopia, descendant of the Palaeo-Awash, source of the sediments in which the oldest Stone Age tools have been found
Stone Age
–
A variety of
stone tools
Stone Age
–
This is a Mode 1, or Oldowan,
stone tool from the western Sahara.
25.
Control of fire by early humans
–
The control of fire by early humans was a turning point in the cultural aspect of human evolution. Fire provided a source of warmth, protection, and a method for cooking food and these cultural advancements allowed for human geographic dispersal, cultural innovations, and changes to diet and behavior. Additionally, creating fire allowed the expansion of activity to proceed into the dark. Claims for the earliest definitive evidence of control of fire by a member of Homo range from 0.2 to 1.7 million years ago, evidence for the controlled use of fire by Homo erectus, beginning some 600,000 years ago, has wide scholarly support. Evidence of widespread control of fire by anatomically modern humans dates to approximately 125,000 years ago, most of the evidence of controlled use of fire during the Lower Paleolithic is uncertain and has limited scholarly support. The inconclusiveness of some of the lies behind the fact that there exist other plausible explanations, such as natural processes. Recent findings strongly support that the earliest known controlled use of fire took place in Wonderwerk Cave, over time, early humans figured out how to create fire. Archaeological evidence, suggests that happened between 700,000 years ago and 120,000 years ago. Findings from the Wonderwerk Cave site, in the Northern Cape province of South Africa, east African sites, such as Chesowanja near Lake Baringo, Koobi Fora, and Olorgesailie in Kenya, show some possible evidence that fire was controlled by early humans. In Chesowanja archaeologists found red clay clasts dated to be from 1.4 Mya and these clasts must have been heated to 400 °C to harden. However, deliberate use of fire in Chesowanja is still debatable because there are reasons to believe that the burning of clay might have happened by chance. In Koobi Fora, sites FxJjzoE and FxJj50 show evidence of control of fire by Homo erectus at 1.5 Mya with findings of reddened sediment that could come from heating at 200–400 °C. A hearth-like depression that could have used to burn bones was found at a site in Olorgesailie. However, it did not contain any charcoal and no signs of fire have been observed, some microscopic charcoal was found, but it could have resulted from a natural brush fire. In Gadeb, Ethiopia, fragments of welded tuff that appeared to have been burned were found in Locality 8E, in the Middle Awash River Valley, cone-shaped depressions of reddish clay were found that could have been formed by temperatures of 200 °C. These features are thought to be burned tree stumps such that the early hominids could have fire away from their habitation site, burned stones are also found in Awash Valley, but volcanic welded tuff is also found in the area which could explain the burned stones. In Xihoudu in Shanxi Province, China, the black, blue, in 1985, a parallel site in China, Yuanmou in the Yunnan Province, archaeologists found blackened mammal bones which date back to 1.7 Mya BP. A site at Bnot Yaakov Bridge, Israel, has claimed to show that H. erectus or H. ergaster controlled fires between 790,000 and 690,000 BP
Control of fire by early humans
–
A reconstruction of
Homo erectus, the earliest human species that is known to have controlled fire (reconstruction shown in Westfälisches Landesmuseum, Herne, Germany, in a 2006 exhibition)
Control of fire by early humans
–
Zhoukoudian Caves, a
World Heritage Site and an early site of human use of fire in
China
26.
Homo antecessor
–
Homo antecessor is an extinct human species dating from 1.2 million to 800,000 years ago, that was discovered by Eudald Carbonell, Juan Luis Arsuaga and J. M. Bermúdez de Castro. The unique mix of modern and primitive traits led the researchers to deem the fossils a new species, H. antecessor, in 1997. Regarding its great age the species must be related to Out of Africa I, author Richard Klein argues that it was a separate species that evolved from H. ergaster. Some scientists consider H. antecessor to be the species as H. heidelbergensis. It’s possible that H. antecessor adults didn’t really look much like H. sapiens at all, the best-preserved fossil is a maxilla that belonged to a ten-year-old individual found in Spain. Based on palaeomagnetic measurements, it is thought to be older than 857–780 ka, in 1994 and 1995,80 fossils of six individuals who may have belonged to the species were found in Atapuerca, Spain. At the site were numerous examples of cuts where the flesh had been flensed from the bones, footprints presumed to be from H. antecessor dating to more than 800,000 years ago have been found at Happisburgh on the coast of Norfolk, England. A2013 DNA analysis from a 400, 000-year-old femur from Spains Sima de los Huesos in the Atapuerca Mountains – the oldest hominin sequence yet published – did not help to overcome contradictions. Results left researchers baffled as the sequence suggests link to mystery population of the Denisovans instead of the Neanderthals as was anticipated. According to the Science X Network the excavation team at the site of Gran Dolina has succeeded to provide conclusive dating of the strata where the Homo antecessor fossils were found. A2014 publication in the Journal of Archaeological Science states that the sediment of Gran Dolina is 900,000 years old, a speciation event could have occurred in Africa/Western Eurasia, originating a new Homo clade, and further, Homo antecessor. Could be a branch of this clade placed at the westernmost region of the Eurasian continent. H. antecessor was about 1. 6–1.8 m tall and their brain sizes were roughly 1, 000–1,150 cm³, smaller than the 1,350 cm³ average of modern humans. Due to fossil scarcity, very little more is known about the physiology of H. antecessor, yet it was likely to have been more robust than H. heidelbergensis. According to Juan Luis Arsuaga, one of the co-directors of the excavation in Burgos, H. antecessor might have been right-handed and this hypothesis is based on tomography techniques. Arsuaga also claims that the range of audition is similar to H. sapiens. Arsuagas team is currently pursuing a DNA map of H. antecessor, based on teeth eruption pattern, the researchers think that H. antecessor had the same development stages as H. sapiens, though probably at a faster pace. Other significant features demonstrated by the species are a protruding occipital bun, a low forehead, some of the remains are almost indistinguishable from the fossil attributable to the 1.5 million year old Turkana Boy, belonging to H. ergaster
Homo antecessor
Homo antecessor
–
Model of a female Homo antecessor of
Atapuerca practicing cannibalism (Ibeas Museum, Burgos, Spain).
Homo antecessor
–
Model of a male Homo antecessor of Atapuerca mountains (Ibeas Museum, Burgos, Spain)
27.
Cooking
–
Cooking or cookery is the art, technology and craft of preparing food for consumption with the use of heat. The ways or types of cooking also depend on the skill, cooking is done both by people in their own dwellings and by professional cooks and chefs in restaurants and other food establishments. Cooking can also occur through chemical reactions without the presence of heat, such as in ceviche, preparing food with heat or fire is an activity unique to humans. It may have started around 2 million years ago, though evidence for it reaches no more than 1 million years ago. The expansion of agriculture, commerce, trade and transportation between civilizations in different regions offered cooks many new ingredients, New inventions and technologies, such as the invention of pottery for holding and boiling water, expanded cooking techniques. Some modern cooks apply advanced scientific techniques to food preparation to further enhance the flavor of the dish served, phylogenetic analysis suggests that human ancestors may have invented cooking as far back as 1.8 million to 2.3 million years ago. Re-analysis of burnt bone fragments and plant ashes from the Wonderwerk Cave, there is evidence that Homo erectus was cooking their food as early as 500,000 years ago. Evidence for the use of fire by Homo erectus beginning some 400,000 years ago has wide scholarly support. Archeological evidence, from 300,000 years ago, in the form of ancient hearths, earth ovens, burnt animal bones, and flint, are found across Europe, anthropologists think that widespread cooking fires began about 250,000 years ago, when hearths started appearing. More recently, the earliest hearths have been reported to be at least 790,000 years old, in the seventeenth and eighteenth centuries, food was a classic marker of identity in Europe. In the nineteenth-century Age of Nationalism cuisine became a symbol of national identity. Communication between the Old World and the New World in the Colombian exchange influenced the history of cooking, the Industrial Revolution brought mass-production, mass-marketing and standardization of food. Factories processed, preserved, canned, and packaged a wide variety of foods, in the 1920s, freezing methods, cafeterias and fast-food establishments emerged. Along with changes in food, starting early in the 20th century, governments have issued nutrition guidelines, the 1916 Food For Young Children became the first USDA guide to give specific dietary guidelines. Updated in the 1920s, these guides gave shopping suggestions for different-sized families along with a Depression Era revision which included four cost levels, in 1943, the USDA created the Basic Seven chart to make sure that people got the recommended nutrients. It included the first-ever Recommended Daily Allowances from the National Academy of Sciences, in 1956, the Essentials of an Adequate Diet brought recommendations which cut the number of groups that American school children would learn about down to four. In 1979, a guide called Food addressed the link between too much of certain foods and chronic diseases, but added fats, oils, most ingredients in cooking are derived from living organisms. Vegetables, fruits, grains and nuts as well as herbs and spices come from plants, while meat, eggs, mushrooms and the yeast used in baking are kinds of fungi
Cooking
–
A chef preparing steak
Cooking
–
Historical oven cooking depicted in a painting by
Jean-François Millet
Cooking
–
Doughnuts frying in oil
Cooking
–
Water is often used to cook foods such as
noodles.
28.
Clothing
–
Clothing is fiber and textile material worn on the body. The wearing of clothing is mostly restricted to human beings and is a feature of all human societies. The amount and type of clothing worn depends on type, social. Some clothing types can be gender-specific, physically, clothing serves many purposes, it can serve as protection from the elements, and can enhance safety during hazardous activities such as hiking and cooking. It protects the wearer from rough surfaces, rash-causing plants, insect bites, splinters, thorns, Clothes can insulate against cold or hot conditions. Further, they can provide a barrier, keeping infectious. Clothing also provides protection from ultraviolet radiation, there is no easy way to determine when clothing was first developed, but some information has been inferred by studying lice. The body louse specifically lives in clothing, and diverge from head lice about 170 millennia ago, another theory is that modern humans are the only survivors of several species of primates who may have worn clothes and that clothing may have been used as long ago as 650 millennia. Other louse-based estimates put the introduction of clothing at around 42, the most obvious function of clothing is to improve the comfort of the wearer, by protecting the wearer from the elements. In hot climates, clothing provides protection from sunburn or wind damage, shelter usually reduces the functional need for clothing. For example, coats, hats, gloves, and other layers are normally removed when entering a warm home. Similarly, clothing has seasonal and regional aspects, so that thinner materials, Clothing performs a range of social and cultural functions, such as individual, occupational and gender differentiation, and social status. In many societies, norms about clothing reflect standards of modesty, religion, gender, Clothing may also function as a form of adornment and an expression of personal taste or style. Clothing can and has in history been made from a wide variety of materials. Materials have ranged from leather and furs, to materials, to elaborate and exotic natural. Not all body coverings are regarded as clothing, Clothing protects against many things that might injure the uncovered human body. Clothes protect people from the elements, including rain, snow, wind, however, clothing that is too sheer, thin, small, tight, etc. offers less protection. Clothes also reduce risk during activities such as work or sport, some clothing protects from specific environmental hazards, such as insects, noxious chemicals, weather, weapons, and contact with abrasive substances
Clothing
–
Clothing in history, showing (from top) Egyptians, Ancient Greeks, Romans, Byzantines, Franks, and 13th through 15th century Europeans.
Clothing
–
A
baby wearing many items of
winter clothing:
headband,
cap, fur-lined
coat,
shawl and
sweater
Clothing
–
Former 3rd Duke of Fife wearing a traditional
Scottish kilt. (1984)
Clothing
–
Former
US Secretary of State Condoleezza Rice and
Turkish President Abdullah Gül both wearing Western-style
business suits.
29.
Origin of speech
–
The origin of speech in Homo sapiens is a widely debated and controversial topic. The problems relate to humans unprecedented use of the tongue, lips, other animals vocalise, but do not use the tongue to modulate sounds. The topic is a separate one because language is not necessarily spoken, Speech is in this sense optional, although it is the default modality for language. Uncontroversially, monkeys, apes and humans, like other animals, have evolved specialised mechanisms for producing sound for purposes of social communication. On the other hand, no monkey or ape uses its tongue for such purposes, the term modality means the chosen representational format for encoding and transmitting information. A striking feature of language is that it is modality-independent, should an impaired child be prevented from hearing or producing sound, its innate capacity to master a language may equally find expression in signing. Sign languages of the deaf are independently invented and have all the properties of spoken language except for the modality of transmission. From this it appears that the centres of the human brain must have evolved to function optimally irrespective of the selected modality. Animal communication systems routinely combine visible with audible properties and effects, no vocally impaired whale, dolphin or songbird, for example, could express its song repertoire equally in visual display. Indeed, in the case of communication, message and modality are not capable of being disentangled. Whatever message is being conveyed stems from intrinsic properties of the signal, modality independence should not be confused with the ordinary phenomenon of multimodality. Monkeys and apes rely on a repertoire of species-specific gesture-calls — emotionally expressive vocalisations inseparable from the visual displays which accompany them, humans also have species-specific gesture-calls — laughs, cries, sobs and so forth — together with involuntary gestures accompanying speech. Many animal displays are polymodal in that appears designed to exploit multiple channels simultaneously. The human linguistic property of modality independence is conceptually distinct from this and it allows the speaker to encode the informational content of a message in a single channel, while switching between channels as necessary. Modern city-dwellers switch effortlessly between the word and writing in its various forms — handwriting, typing, e-mail. Whichever modality is chosen, it can transmit the full message content without external assistance of any kind. When talking on the telephone, for example, any accompanying facial or manual gestures, when typing or manually signing, conversely, theres no need to add sounds. Then, when released from the taboo, these same individuals resume narrating stories by the fireside or in the dark, speaking is the default modality for language in all cultures
Origin of speech
–
Human vocal tract
Origin of speech
–
Places of articulation (passive and active): 1. Exo-labial, 2. Endo-labial, 3. Dental, 4. Alveolar, 5. Post-alveolar, 6. Pre-palatal, 7. Palatal, 8. Velar, 9. Uvular, 10. Pharyngeal, 11. Glottal, 12. Epiglottal, 13. Radical, 14. Postero-dorsal, 15. Antero-dorsal, 16. Laminal, 17. Apical, 18. Sub-apical
Origin of speech
–
Linguistics
Origin of speech
–
Birds flocking, an example of
self-organization in biology
30.
Behavioral modernity
–
Behavioral modernity is a suite of behavioral and cognitive traits that distinguishes current Homo sapiens from other anatomically modern humans, hominins, and primates. Underlying these behaviors and technological innovations are cognitive and cultural foundations that have been documented experimentally and ethnographically, some of these human universal patterns are cumulative cultural adaptation, social norms, language, cooperative breeding, and extensive help and cooperation beyond close kin. Arising from differences in the record, a debate continues as to whether anatomically modern humans were behaviorally modern as well. There are many theories on the evolution of behavioral modernity and these generally fall into two camps, gradualist and cognitive approaches. The Later Upper Paleolithic Model refers to the idea that human behavior arose through cognitive, genetic changes abruptly around 40. Other models focus on how human behavior may have arisen through gradual steps. In order to classify what traits should be included in human behavior. Some examples of human universals are abstract thought, planning, trade, cooperative labor, body decoration, control. Along with these traits, humans possess a heavy reliance on social learning and this cumulative cultural change or cultural ratchet separates human culture from social learning in animals. As well, a reliance on social learning may be responsible in part for humans rapid adaptation to environments outside of Africa. Since cultural universals are found in all including some of the most isolated indigenous groups. Archaeologically a number of empirical traits have been used as indicators of human behavior. While these are often debated a few are generally agreed upon, shea outlines a variety of problems with this concept, arguing instead for behavioral variability, which, according to the author, better describes the archaeological record. Some researchers argue that a greater emphasis should be placed on identifying only those artifacts which are unquestionably, or purely and these authors note that traits used as a metric for behavioral modernity do not appear as a package until around 40–50,000 years ago. Klein specifically describes evidence of fishing, bone shaped as a tool, hearths, significant artifact diversity, although assemblages before 50,000 years ago show some diversity the only distinctly modern tool assemblages appear in Europe at 48,000. According to these authors, art only becomes common beyond this switching point, most researchers argue that a neurological or genetic change, perhaps one enabling complex language such as FOXP2, caused this revolutionary change in our species. Howiesons Poort, Blombos, and other South African archaeological sites, for example, show evidence of marine resource acquisition, trade, and abstract ornamentation at least by 80,000 years ago. Given evidence from Africa and the Middle East, a variety of hypotheses have put forth to describe an earlier
Behavioral modernity
–
Upper paleolithic, 16,000 years old, cave painting from
Lascaux cave in France
31.
Hominidae
–
Several revisions in classifying the great apes have caused the use of the term hominid to vary over time. Its original meaning referred only to humans and their closest non-extant relatives and that restrictive meaning has now been largely assumed by the term hominin, which comprises all members of the human clade after the split from the chimpanzees. The current, 21st-century meaning of hominid includes all the great apes including humans, the most recent common ancestor of all Hominidae lived roughly 14 million years ago, when the ancestors of the orangutans speciated from the ancestral line of the other three genera. Those ancestors of the family Hominidae had already speciated from the family Hylobatidae, in the early Miocene, about 22 million years ago, there were many species of arboreally adapted primitive catarrhines from East Africa, the variety suggests a long history of prior diversification. Fossils at 20 million years ago include fragments attributed to Victoriapithecus, the most recent of these far-flung Miocene apes is Oreopithecus, from the fossil-rich coal beds in northern Italy and dated to 9 million years ago. Species close to the last common ancestor of gorillas, chimpanzees and humans may be represented by Nakalipithecus fossils found in Kenya and Ouranopithecus found in Greece. Molecular evidence suggests that between 8 and 4 million years ago, first the gorillas, and then the split off from the line leading to the humans. Human DNA is approximately 98. 4% identical to that of chimpanzees when comparing single nucleotide polymorphisms, the earliest fossils argued by some to belong to the human lineage are Sahelanthropus tchadensis and Orrorin tugenensis, followed by Ardipithecus, with species Ar. kadabba and Ar. ramidus. The classification of the apes has been revised several times in the last few decades. The original meaning of the referred to only humans and their closest relatives—what is now the modern meaning of the term hominin. And the meaning of the taxon Hominidae changed gradually, leading to a different usage of hominid that today all the great apes including humans. A hominid is a member of the family Hominidae, the apes, orangutans, gorillas, chimpanzees. A hominine is a member of the subfamily Homininae, gorillas, chimpanzees, a hominin is a member of the tribe Hominini, Chimpanzees and humans. A homininan is a member of the subtribe Hominina of the tribe Hominini, a human is a member of the genus Homo, of which Homo sapiens is the only extant species, and within that Homo sapiens sapiens is the only surviving subspecies. For each clade it is indicated approximately when newer extant clades emerged, some texts will refer to Homonini as the Hominina branch. Many scientists, including paleoanthropologists, continue to use the term hominid to mean humans, as mentioned, Hominidae was originally the name given to the family of humans and their close relatives, with the other great apes all being placed in a separate family, the Pongidae. However, that eventually made Pongidae paraphyletic because at least one great ape species proved to be more closely related to humans than to other great apes. Most taxonomists today encourage monophyletic groups—this would require, in this case, thus, many biologists now assign Pongo to the family Hominidae
Hominidae
Hominidae
–
Sumatran orangutan (Pongo abelii)
Hominidae
–
A reconstruction of a female
Australopithecus afarensis (
National Museum of Natural History)
Hominidae
–
Humans are one of the four
extant hominid genera.
32.
Cartesian coordinate system
–
Each reference line is called a coordinate axis or just axis of the system, and the point where they meet is its origin, usually at ordered pair. The coordinates can also be defined as the positions of the projections of the point onto the two axis, expressed as signed distances from the origin. One can use the principle to specify the position of any point in three-dimensional space by three Cartesian coordinates, its signed distances to three mutually perpendicular planes. In general, n Cartesian coordinates specify the point in an n-dimensional Euclidean space for any dimension n and these coordinates are equal, up to sign, to distances from the point to n mutually perpendicular hyperplanes. The invention of Cartesian coordinates in the 17th century by René Descartes revolutionized mathematics by providing the first systematic link between Euclidean geometry and algebra. Using the Cartesian coordinate system, geometric shapes can be described by Cartesian equations, algebraic equations involving the coordinates of the points lying on the shape. For example, a circle of radius 2, centered at the origin of the plane, a familiar example is the concept of the graph of a function. Cartesian coordinates are also tools for most applied disciplines that deal with geometry, including astronomy, physics, engineering. They are the most common system used in computer graphics, computer-aided geometric design. Nicole Oresme, a French cleric and friend of the Dauphin of the 14th Century, used similar to Cartesian coordinates well before the time of Descartes. The adjective Cartesian refers to the French mathematician and philosopher René Descartes who published this idea in 1637 and it was independently discovered by Pierre de Fermat, who also worked in three dimensions, although Fermat did not publish the discovery. Both authors used a single axis in their treatments and have a length measured in reference to this axis. The concept of using a pair of axes was introduced later, after Descartes La Géométrie was translated into Latin in 1649 by Frans van Schooten and these commentators introduced several concepts while trying to clarify the ideas contained in Descartes work. Many other coordinate systems have developed since Descartes, such as the polar coordinates for the plane. The development of the Cartesian coordinate system would play a role in the development of the Calculus by Isaac Newton. The two-coordinate description of the plane was later generalized into the concept of vector spaces. Choosing a Cartesian coordinate system for a one-dimensional space – that is, for a straight line—involves choosing a point O of the line, a unit of length, and an orientation for the line. An orientation chooses which of the two half-lines determined by O is the positive, and which is negative, we say that the line is oriented from the negative half towards the positive half
Cartesian coordinate system
–
The
right hand rule.
Cartesian coordinate system
–
Illustration of a Cartesian coordinate plane. Four points are marked and labeled with their coordinates: (2,3) in green, (−3,1) in red, (−1.5,−2.5) in blue, and the origin (0,0) in purple.
Cartesian coordinate system
–
3D Cartesian Coordinate Handedness
33.
Geologic time scale
–
The table of geologic time spans, presented here, agrees with the nomenclature, dates and standard color codes set forth by the International Commission on Stratigraphy. Evidence from radiometric dating indicates that Earth is about 4.54 billion years old, the geology or deep time of Earth’s past has been organized into various units according to events which took place in each period. Older time spans, which predate the reliable record, are defined by their absolute age. Some other planets and moons within the Solar System have sufficiently rigid structures to have preserved records of their own histories, for example, Venus, Mars, dominantly fluid planets, such as the gas giants, do not preserve their history in a comparable manner. Apart from the Late Heavy Bombardment, events on other planets probably had little influence on the Earth. Construction of a scale that links the planets is, therefore, of only limited relevance to the Earths time scale. The existence, timing, and terrestrial effects of the Late Heavy Bombardment is still debated, the largest defined unit of time is the supereon, composed of eons. Eons are divided into eras, which are in turn divided into periods, epochs, the terms eonothem, erathem, system, series, and stage are used to refer to the layers of rock that correspond to these periods of geologic time in Earths history. Geologists qualify these units as early, mid, and late when referring to time, and lower, middle, for example, the lower Jurassic Series in chronostratigraphy corresponds to the early Jurassic Epoch in geochronology. The adjectives are capitalized when the subdivision is formally recognized, and lower case when not, thus early Miocene but Early Jurassic. Geologic units from the time but different parts of the world often look different and contain different fossils. For example, in North America the Lower Cambrian is called the Waucoban series that is subdivided into zones based on succession of trilobites. In East Asia and Siberia, the unit is split into Alexian, Atdabanian. A key aspect of the work of the International Commission on Stratigraphy is to reconcile this conflicting terminology, the term Anthropocene is used informally by popular culture and a growing number of scientists to describe the current epoch in which we are living. The term was coined by Paul Crutzen and Eugene Stoermer in 2000 to describe the current time, others say that humans have not even started to leave their biggest impact on Earth, and therefore the Anthropocene hasnt even started yet. Whatever the case, the ICS has not officially approved the term, leonardo da Vinci concurred with Aristotles interpretation that fossils represented the remains of ancient life. The 11th-century Persian geologist Avicenna and the 13th-century Dominican bishop Albertus Magnus extended Aristotles explanation into a theory of a petrifying fluid. Avicenna also first proposed one of the principles underlying geologic time scales, the Chinese naturalist Shen Kuo also recognized the concept of deep time
Geologic time scale
–
Key concepts
Geologic time scale
34.
Charles Lyell
–
Sir Charles Lyell, 1st Baronet, FRS was a British lawyer and the foremost geologist of his day. Principles of Geology also challenged theories popularized by Georges Cuvier, which were the most accepted and circulated ideas about geology in England at the time and he also coined the currently-used names for geological eras, Paleozoic, Mesozoic and Cenozoic. He incorrectly conjectured that icebergs may be the emphasis behind the transport of glacial erratics, Lyell was one of the first to believe that the world is older than 300 million years, on the basis of its geological anomalies. He was a friend of Charles Darwin, and contributed significantly to Darwins thinking on the processes involved in evolution. He helped to arrange the publication in 1858 of papers by Darwin and Alfred Russel Wallace on natural selection. He later published evidence from geology of the man had existed on Earth. Lyell was born 14 November 1797 in Scotland about 15 miles north of Dundee in Kinnordy and he was the eldest of ten children. Lyells father, also named Charles Lyell, was a lawyer and botanist of minor repute, the house/place of his birth is located in the north-west of the Central Lowlands in the valley of the Highland Boundary Fault. Round the house, in the valley, is farmland. His familys second home was in a different geological and ecological area, he spent much of his childhood at Bartley Lodge in the New Forest. Lyell entered Exeter College, Oxford, in 1816, and attended William Bucklands lectures and he graduated BA second class in classics, December 1819, and M. A.1821. After graduation he took up law as a profession, entering Lincolns Inn in 1820 and he completed a circuit through rural England, where he could observe geological phenomena. In 1821 he attended Robert Jamesons lectures in Edinburgh, and visited Gideon Mantell at Lewes, in 1823 he was elected joint secretary of the Geological Society. As his eyesight began to deteriorate, he turned to geology as a full-time profession and his first paper, On a recent formation of freshwater limestone in Forfarshire, was presented in 1822. In 1832, Lyell married Mary Horner in Bonn, daughter of Leonard Horner, the new couple spent their honeymoon in Switzerland and Italy on a geological tour of the area. During the 1840s, Lyell travelled to the United States and Canada, after the Great Chicago Fire, Lyell was one of the first to donate books to help found the Chicago Public Library. In 1866, he was elected a member of the Royal Swedish Academy of Sciences. Lyells wife died in 1873, and two years later Lyell himself died as he was revising the twelfth edition of Principles and he is buried in Westminster Abbey
Charles Lyell
–
Sir Charles Lyell, Bt
Charles Lyell
–
Charles Lyell at the
British Association meeting in Glasgow 1840. Painting by Alexander Craig.
Charles Lyell
–
Lyell between 1865 and 1870
Charles Lyell
–
The frontispiece from Elements of Geology
35.
Mollusc
–
The molluscs compose the large phylum Mollusca of invertebrate animals. Around 85,000 extant species of molluscs are recognized, molluscs are the largest marine phylum, comprising about 23% of all the named marine organisms. Numerous molluscs also live in freshwater and terrestrial habitats and they are highly diverse, not just in size and in anatomical structure, but also in behaviour and in habitat. The phylum is divided into 9 or 10 taxonomic classes. The gastropods are by far the most numerous molluscs in terms of classified species, the three most universal features defining modern molluscs are a mantle with a significant cavity used for breathing and excretion, the presence of a radula, and the structure of the nervous system. Other than these things, molluscs express great morphological diversity, so many textbooks base their descriptions on an ancestral mollusc. This has a single, limpet-like shell on top, which is made of proteins and chitin reinforced with calcium carbonate, the underside of the animal consists of a single muscular foot. Although molluscs are coelomates, the coelom tends to be small, the main body cavity is a hemocoel through which blood circulates, their circulatory systems are mainly open. The generalized mollusc has two paired nerve cords, or three in bivalves, the brain, in species that have one, encircles the esophagus. Most molluscs have eyes, and all have sensors to detect chemicals, vibrations, the simplest type of molluscan reproductive system relies on external fertilization, but more complex variations occur. All produce eggs, from which may emerge trochophore larvae, more complex veliger larvae, good evidence exists for the appearance of gastropods, cephalopods and bivalves in the Cambrian period 541 to 485.4 million years ago. Molluscs have, for centuries, also been the source of important luxury goods, notably pearls, mother of pearl, Tyrian purple dye and their shells have also been used as money in some preindustrial societies. Mollusc species can also represent hazards or pests for human activities, the bite of the blue-ringed octopus is often fatal, and that of Octopus apollyon causes inflammation that can last for over a month. Stings from a few species of large tropical cone shells can also kill, schistosomiasis is transmitted to humans via water snail hosts, and affects about 200 million people. Snails and slugs can also be serious pests, and accidental or deliberate introduction of some snail species into new environments has seriously damaged some ecosystems. The words mollusc and mollusk are both derived from the French mollusque, which originated from the Latin molluscus, from mollis, molluscus was itself an adaptation of Aristotles τα μαλακά, the soft things, which he applied to cuttlefish. The scientific study of molluscs is accordingly called malacology, as it is now known these groups have no relation to molluscs, and very little to one another, the name Molluscoida has been abandoned. The most universal features of the structure of molluscs are a mantle with a significant cavity used for breathing and excretion
Mollusc
Mollusc
–
Cornu aspersum (formerly Helix aspersa) – a common land
snail
Mollusc
–
About 80% of all known mollusc species are
gastropods (
snails and
slugs), including this
cowry (a sea snail).
Mollusc
–
The use of
love darts by the land snail
Monachoides vicinus is a form of
sexual selection
36.
Henry Watson Fowler
–
Henry Watson Fowler was an English schoolmaster, lexicographer and commentator on the usage of the English language. He is notable for both A Dictionary of Modern English Usage and his work on the Concise Oxford Dictionary, and was described by The Times as a lexicographical genius. After an Oxford education, Fowler was a schoolmaster until his age and then worked in London as a freelance writer and journalist. In partnership with his brother Francis, and beginning in 1906, he began publishing seminal grammar, style, after his brothers death in 1918, he completed the works on which they had collaborated and edited additional works. Fowler was born on 10 March 1858 in Tonbridge, Kent and his parents, the Rev. Robert Fowler and his wife Caroline, née Watson, were originally from Devon. Robert Fowler was a Cambridge graduate, clergyman, and schoolmaster, at the time of Henrys birth he was teaching mathematics at Tonbridge School, but the family soon moved to nearby Tunbridge Wells. Henry was the eldest child of seven, and his fathers death in 1879 left him to assume a leading role in caring for his younger brothers. Henry Fowler spent some time at a school in Germany before enrolling at Rugby School in 1871. He concentrated on Latin and Greek, winning a prize for his translation into Greek verse of part of Percy Bysshe Shelleys play Prometheus Unbound. He also took part in drama and debating and in his final year served as head of his house and he was greatly inspired by one of his classics teachers, Robert Whitelaw, with whom he kept up a correspondence later in life. In 1877 Fowler began attending Balliol College, Oxford and he did not excel at Oxford as he had at Rugby, earning only second-class honours in both Moderations and Literae Humaniores. Although he participated little in Oxford sport, he did begin a practice that he was to continue for the rest of his life and he left Oxford in 1881, but was not awarded a degree until 1886, because he failed to pass his Divinity examination. Trusting in the judgement of the Balliol College master that he had an aptitude for the profession of Schoolmaster, Fowler took up a temporary teaching position at Fettes College in Edinburgh. After spending two terms there, he moved again to Yorkshire to begin a mastership at Sedbergh School in 1882. There he taught Latin, Greek and English, starting with the first form and he was a respected but uninspiring teacher, earning the nickname Joey Stinker owing to his propensity for tobacco smoking. Several of the Fowler brothers were reunited at Sedbergh, charles Fowler taught temporarily at the school during the illness of one of the house masters. Arthur Fowler had transferred from Rugby to Sedbergh for his last eighteen months at school, Henry Fowler made several lifelong friends at Sedbergh, who often accompanied him on holiday to the Alps. Despite being the son of a clergyman, Fowler had been an atheist for quite some time and he had the chance of becoming a housemaster at Sedbergh on three occasions
Henry Watson Fowler
–
Rugby School, where Fowler studied from 1871 to 1877
Henry Watson Fowler
–
Sedbergh School, where Fowler taught for two decades
37.
Philology
–
Philology is the study of language in written historical sources, it is a combination of literary criticism, history, and linguistics. It is more defined as the study of literary texts and written records, the establishment of their authenticity and their original form. A person who pursues this kind of study is known as a philologist, in older usage, especially British, philology is more general, covering comparative and historical linguistics. Indo-European studies involves the comparative philology of all Indo-European languages, Philology, with its focus on historical development, is contrasted with linguistics due to Ferdinand de Saussures insistence on the importance of synchronic analysis. The contrast continued with the emergence of structuralism and Chomskyan linguistics alongside its emphasis on syntax, the term changed little with the Latin philologia, and later entered the English language in the 16th century, from the Middle French philologie, in the sense of love of literature. The adjective φιλόλογος meant fond of discussion or argument, talkative, in Hellenistic Greek also implying an excessive preference of argument over the love of true wisdom, as an allegory of literary erudition, Philologia appears in 5th-century post-classical literature, an idea revived in Late Medieval literature. The meaning of love of learning and literature was narrowed to the study of the development of languages in 19th-century usage of the term. Most continental European countries still maintain the term to designate departments, colleges, position titles, J. R. R. Tolkien opposed the nationalist reaction against philological practices, claiming that the philological instinct was universal as is the use of language. Based on the critique of Friedrich Nietzsche, US scholars since the 1980s have viewed philology as responsible for a narrowly scientistic study of language. The comparative linguistics branch of philology studies the relationship between languages, similarities between Sanskrit and European languages were first noted in the early 16th century and led to speculation of a common ancestor language from which all these descended. Philology also includes the study of texts and their history and it includes elements of textual criticism, trying to reconstruct an authors original text based on variant copies of manuscripts. Since that time, the principles of textual criticism have been improved and applied to other widely distributed texts such as the Bible. Scholars have tried to reconstruct the original readings of the Bible from the manuscript variants and this method was applied to Classical Studies and to medieval texts as a way to reconstruct the authors original work. A related study method known as higher criticism studies the authorship, date, as these philological issues are often inseparable from issues of interpretation, there is no clear-cut boundary between philology and hermeneutics. When text has a significant political or religious influence, scholars have difficulty reaching objective conclusions, some scholars avoid all critical methods of textual philology, especially in historical linguistics, where it is important to study the actual recorded materials. Supporters of New Philology insist on a diplomatic approach, a faithful rendering of the text exactly as found in the manuscript. Another branch of philology, cognitive philology, studies written and oral texts and this science compares the results of textual science with the results of experimental research of both psychology and artificial intelligence production systems. In the case of Bronze Age literature, philology includes the prior decipherment of the language under study and this has notably been the case with the Egyptian, Sumerian, Assyrian, Hittite, Ugaritic and Luwian languages
Philology
–
Cover of Indo-European philology historical and comparative by
William Burley Lockwood
38.
Eocene
–
The Eocene Epoch, lasting from 56 to 33.9 million years ago, is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. As with other periods, the strata that define the start and end of the epoch are well identified. The name Eocene comes from the Ancient Greek ἠώς and καινός, the Eocene epoch is conventionally divided into early, middle, and late subdivisions. The corresponding rocks are referred to as lower, middle, the Ypresian stage constitutes the lower, the Priabonian stage the upper, and the Lutetian and Bartonian stages are united as the middle Eocene. The Eocene Epoch contained a variety of different climate conditions that includes the warmest climate in the Cenozoic Era. During this period of time, little to no ice was present on Earth with a difference in temperature from the equator to the poles. Following the maximum was a descent into an icehouse climate from the Eocene Optimum to the Eocene-Oligocene transition at 34 million years ago. During this decrease ice began to reappear at the poles, greenhouse gases, in particular carbon dioxide and methane, played a significant role during the Eocene in controlling the surface temperature. For the early Eocene there is discussion on how much carbon dioxide was in the atmosphere. This is due to numerous proxies representing different atmospheric carbon dioxide content, for contrast, today the carbon dioxide levels are at 400 ppm or 0. 04%. At about the beginning of the Eocene Epoch the amount of oxygen in the atmosphere more or less doubled. During the early Eocene, methane was another gas that had a drastic effect on the climate. In comparison to carbon dioxide, methane has much effect on temperature as methane is ~34 times more effective per molecule than carbon dioxide on a 100-year scale. Most of the methane released to the atmosphere during this period of time would have been from wetlands, swamps, the atmospheric methane concentration today is 0. 000179% or 1.79 ppmv. Due to the climate and sea level rise associated with the early Eocene, more wetlands, more forests. Comparing the early Eocene production of methane to current levels of atmospheric methane, biogenic production of methane produces carbon dioxide and water vapor along with the methane, as well as yielding infrared radiation
Eocene
–
Eocene fauna of North America
Eocene
–
Crassostrea gigantissima (Finch, 1824), a giant oyster from the Eocene of
Texas.
Eocene
–
Fossil nummulitid
foraminiferans showing microspheric and megalospheric individuals; Eocene of the
United Arab Emirates; scale in mm.
Eocene
–
Basilosaurus
39.
Paleocene
–
The Paleocene or Palaeocene, the old recent, is a geologic epoch that lasted from about 66 to 56 million years ago. It is the first epoch of the Paleogene Period in the modern Cenozoic Era, as with many geologic periods, the strata that define the epochs beginning and end are well identified, but the exact ages remain uncertain. The Paleocene Epoch brackets two major events in Earths history and it started with the mass extinction event at the end of the Cretaceous, known as the Cretaceous–Paleogene boundary. This was a marked by the demise of non-avian dinosaurs, giant marine reptiles and much other fauna. The die-off of the dinosaurs left unfilled ecological niches worldwide, the Paleocene ended with the Paleocene–Eocene Thermal Maximum, a geologically brief interval characterized by extreme changes in climate and carbon cycling. The name Paleocene comes from Ancient Greek and refers to the old new fauna that arose during the epoch. The K–Pg boundary that marks the separation between Cretaceous and Paleocene is visible in the record of much of the Earth by a discontinuity in the fossil fauna. There is also evidence of abrupt changes in flora and fauna. There is some evidence that a substantial but very short-lived climatic change may have happened in the early decades of the Paleocene. The end of the Paleocene was also marked by a time of major change, the Paleocene–Eocene Thermal Maximum upset oceanic and atmospheric circulation and led to the extinction of numerous deep-sea benthic foraminifera and a major turnover in mammals on land. The Paleocene is divided into three stages, the Danian, the Selandian and the Thanetian, as shown in the table above, additionally, the Paleocene is divided into six Mammal Paleogene zones. The early Paleocene was cooler and dryer than the preceding Cretaceous, in many ways, the Paleocene continued processes that had begun during the late Cretaceous Period. During the Paleocene, the continued to drift toward their present positions. The Laramide orogeny of the late Cretaceous continued to uplift the Rocky Mountains in the American west, africa was heading north towards Europe, slowly closing the Tethys Ocean, and India began its migration to Asia that would lead to a tectonic collision and the formation of the Himalayas. The inland seas in North America and Europe had receded by the beginning of the Paleocene, making way for new land-based flora, warm seas circulated throughout the world, including the poles. The earliest Paleocene featured a low diversity and abundance of marine life, tropical conditions gave rise to abundant marine life, including coral reefs. With the demise of marine reptiles at the end of the Cretaceous, at the end of the Cretaceous, the ammonites and many species of foraminifera became extinct. Marine fauna also came to resemble modern fauna, with only the marine mammals, terrestrial Paleocene strata immediately overlying the K–Pg boundary is in places marked by a fern spike, a bed especially rich in fern fossils
Paleocene
–
Life restoration of
Titanoides
Paleocene
–
Section of an
Asiatosuchus jaw
Paleocene
–
Gastornis
40.
Mesozoic
–
The Mesozoic Era is an interval of geological time from about 252 to 66 million years ago. This Era is also called from a paleobotanist view the Age of Conifers, Mesozoic means middle life, deriving from the Greek prefix meso-/μεσο- for between and zōon/ζῷον meaning animal or living being. It is one of three eras of the Phanerozoic Eon, preceded by the Paleozoic and succeeded by the Cenozoic. The era is subdivided into three periods, the Triassic, Jurassic, and Cretaceous, which are further subdivided into a number of epochs. The Mesozoic was a time of significant tectonic, climate and evolutionary activity, the era witnessed the gradual rifting of the supercontinent Pangaea into separate landmasses that would eventually move into their current positions. The climate of the Mesozoic was varied, alternating between warming and cooling periods, overall, however, the Earth was hotter than it is today. Birds first appeared in the Jurassic, having evolved from a branch of theropod dinosaurs, the first mammals also appeared during the Mesozoic, but would remain small—less than 15 kg —until the Cenozoic. Following the Paleozoic, the Mesozoic extended roughly 186 million years and this time frame is separated into three geologic periods. It is also known as the Great Dying because it is considered the largest mass extinction in the Earths history, the upper boundary of the Mesozoic is set at the Cretaceous–Paleogene extinction event, which may have been caused by the impactor that created Chicxulub Crater on the Yucatán Peninsula. Towards the Late Cretaceous large volcanic eruptions are believed to have contributed to the Cretaceous–Paleogene extinction event. Approximately 50% of all genera became extinct, including all of the non-avian dinosaurs, the Triassic ranges roughly from 252 million to 201 million years ago. The Triassic is a time in Earths history bracketed between the Permian Extinction and the Triassic–Jurassic extinction event, two of the big five, and precedes the Jurassic Period and it has three major epochs, the Early Triassic, the Middle Triassic and the Late Triassic. The Early Triassic was between about 252 million to 247 million years ago and was dominated by deserts as Pangaea had not yet broken up, thus the interior was nothing, the Earth had just witnessed a massive die-off in which 95% of all life became extinct. The most common life on earth were Lystrosaurus, labyrinthodonts. Temnospondyls evolved during this time and would be the dominant predator for much of the Triassic, the Middle Triassic spans roughly from 247 million to 237 million years ago. The Middle Triassic featured the beginnings of the breakup of Pangaea, the ecosystem had recovered from the devastation that was the Great Dying. Algae, sponge, corals, and crustaceans all had recovered, new aquatic reptiles evolved, such as ichthyosaurs and nothosaurs. Meanwhile, on land, pine forests flourished, as did groups of insects like mosquitoes, the first ancient crocodilians evolved, which sparked competition with the large amphibians that had since ruled the freshwater world
Mesozoic
–
Plateosaurus (a
prosauropod)
Mesozoic
–
Rhamphorhynchus
Mesozoic
–
(Inaccurately portrayed)
Stegosaurus
Mesozoic
–
Tylosaurus (a
mosasaur) hunting
Xiphactinus
41.
Dinosaurs
–
Dinosaurs are a diverse group of reptiles of the clade Dinosauria that first appeared during the Triassic. Although the exact origin and timing of the evolution of dinosaurs is the subject of active research and they became the dominant terrestrial vertebrates after the Triassic–Jurassic extinction event 201 million years ago. Their dominance continued through the Jurassic and Cretaceous periods and ended when the Cretaceous–Paleogene extinction event led to the extinction of most dinosaur groups 66 million years ago, until the late 20th century, all groups of dinosaurs were believed to be extinct. As such, birds were the dinosaur lineage to survive the mass extinction event. This article deals primarily with non-avian dinosaurs, Dinosaurs are a varied group of animals from taxonomic, morphological and ecological standpoints. Birds, at over 10,000 living species, are the most diverse group of vertebrates besides perciform fish, using fossil evidence, paleontologists have identified over 500 distinct genera and more than 1,000 different species of non-avian dinosaurs. Dinosaurs are represented on every continent by both extant species and fossil remains, while dinosaurs were ancestrally bipedal, many extinct groups included quadrupedal species, and some were able to shift between these stances. Elaborate display structures such as horns or crests are common to all dinosaur groups, evidence suggests that egg laying and nest building are additional traits shared by all dinosaurs.7 meters and heights of 18 meters and were the largest land animals of all time. Still, the idea that dinosaurs were uniformly gigantic is a misconception based in part on preservation bias, as large. Many dinosaurs were small, Xixianykus, for example, was only about 50 cm long. Through the first half of the 20th century, before birds were recognized to be dinosaurs, most of the community believed dinosaurs to have been sluggish. Most research conducted since the 1970s, however, has indicated that all dinosaurs were active animals with elevated metabolisms and numerous adaptations for social interaction. The large sizes of some groups, as well as their seemingly monstrous and fantastic nature, have ensured dinosaurs regular appearance in best-selling books and films. Persistent public enthusiasm for the animals has resulted in significant funding for dinosaur science, the term is derived from the Greek words δεινός and σαῦρος. Though the taxonomic name has often interpreted as a reference to dinosaurs teeth, claws. Instead, dinosaurs, like many forms of reptile sub-groups, did not exhibit characteristics which were traditionally regarded as reptilian. Under phylogenetic nomenclature, dinosaurs are usually defined as the group consisting of Triceratops, Neornithes, their most recent common ancestor, Birds are now recognized as being the sole surviving lineage of theropod dinosaurs. In traditional taxonomy, birds were considered a class that had evolved from dinosaurs
Dinosaurs
Dinosaurs
–
The world's smallest dinosaur footprint, the Hunterian Museum, Glasgow.
Dinosaurs
–
Triceratops horridus skeleton,
Natural History Museum of Los Angeles County
Dinosaurs
–
The common
house sparrow (Passer domesticus) is often used to represent modern birds in definitions of the group Dinosauria.
42.
Paleozoic
–
The Paleozoic Era is the earliest of three geologic eras of the Phanerozoic Eon, from 541 to 252.17 million years ago. It is the longest of the Phanerozoic eras, and is subdivided into six periods, the Cambrian, Ordovician, Silurian, Devonian, Carboniferous. The Paleozoic comes after the Neoproterozoic era of the Proterozoic and is followed by the Mesozoic, the Paleozoic was a time of dramatic geological, climatic, and evolutionary change. The Cambrian witnessed the most rapid and widespread diversification of life in Earths history, known as the Cambrian explosion, fish, arthropods, amphibians, anapsids, synapsids, euryapsids and diapsids all evolved during the Paleozoic. Life began in the ocean but eventually transitioned onto land, and by the late Paleozoic, Great forests of primitive plants covered the continents, many of which formed the coal beds of Europe and eastern North America. Towards the end of the era, large, sophisticated diapsids and synapsids were dominant, the Paleozoic Era ended with the largest extinction event in the history of Earth, the Permian–Triassic extinction event. The effects of this catastrophe were so devastating that it took life on land 30 million years into the Mesozoic Era to recover, recovery of life in the sea may have been much faster. The Paleozoic era began and ended with supercontinents and in between were the rise of mountains along the margins, and flooding and draining of shallow seas between. At its start, the supercontinent Pannotia broke up, paleoclimatic studies and evidence of glaciers indicate that central Africa was most likely in the polar regions during the early Paleozoic. During the early Paleozoic, the huge continent Gondwana formed or was forming, by mid-Paleozoic, the collision of North America and Europe produced the Acadian-Caledonian uplifts, and a subduction plate uplifted eastern Australia. There are six periods in the Paleozoic Era, Cambrian, Ordovician, Silurian, Devonian, Carboniferous, the Cambrian spans from 541 million years to 485 million years and is the first period of the Paleozoic era of the Phanerozoic. The Cambrian marked a boom in evolution in an event known as the Cambrian explosion in which the largest number of creatures evolved in any period of the history of the Earth. Creatures like algae evolved, but the most ubiquitous of that period were the armored arthropods, almost all marine phyla evolved in this period. During this time, the supercontinent Pannotia begins to break up, the Ordovician spanned from 485 million years to 443 million years ago. The Ordovician is a time in Earths history in many of the biological classes still prevalent today evolved, such as primitive fish, cephalopods. The most common forms of life, however, were trilobites, snails, more importantly, the first arthropods went ashore to colonize the empty continent of Gondwana. By the end of the Ordovican, Gondwana was at the pole, early North America had collided with Europe. Glaciation of Africa resulted in a drop in sea level
Paleozoic
–
Trilobites
Paleozoic
–
Cephalaspis (a jawless fish)
Paleozoic
–
Eogyrinus (an amphibian) of the Carboniferous
Paleozoic
–
Dimetrodon
43.
Trilobites
–
Trilobites are a fossil group of extinct marine arachnomorph arthropods that form the class Trilobita. Trilobites form one of the earliest known groups of arthropods, Trilobites finally disappeared in the mass extinction at the end of the Permian about 250 million years ago. The trilobites were among the most successful of all early animals, by the time trilobites first appeared in the fossil record, they were already highly diversified and geographically dispersed. Because trilobites had wide diversity and an easily fossilized exoskeleton, a fossil record was left behind. The study of fossils has facilitated important contributions to biostratigraphy, paleontology, evolutionary biology. Trilobites are often placed within the arthropod subphylum Schizoramia within the superclass Arachnomorpha, Trilobites had many lifestyles, some moved over the sea bed as predators, scavengers, or filter feeders, and some swam, feeding on plankton. Most lifestyles expected of modern marine arthropods are seen in trilobites, some trilobites are even thought to have evolved a symbiotic relationship with sulfur-eating bacteria from which they derived food. The earliest trilobites known from the record are redlichiids and ptychopariid bigotinids dated to some 540 to 520 million years ago. Contenders for the earliest trilobites include Profallotaspis jakutensis, Fritzaspis spp, all trilobites are thought to have originated in present-day Siberia, with subsequent distribution and radiation from this location. All Olenellina lack facial sutures, and this is thought to represent the original state, other groups show secondary lost facial sutures, such as all Agnostina and some Phacopina. Earlier trilobites may be found and could shed light on the origin of trilobites. Three specimens of a trilobite from Morocco, Megistaspis hammondi, dated 478 million years old contain fossilized soft parts. Early trilobites show all the features of the group as a whole. Morphological similarities between early trilobites and other Cambrian arthropods make analysis of ancestral relationships difficult, however, that trilobites share a common ancestor with other arthropods before the Ediacaran-Cambrian boundary is still reasonable to assume. Changes also included narrowing of the thorax and increasing or decreasing numbers of thoracic segments, specific changes to the cephalon are also noted, variable glabella size and shape, position of eyes and facial sutures, and hypostome specialization. Several morphologies appeared independently within different major taxa, effacement, the loss of surface detail in the cephalon, pygidium, or the thoracic furrows, is also a common evolutionary trend. Notable examples of this were the orders Agnostida and Asaphida, effacement is believed to be an indication of either a burrowing lifestyle or a pelagic one. Effacement poses a problem for taxonomists since the loss of details can make the determination of phylogenetic relationships difficult, tectonic breakup of Pannotia then allowed for the diversification and radiation expressed later in the Cambrian as the distinctive olenellid province and the separate redlichid province
Trilobites
Trilobites
Trilobites
–
Redlichida, such as this
Paradoxides, may represent the ancestral trilobites.
Trilobites
–
Walliserops trifurcatus, from Djebel Oufaten, Morocco
44.
Coal forest
–
Coal forests were the vast swathes of wetlands that covered much of the Earths tropical land areas during the late Carboniferous and Permian times. As vegetable matter from these forests decayed, enormous deposits of peat accumulated, much of the carbon in the peat deposits produced by coal forests came from photosynthetic splitting of existing carbon dioxide, which released the accompanying split-off oxygen into the atmosphere. Coal forests covered tropical Euramerica and Cathaysia, climate change devastated these tropical rainforests during the Carboniferous period. The Carboniferous Rainforest Collapse was caused by a drier climate that initially fragmented. During most of the rest of Carboniferous times, the forests were mainly restricted to refugia in North America. At the very end of the Carboniferous period, the forests underwent a resurgence, expanding mainly in eastern Asia, notably China. The Chinese coal forests continued to flourish well into Permian times, the coal forests seem to have been areas of flat, low-lying swampy areas with rivers flowing through from higher, drier land. When the rivers flooded, silt built up into natural levees. Lakes formed as some areas subsided, while formerly wet areas became dry from silt buildups, when a forested area became dry enough to be set on fire by lightning, the resulting forest fire left charcoal, the fusain component of coal. There seems to have been a rich and varied flora, with sets of species for each type of growing condition, the most varied flora seems to have been levee vegetation, with many species of trees, bushes, creepers, etc. Thickets of Calamites seem to have favored the edges of lakes, lycopsid genera specialized in various roles, Paralycopodites as a pioneer on newly silted lakes shallow enough for land vegetation to start, Diaphorodendron later when the ground had become peaty. Other species specialized in re-settling land which had been deforested by flooding, Synchysidendron and Lepidodendron in mineral-soil areas. Cordaites may have favored drier areas of the swamp, one author thinks that Sigillaria favored the intermediate areas between levee habitat and swamp habitat. In the later part of this period tree ferns tended to take over from lycopsid trees. g, Sigillaria 33, Lepidodendron 19, Alethopteris 11, Calamites 8. Some easily identified species occur over an area but only for a small part of the coal-forming period. Animals inhabiting the forests were invertebrates, fish, labyrinthodont amphibians. An example of plant-eating was evidenced by tree lycopsid tracheids found in an Arthropleuras gut and these films and TV series are set partly in coal forests, Prehistoric Park Episode 5, Walking with Monsters Episode Two, Reptiles Beginnings Coal forest. Department of Earth and Environmental Sciences, The Open University, University of California Museum of Paleontology
Coal forest
–
Etching depicting some of the most significant plants of the
Carboniferous.
Coal forest
–
Coal forest of
tree ferns and
lycopod trees, in a 1906 artist's rendering
45.
Synapsida
–
Synapsids, synonymous with theropsids, are a group of animals that includes mammals and every animal more closely related to mammals than to other living amniotes. They are easily separated from other amniotes by having a temporal fenestra, a low in the skull roof behind each eye, leaving a bony arch beneath each. Primitive synapsids are usually called pelycosaurs or pelycosaur-grade synapsids, more advanced mammal-like ones, the non-mammalian members are described as mammal-like reptiles in classical systematics, they can also be called stem mammals or proto-mammals. Synapsids evolved from basal amniotes and are one of the two groups of the later amniotes, the other is the sauropsids, a group that includes modern reptiles. The distinctive temporal fenestra developed in the ancestral synapsid about 312 million years ago, synapsids were the largest terrestrial vertebrates in the Permian period,299 to 251 million years ago, although some of the larger pareiasaurs at the end of Permian could match them in size. As with other groups then extant, their numbers and variety were severely reduced by the Permian–Triassic extinction, by the time of the extinction at the end of Permian, all the older forms of synapsids were already gone, having been replaced by the more advanced therapsids. The cynodont group Probainognathia, which includes Mammaliaformes, were the only synapsids who outlasted the Triassic, after the Cretaceous–Paleogene extinction event, the synapsids again became the largest land animals. Synapsids were originally defined at the turn of the 20th century as one of the four main subclasses of reptiles and these openings in the cheek bones allowed the attachment of larger jaw muscles, hence a more efficient bite. The traditional classification of synapsids as reptiles is continued by some palaeontologists, phylogenetically, synapsids are the entire synapsid/mammal branch of the tree of life, though in practice the term is most often used when referring to the reptile-grade synapsids. The term mammal-like reptiles represents a paraphyletic grade, but is used both colloquially and in the technical literature to refer to all non-mammalian synapsids. The actual monophyly of Synapsida is not in doubt, however, the synapsids are traditionally divided into a primitive group and an advanced group, known respectively as pelycosaurs and therapsids. Pelycosaurs make up the six most primitive families of synapsids and they were all rather lizard-like, with sprawling gait and possibly horny scutes. The therapsids contain the more advanced synapsids, having an erect pose and possibly hair. In traditional vertebrate classification, the Pelycosauria and Therapsida were both considered orders of the subclass Synapsida, in phylogenetic nomenclature, the terms are used somewhat differently, as the daughter clades are included. Most papers published during the 21st century have treated Pelycosauria as a grouping of primitive members. Therapsida has remained in use as a clade containing both the traditional families and mammals. However, in usage, the terms are used almost exclusively when referring to the more basal members that lie outside of Mammaliaformes. Synapsids evolved a temporal fenestra behind each eye orbit on the surface of the skull
Synapsida
Synapsida
–
Eothyris, an early synapsid with multiple canines
Synapsida
–
The
sea otter has the densest fur of modern mammals.
Synapsida
–
Sail-back pelycosaurs like
Edaphosaurus indicate an early trend toward temperature regulation in synapsids.
46.
Paratethys
–
The Paratethys ocean, Paratethys sea or just Paratethys was a large shallow sea that stretched from the region north of the Alps over Central Europe to the Aral Sea in Central Asia. The sea was formed during the Oxfordian stage of the Late Jurassic as an extension of the rift that formed the Central Atlantic Ocean and was isolated during the Oligocene epoch. It was separated from the Tethys Ocean to the south by the formation of the Alps, Carpathians, Dinarides, Taurus, during its long existence the Paratethys was at times reconnected with the Tethys or its successors, the Mediterranean Sea or Indian Ocean. From the Pliocene epoch onward, the Paratethys became progressively shallower, todays Black Sea, Caspian Sea, Aral Sea, Lake Urmia, Namak Lake and others are remnants of the Paratethys Sea. The name Paratethys was first used by V. D. Laskarev in 1924, laskarevs definition included only fossils and sedimentary strata from the sea of the Neogene system. This definition was later adjusted to include the Oligocene series. The existence of a water body in these periods was deduced from fossil fauna. In periods in which the Paratethys or parts of it were separated from other or from other oceans. In this way the development of the Paratethys can be studied. Sedimentary strata from the Paratethys are difficult to correlate with those from other oceans or seas because at times it was separated from them. Stratigraphers of the Paratethys therefore have their own sets of stages which are still used as alternatives for the official geologic timescale of the ICS. The Paratethys spread over an area in Central Europe and western Asia. During the Jurassic and Cretaceous periods, this part of Eurasia was covered by shallow seas formed the northern margins of the Tethys Ocean. However, because Anatolia, the boundary of the Paleo-Tethys, is a part of the original Cimmerian continent. The Tethys ocean formed between Laurasia and Gondwana when the supercontinent Pangea broke up during the Triassic, the boundary between the Eocene and Oligocene epochs was characterized by a big drop of the global sea level and a sudden steep cooling of global climates. At the same time the Alpine orogeny, a phase by which the Alps, Carpathians, Dinarides, Taurus, Elburz. The combination of a drop in sea level and tectonic uplift resulted in a regression of the sea. Connections with the Arctic Ocean, the North Sea Basin and Atlantic Ocean also closed in the Early Oligocene, however, it is possible connections with the Rhônegraben and the Hessen Strait still kept open
Paratethys
–
P a r a t e t h y s
47.
Europe
–
Europe is a continent that comprises the westernmost part of Eurasia. Europe is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, yet the non-oceanic borders of Europe—a concept dating back to classical antiquity—are arbitrary. Europe covers about 10,180,000 square kilometres, or 2% of the Earths surface, politically, Europe is divided into about fifty sovereign states of which the Russian Federation is the largest and most populous, spanning 39% of the continent and comprising 15% of its population. Europe had a population of about 740 million as of 2015. Further from the sea, seasonal differences are more noticeable than close to the coast, Europe, in particular ancient Greece, was the birthplace of Western civilization. The fall of the Western Roman Empire, during the period, marked the end of ancient history. Renaissance humanism, exploration, art, and science led to the modern era, from the Age of Discovery onwards, Europe played a predominant role in global affairs. Between the 16th and 20th centuries, European powers controlled at times the Americas, most of Africa, Oceania. The Industrial Revolution, which began in Great Britain at the end of the 18th century, gave rise to economic, cultural, and social change in Western Europe. During the Cold War, Europe was divided along the Iron Curtain between NATO in the west and the Warsaw Pact in the east, until the revolutions of 1989 and fall of the Berlin Wall. In 1955, the Council of Europe was formed following a speech by Sir Winston Churchill and it includes all states except for Belarus, Kazakhstan and Vatican City. Further European integration by some states led to the formation of the European Union, the EU originated in Western Europe but has been expanding eastward since the fall of the Soviet Union in 1991. The European Anthem is Ode to Joy and states celebrate peace, in classical Greek mythology, Europa is the name of either a Phoenician princess or of a queen of Crete. The name contains the elements εὐρύς, wide, broad and ὤψ eye, broad has been an epithet of Earth herself in the reconstructed Proto-Indo-European religion and the poetry devoted to it. For the second part also the divine attributes of grey-eyed Athena or ox-eyed Hera. The same naming motive according to cartographic convention appears in Greek Ανατολή, Martin Litchfield West stated that phonologically, the match between Europas name and any form of the Semitic word is very poor. Next to these there is also a Proto-Indo-European root *h1regʷos, meaning darkness. Most major world languages use words derived from Eurṓpē or Europa to refer to the continent, in some Turkic languages the originally Persian name Frangistan is used casually in referring to much of Europe, besides official names such as Avrupa or Evropa
Europe
–
Reconstruction of
Herodotus ' world map
Europe
Europe
–
A medieval
T and O map from 1472 showing the three continents as domains of the sons of
Noah — Asia to Sem (
Shem), Europe to Iafeth (
Japheth), and Africa to Cham (
Ham)
Europe
–
Early modern depiction of
Europa regina ('Queen Europe') and the mythical
Europa of the 8th century BC.
48.
Great Britain
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Great Britain, also known as Britain, is a large island in the north Atlantic Ocean off the northwest coast of continental Europe. With an area of 209,331 km2, Great Britain is the largest European island, in 2011 the island had a population of about 61 million people, making it the worlds third-most populous island after Java in Indonesia and Honshu in Japan. The island of Ireland is situated to the west of it, the island is dominated by a maritime climate with quite narrow temperature differences between seasons. Politically, the island is part of the United Kingdom of Great Britain and Northern Ireland, most of England, Scotland, and Wales are on the island. The term Great Britain often extends to surrounding islands that form part of England, Scotland, and Wales. A single Kingdom of Great Britain resulted from the union of the Kingdom of England, the archipelago has been referred to by a single name for over 2000 years, the term British Isles derives from terms used by classical geographers to describe this island group. By 50 BC Greek geographers were using equivalents of Prettanikē as a name for the British Isles. However, with the Roman conquest of Britain the Latin term Britannia was used for the island of Great Britain, the oldest mention of terms related to Great Britain was by Aristotle, or possibly by Pseudo-Aristotle, in his text On the Universe, Vol. III. To quote his works, There are two large islands in it, called the British Isles, Albion and Ierne. The name Britain descends from the Latin name for Britain, Britannia or Brittānia, Old French Bretaigne and Middle English Bretayne, Breteyne. The French form replaced the Old English Breoton, Breoten, Bryten, Breten, Britannia was used by the Romans from the 1st century BC for the British Isles taken together. It is derived from the writings of the Pytheas around 320 BC. Marcian of Heraclea, in his Periplus maris exteri, described the group as αἱ Πρεττανικαὶ νῆσοι. The peoples of these islands of Prettanike were called the Πρεττανοί, Priteni is the source of the Welsh language term Prydain, Britain, which has the same source as the Goidelic term Cruithne used to refer to the early Brythonic-speaking inhabitants of Ireland. The latter were later called Picts or Caledonians by the Romans, the Greco-Egyptian scientist Ptolemy referred to the larger island as great Britain and to Ireland as little Britain in his work Almagest. The name Albion appears to have out of use sometime after the Roman conquest of Britain. After the Anglo-Saxon period, Britain was used as a term only. It was used again in 1604, when King James VI and I styled himself King of Great Brittaine, France, Great Britain refers geographically to the island of Great Britain, politically to England, Scotland and Wales in combination
Great Britain
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Satellite image of Great Britain in April 2002
Great Britain
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Prima Europe tabula. A copy of
Ptolemy 's 2nd century map of Roman Britain
Great Britain
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The
robin is popularly known as "Britain's favourite bird".
Great Britain
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Heather growing wild in the
Highlands at
Dornoch.
49.
Netherlands
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The Netherlands is the main constituent country of the Kingdom of the Netherlands. It is a densely populated country located in Western Europe with three territories in the Caribbean. The European part of the Netherlands borders Germany to the east, Belgium to the south, and the North Sea to the northwest, sharing borders with Belgium, the United Kingdom. The three largest cities in the Netherlands are Amsterdam, Rotterdam and The Hague, Amsterdam is the countrys capital, while The Hague holds the Dutch seat of parliament and government. The port of Rotterdam is the worlds largest port outside East-Asia, the name Holland is used informally to refer to the whole of the country of the Netherlands. Netherlands literally means lower countries, influenced by its low land and flat geography, most of the areas below sea level are artificial. Since the late 16th century, large areas have been reclaimed from the sea and lakes, with a population density of 412 people per km2 –507 if water is excluded – the Netherlands is classified as a very densely populated country. Only Bangladesh, South Korea, and Taiwan have both a population and higher population density. Nevertheless, the Netherlands is the worlds second-largest exporter of food and agricultural products and this is partly due to the fertility of the soil and the mild climate. In 2001, it became the worlds first country to legalise same-sex marriage, the Netherlands is a founding member of the EU, Eurozone, G-10, NATO, OECD and WTO, as well as being a part of the Schengen Area and the trilateral Benelux Union. The first four are situated in The Hague, as is the EUs criminal intelligence agency Europol and this has led to the city being dubbed the worlds legal capital. The country also ranks second highest in the worlds 2016 Press Freedom Index, the Netherlands has a market-based mixed economy, ranking 17th of 177 countries according to the Index of Economic Freedom. It had the thirteenth-highest per capita income in the world in 2013 according to the International Monetary Fund, in 2013, the United Nations World Happiness Report ranked the Netherlands as the seventh-happiest country in the world, reflecting its high quality of life. The Netherlands also ranks joint second highest in the Inequality-adjusted Human Development Index, the region called Low Countries and the country of the Netherlands have the same toponymy. Place names with Neder, Nieder, Nether and Nedre and Bas or Inferior are in use in all over Europe. They are sometimes used in a relation to a higher ground that consecutively is indicated as Upper, Boven, Oben. In the case of the Low Countries / the Netherlands the geographical location of the region has been more or less downstream. The geographical location of the region, however, changed over time tremendously
Netherlands
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The Netherlands in 5500 BC
Netherlands
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Flag
Netherlands
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The Netherlands in 500 BC
Netherlands
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An oak figurine found in
Willemstad, North Brabant (4500 BC).
50.
Tegelen
–
Tegelen is a city district of the municipality of Venlo, situated in the Netherlands. It was an independent municipality until 2001, when it was merged into the municipality of Venlo, the name of the interglacial era of Tiglian is derived from Tegelen because of the many fossils found there from this era in the local clay. During excavations in Tegelen Roman pottery and tile ovens were found, the Sint-Martinus church is mentioned in diocesan and monasterial archives dating back to the year 800. Because of its location, various castles and reinforced farms were soon established. The most important of these were the Castle of Holtmühle and the De Munt, during the Middle Ages, there were several battles in and around Tegelen, because of its proximity to the walled city of Venlo. Over time, a barracks was established in Venlo, and a fortification in neighbouring Blerick, as a result, from the 16th century until the 18th century Tegelen was regularly visited by plundering armies. For centuries Tegelen was part of the Duchy of Jülich, while neighbouring Venlo belonged to the Duchy of Guelders, so literally, according to the people of Tegelen Venlo was abroad and vice versa. This explains the differences between the dialects of the neighbouring towns and the rivalry between these parts of the city that persists to this day. The black, uncrowned lion on a ground, in the coat of arms. For Jülich it was important to have access to the Meuse river. Tegelen, with its harbour at Steyl, was the most northern one, in Napoleonic times, the former duchy of Jülich became part of the Roer department. Tegelen, Sittard and Urmond were ceded to the United Kingdom of the Netherlands in 1815, early in the 19th century Tegelen developed into a regional centre of industry. At first, tile and pottery factories were established, and later that century, metallurgy, after 1900 agriculture was added to the mix. Pottery and related industries were successful in Tegelen from 1750 until World War II. Economic and social life before that war was dominated by a number of factory-owning families that would scratch each others backs. One infamous episode illustrating the way they treated their work force, the producers of clay products claimed that the embargo on Germany brought them to the brink of bankruptcy, and the only way they could survive was to drastically reduce wages. The work force went on strike but soon the strike fund was depleted, the local clergy helped negotiate a settlement allowing labourers to return to work for a salary that barely exceeded subsistence levels. It later transpired that there had never been any risk of any of the producers going bankrupt, and this is still evident from the gigantic villas in which these families lived and of which a number are still standing
Tegelen
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View of Tegelen
Tegelen
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Tegelen
Tegelen
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Castle of Holtmühle (nl) in 1988
