1.
Holocene
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The Holocene is the geological epoch that began after the Pleistocene at approximately 11,700 years before present. The term Recent has often used as an exact synonym of Holocene. The Holocene is part of the Quaternary period and its name comes from the Ancient Greek words ὅλος and καινός, meaning entirely recent. It has been identified with the current warm period, known as MIS1, given these, a new term, Anthropocene, is specifically proposed and used informally only for the very latest part of modern history involving significant human impact. It is accepted by the International Commission on Stratigraphy that the Holocene started approximately 11,700 years ago, the epoch follows the Pleistocene and the last glacial period. The Holocene can be subdivided into five time intervals, or chronozones, based on climatic fluctuations, Preboreal, Boreal, Atlantic, Subboreal and they find a general correspondence across Eurasia and North America, though the method was once thought to be of no interest. The scheme was defined for Northern Europe, but the changes were claimed to occur more widely. The periods of the include a few of the final pre-Holocene oscillations of the last glacial period. Paleontologists have not defined any faunal stages for the Holocene, if subdivision is necessary, periods of human technological development, such as the Mesolithic, Neolithic, and Bronze Age, are usually used. However, the time periods referenced by these terms vary with the emergence of those technologies in different parts of the world, climatically, the Holocene may be divided evenly into the Hypsithermal and Neoglacial periods, the boundary coincides with the start of the Bronze Age in Europe. According to some scholars, a division, the Anthropocene, has now begun. Continental motions due to plate tectonics are less than a kilometre over a span of only 10,000 years, however, ice melt caused world sea levels to rise about 35 m in the early part of the Holocene. The sea level rise and temporary land depression allowed temporary marine incursions into areas that are now far from the sea, Holocene marine fossils are known, for example, from Vermont and Michigan. Other than higher-latitude temporary marine incursions associated with depression, Holocene fossils are found primarily in lakebed, floodplain. Holocene marine deposits along low-latitude coastlines are rare because the rise in sea levels during the period exceeds any likely tectonic uplift of non-glacial origin, post-glacial rebound in the Scandinavia region resulted in the formation of the Baltic Sea. The region continues to rise, still causing weak earthquakes across Northern Europe, the equivalent event in North America was the rebound of Hudson Bay, as it shrank from its larger, immediate post-glacial Tyrrell Sea phase, to near its present boundaries. Climate has been stable over the Holocene. It appears that this was influenced by the glacial ice remaining in the Northern Hemisphere until the later date
2.
Megaannum
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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
3.
Precambrian
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The Precambrian is the earliest period of Earths history, set before the current Phanerozoic Eon. The Precambrian is a supereon that is subdivided into three eons of the time scale. It spans from the formation of Earth about 4.6 billion years ago to the beginning of the Cambrian Period, about 541 million years ago, the Precambrian accounts for 89% of geologic time. Relatively little is known about the Precambrian, despite it making up roughly seven-eighths of the Earths history, the Precambrian fossil record is poorer than that of the succeeding Phanerozoic, and fossils from that time are of limited biostratigraphic use. This is because many Precambrian rocks have been metamorphosed, obscuring their origins, while others have been destroyed by erosion. A stable crust was apparently in place by 4,412 Ma, the term Precambrian is recognized by the International Commission on Stratigraphy as a general term including the Archean and Proterozoic eons. It is still used by geologists and paleontologists for general discussions not requiring the more specific eon names and it was briefly called the Cryptozoic eon. A specific date for the origin of life has not been determined, carbon found in 3.8 billion year old rocks from islands off western Greenland may be of organic origin. Well-preserved microscopic fossils of bacteria older than 3.46 billion years have found in Western Australia. Probable fossils 100 million years older have been found in the same area, there is a fairly solid record of bacterial life throughout the remainder of the Precambrian. The oldest fossil evidence from that era of such complex life comes from the Lantian formation of the Ediacarian period, a very diverse collection of soft-bodied forms is found in a variety of locations worldwide and date to between 635 and 542 Ma. These are referred to as Ediacaran or Vendian biota, hard-shelled creatures appeared toward the end of that time span, marking the beginning of the Phanerozoic era. By the middle of the following Cambrian period, a diverse fauna is recorded in the Burgess Shale. The explosion in diversity of lifeforms during the early Cambrian is called the Cambrian explosion of life, while land seems to have been devoid of plants and animals, cyanobacteria and other microbes formed prokaryotic mats that covered terrestrial areas. Evidence of the details of plate motions and other activity in the Precambrian has been poorly preserved. It is generally believed that small proto-continents existed prior to 4280 Ma, the supercontinent, known as Rodinia, broke up around 750 Ma. A number of glacial periods have been identified going as far back as the Huronian epoch, one of the best studied is the Sturtian-Varangian glaciation, around 850–635 Ma, which may have brought glacial conditions all the way to the equator, resulting in a Snowball Earth. The atmosphere of the early Earth is not well understood, most geologists believe it was composed primarily of nitrogen, carbon dioxide, and other relatively inert gases, and was lacking in free oxygen
4.
Cambrian
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The Cambrian Period was the first geological period of the Paleozoic Era, of the Phanerozoic Eon. The Cambrian lasted 55.6 million years from the end of the preceding Ediacaran Period 541 million years ago to the beginning of the Ordovician Period 485.4 mya and its subdivisions, and its base, are somewhat in flux. The period was established by Adam Sedgwick, who named it after Cambria, the Latinised form of Cymru, the Welsh name for Wales, as a result, our understanding of the Cambrian biology surpasses that of some later periods. The rapid diversification of lifeforms in the Cambrian, known as the Cambrian explosion, most of the continents were probably dry and rocky due to a lack of vegetation. Shallow seas flanked the margins of several continents created during the breakup of the supercontinent Pannotia, the seas were relatively warm, and polar ice was absent for much of the period. The United States Federal Geographic Data Committee uses a barred capital C ⟨Є⟩ character similar to the capital letter Ukrainian Ye ⟨Є⟩ to represent the Cambrian Period, the proper Unicode character is U+A792 Ꞓ LATIN CAPITAL LETTER C WITH BAR. Despite the long recognition of its distinction from younger Ordovician Period rocks and older Supereon Precambrian rocks, the base of the Cambrian lies atop a complex assemblage of trace fossils known as the Treptichnus pedum assemblage. Pedum in Namibia, Spain and Newfoundland, and possibly, in the western USA, the stratigraphic range of T. pedum overlaps the range of the Ediacaran fossils in Namibia, and probably in Spain. The Cambrian Period followed the Ediacaran Period and was followed by the Ordovician Period, the Cambrian is divided into four epochs and ten ages. Currently only two series and five stages are named and have a GSSP, because the international stratigraphic subdivision is not yet complete, many local subdivisions are still widely used. In some of these subdivisions the Cambrian is divided into three epochs with locally differing names – the Early Cambrian, Middle Cambrian and Furongian, rocks of these epochs are referred to as belonging to the Lower, Middle, or Upper Cambrian. Trilobite zones allow biostratigraphic correlation in the Cambrian, each of the local epochs is divided into several stages. The International Commission on Stratigraphy list the Cambrian period as beginning at 541 million years ago, the lower boundary of the Cambrian was originally held to represent the first appearance of complex life, represented by trilobites. The recognition of small shelly fossils before the first trilobites, and Ediacara biota substantially earlier and this formal designation allowed radiometric dates to be obtained from samples across the globe that corresponded to the base of the Cambrian. Early dates of 570 million years ago quickly gained favour, though the used to obtain this number are now considered to be unsuitable. A more precise date using modern radiometric dating yield a date of 541 ±0.3 million years ago, most continental land was clustered in the Southern Hemisphere at this time, but was drifting north. Large, high-velocity rotational movement of Gondwana appears to have occurred in the Early Cambrian, the sea levels fluctuated somewhat, suggesting there were ice ages, associated with pulses of expansion and contraction of a south polar ice cap. In Baltoscandia a Lower Cambrian transgression transformed large swathes of the Sub-Cambrian peneplain into a epicontinental sea, the Earth was generally cold during the early Cambrian, probably due to the ancient continent of Gondwana covering the South Pole and cutting off polar ocean currents
5.
Ordovician
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The Ordovician is a geologic period and system, the second of six periods of the Paleozoic Era. The Ordovician spans 41.2 million years from the end of the Cambrian Period 485.4 million years ago to the start of the Silurian Period 443.8 Mya. Lapworth recognized that the fauna in the disputed strata were different from those of either the Cambrian or the Silurian periods. It received international sanction in 1960, when it was adopted as a period of the Paleozoic Era by the International Geological Congress. Life continued to flourish during the Ordovician as it did in the earlier Cambrian period, invertebrates, namely molluscs and arthropods, dominated the oceans. The Great Ordovician Biodiversification Event considerably increased the diversity of life, fish, the worlds first true vertebrates, continued to evolve, and those with jaws may have first appeared late in the period. Life had yet to diversify on land, about 100 times as many meteorites struck the Earth during the Ordovician compared with today. The Ordovician Period began with a major extinction called the Cambrian–Ordovician extinction event and it lasted for about 42 million years and ended with the Ordovician–Silurian extinction event, about 443.8 Mya which wiped out 60% of marine genera. The dates given are recent radiometric dates and vary slightly from those found in other sources and this second period of the Paleozoic era created abundant fossils that became major petroleum and gas reservoirs. The boundary chosen for the beginning of both the Ordovician Period and the Tremadocian stage is highly significant and it correlates well with the occurrence of widespread graptolite, conodont, and trilobite species. The base of the Tremadocian allows scientists to relate these species not only to each other and this makes it easier to place many more species in time relative to the beginning of the Ordovician Period. A number of terms have been used to subdivide the Ordovician Period. In 2008, the ICS erected an international system of subdivisions. There exist Baltoscandic, British, Siberian, North American, Australian, the Ordovician Period in Britain was traditionally broken into Early, Middle and Late epochs. The corresponding rocks of the Ordovician System are referred to as coming from the Lower, Middle, the Floian corresponds to the lower Arenig, the Arenig continues until the early Darriwilian, subsuming the Dapingian. The Llanvirn occupies the rest of the Darriwilian, and terminates with it at the base of the Late Ordovician. The Sandbian represents the first half of the Caradoc, the Caradoc ends in the mid-Katian, during the Ordovician, the southern continents were collected into Gondwana. Gondwana started the period in equatorial latitudes and, as the period progressed, drifted toward the South Pole, the small continent Avalonia separated from Gondwana and began to move north towards Baltica and Laurentia, opening the Rheic Ocean between Gondwana and Avalonia
6.
Silurian
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The Silurian is a geologic period and system spanning 24.6 million years from the end of the Ordovician Period, at 443.8 million years ago, to the beginning of the Devonian Period,419.2 Mya. As with other periods, the rock beds that define the periods start and end are well identified. The base of the Silurian is set at a major Ordovician-Silurian extinction event when 60% of marine species were wiped out, a significant evolutionary milestone during the Silurian was the diversification of jawed and bony fish. However, terrestrial life would not greatly diversify and affect the landscape until the Devonian, the Silurian system was first identified by British geologist Sir Roderick Impey Murchison, who was examining fossil-bearing sedimentary rock strata in south Wales in the early 1830s. He named the sequences for a Celtic tribe of Wales, the Silures, inspired by his friend Adam Sedgwick and this naming does not indicate any correlation between the occurrence of the Silurian rocks and the land inhabited by the Silures. As it was first identified, the Silurian series when traced farther afield quickly came to overlap Sedgwicks Cambrian sequence, however, charles Lapworth resolved the conflict by defining a new Ordovician system including the contested beds. An early alternative name for the Silurian was Gotlandian after the strata of the Baltic island of Gotland, the French geologist Joachim Barrande, building on Murchisons work, used the term Silurian in a more comprehensive sense than was justified by subsequent knowledge. He divided the Silurian rocks of Bohemia into eight stages and his interpretation was questioned in 1854 by Edward Forbes, and the later stages of Barrande, F, G and H, have since been shown to be Devonian. Despite these modifications in the groupings of the strata, it is recognized that Barrande established Bohemia as a classic ground for the study of the earliest fossils. The epoch is named for the town of Llandovery in Carmarthenshire, the Wenlock, which lasted from 433.4 ±1.5 to 427.4 ±2.8 mya, is subdivided into the Sheinwoodian and Homerian ages. It is named after Wenlock Edge in Shropshire, England, during the Wenlock, the oldest known tracheophytes of the genus Cooksonia, appear. The first terrestrial animals also appear in the Wenlock, represented by air-breathing millipedes from Scotland. The Ludlow, lasting from 427.4 ±1.5 to 423 ±2.8 mya, comprises the Gorstian stage, lasting until 425.6 million years ago, and it is named for the town of Ludlow in Shropshire, England. The Pridoli, lasting from 423 ±1.5 to 419.2 ±2.8 mya, is the final and it is named after one locality at the Homolka a Přídolí nature reserve near the Prague suburb Slivenec in the Czech Republic. Přídolí is the old name of a field area. The high sea levels of the Silurian and the flat land resulted in a number of island chains. The southern continents remained united during this period, the melting of icecaps and glaciers contributed to a rise in sea level, recognizable from the fact that Silurian sediments overlie eroded Ordovician sediments, forming an unconformity. The continents of Avalonia, Baltica, and Laurentia drifted together near the equator and this event is the Caledonian orogeny, a spate of mountain building that stretched from New York State through conjoined Europe and Greenland to Norway
7.
Devonian
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The Devonian is a geologic period and system of the Paleozoic, spanning 60 million years from the end of the Silurian,419.2 million years ago, to the beginning of the Carboniferous,358.9 Mya. It is named after Devon, England, where rocks from this period were first studied, the first significant adaptive radiation of life on dry land occurred during the Devonian. Free-sporing vascular plants began to spread across dry land, forming extensive forests which covered the continents, by the middle of the Devonian, several groups of plants had evolved leaves and true roots, and by the end of the period the first seed-bearing plants appeared. Various terrestrial arthropods also became well-established, Fish reached substantial diversity during this time, leading the Devonian to often be dubbed the Age of Fish. The first ray-finned and lobe-finned bony fish appeared, while the placodermi began dominating almost every aquatic environment. The ancestors of all four-limbed vertebrates began adapting to walking on land, as their strong pectoral, in the oceans, primitive sharks became more numerous than in the Silurian and Late Ordovician. The first ammonites, species of molluscs, appeared, trilobites, the mollusk-like brachiopods and the great coral reefs, were still common. The Late Devonian extinction which started about 375 million years ago severely affected marine life, killing off all placodermi, and all trilobites, save for a few species of the order Proetida. The palaeogeography was dominated by the supercontinent of Gondwana to the south, the continent of Siberia to the north, while the rock beds that define the start and end of the Devonian period are well identified, the exact dates are uncertain. According to the International Commission on Stratigraphy, the Devonian extends from the end of the Silurian 419.2 Mya, another common term is Age of the Fishes, referring to the evolution of several major groups of fish that took place during the period. Older literature on the Anglo-Welsh basin divides it into the Downtonian, Dittonian, Breconian and Farlovian stages, in the Late Devonian, by contrast, arid conditions were less prevalent across the world and temperate climates were more common. The Devonian Period is formally broken into Early, Middle and Late subdivisions, the rocks corresponding to those epochs are referred to as belonging to the Lower, Middle and Upper parts of the Devonian System. Early Devonian The Early Devonian lasted from 419.2 ±2.8 to 393.3 ±2.5 and began with the Lochkovian stage, which lasted until the Pragian. It spanned from 410.8 ±2.8 to 407.6 ±2.5, and was followed by the Emsian, which lasted until the Middle Devonian began,393. 3±2.7 million years ago. Middle Devonian The Middle Devonian comprised two subdivisions, first the Eifelian, which gave way to the Givetian 387. 7±2.7 million years ago. Late Devonian Finally, the Late Devonian started with the Frasnian,382.7 ±2.8 to 372.2 ±2.5, during which the first forests took shape on land. The first tetrapods appeared in the record in the ensuing Famennian subdivision. This lasted until the end of the Devonian,358. 9±2.5 million years ago, the Devonian was a relatively warm period, and probably lacked any glaciers
8.
Carboniferous
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The Carboniferous is a geologic period and system that spans 60 million years from the end of the Devonian Period 358.9 million years ago, to the beginning of the Permian Period,298.9 Mya. The name Carboniferous means coal-bearing and derives from the Latin words carbō and ferō, and was coined by geologists William Conybeare and William Phillips in 1822. Based on a study of the British rock succession, it was the first of the system names to be employed. The Carboniferous is often treated in North America as two periods, the earlier Mississippian and the later Pennsylvanian. Terrestrial life was established by the Carboniferous period. Amphibians were the dominant land vertebrates, of one branch would eventually evolve into amniotes. Arthropods were also common, and many were much larger than those of today. Vast swaths of forest covered the land, which would eventually be laid down, the atmospheric content of oxygen also reached their highest levels in geological history during the period, 35% compared with 21% today, allowing terrestrial invertebrates to evolve to great size. A major marine and terrestrial extinction event, the Carboniferous rainforest collapse, occurred in the middle of the period, the later half of the period experienced glaciations, low sea level, and mountain building as the continents collided to form Pangaea. In the United States the Carboniferous is usually broken into Mississippian and Pennsylvanian subperiods, the Silesian is roughly contemporaneous with the late Mississippian Serpukhovian plus the Pennsylvanian. In Britain the Dinantian is traditionally known as the Carboniferous Limestone, the Namurian as the Millstone Grit, and the Westphalian as the Coal Measures and Pennant Sandstone. There was also a drop in south polar temperatures, southern Gondwanaland was glaciated throughout the period and these conditions apparently had little effect in the deep tropics, where lush swamps, later to become coal, flourished to within 30 degrees of the northernmost glaciers. Mid-Carboniferous, a drop in sea level precipitated a major extinction, one that hit crinoids. This sea level drop and the unconformity in North America separate the Mississippian subperiod from the Pennsylvanian subperiod. This happened about 323 million years ago, at the onset of the Permo-Carboniferous Glaciation, the Carboniferous was a time of active mountain-building, as the supercontinent Pangaea came together. The southern continents remained tied together in the supercontinent Gondwana, which collided with North America–Europe along the present line of eastern North America, in the same time frame, much of present eastern Eurasian plate welded itself to Europe along the line of the Ural mountains. Most of the Mesozoic supercontinent of Pangea was now assembled, although North China, the Late Carboniferous Pangaea was shaped like an O. There were two major oceans in the Carboniferous—Panthalassa and Paleo-Tethys, which was inside the O in the Carboniferous Pangaea, other minor oceans were shrinking and eventually closed - Rheic Ocean, the small, shallow Ural Ocean and Proto-Tethys Ocean
9.
Permian
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The Permian is a geologic period and system which spans 46.7 million years from the end of the Carboniferous Period 298.9 million years ago, to the beginning of the Triassic Period 252.2 Mya. It is the last period of the Paleozoic Era, the following Triassic Period belongs to the Mesozoic Era, the concept of the Permian was introduced in 1841 by geologist Sir Roderick Murchison, who named it after the city of Perm. The Permian witnessed the diversification of the early amniotes into the groups of the mammals, turtles, lepidosaurs. The world at the time was dominated by two known as Pangaea and Siberia, surrounded by a global ocean called Panthalassa. The Carboniferous rainforest collapse left behind vast regions of desert within the continental interior, amniotes, who could better cope with these drier conditions, rose to dominance in place of their amphibian ancestors. The Permian ended with the Permian–Triassic extinction event, the largest mass extinction in Earths history, in which nearly 90% of marine species and it would take well into the Triassic for life to recover from this catastrophe. Recovery from the Permian-Triassic extinction event was protracted, on land, the term Permian was introduced into geology in 1841 by Sir R. I. Murchison, president of the Geological Society of London, who identified typical strata in extensive Russian explorations undertaken with Edouard de Verneuil, the region now lies in the Perm Krai of Russia. This could have in part caused the extinctions of marine species at the end of the period by severely reducing shallow coastal areas preferred by many marine organisms. During the Permian, all the Earths major landmasses were collected into a supercontinent known as Pangaea. The Cimmeria continent rifted away from Gondwana and drifted north to Laurasia, a new ocean was growing on its southern end, the Tethys Ocean, an ocean that would dominate much of the Mesozoic Era. Large continental landmass interiors experience climates with extreme variations of heat and cold, deserts seem to have been widespread on Pangaea. Such dry conditions favored gymnosperms, plants with seeds enclosed in a cover, over plants such as ferns that disperse spores in a wetter environment. The first modern trees appeared in the Permian, the climate in the Permian was quite varied. At the start of the Permian, the Earth was still in an Ice Age, glaciers receded around the mid-Permian period as the climate gradually warmed, drying the continents interiors. In the late Permian period, the drying continued although the temperature cycled between warm and cool cycles, Permian marine deposits are rich in fossil mollusks, echinoderms, and brachiopods. By the close of the Permian, trilobites and a host of other groups became extinct. Terrestrial life in the Permian included diverse plants, fungi, arthropods, the period saw a massive desert covering the interior of Pangaea
10.
Triassic
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The Triassic is a geologic period and system which spans 50.9 million years from the end of the Permian Period 252.17 million years ago, to the beginning of the Jurassic Period 201.3 Mya. The Triassic is the first period of the Mesozoic Era, both the start and end of the period are marked by major extinction events. Therapsids and archosaurs were the terrestrial vertebrates during this time. A specialized subgroup of archosaurs, called dinosaurs, first appeared in the Late Triassic, the vast supercontinent of Pangaea existed until the mid-Triassic, after which it began to gradually rift into two separate landmasses, Laurasia to the north and Gondwana to the south. The global climate during the Triassic was mostly hot and dry, however, the climate shifted and became more humid as Pangaea began to drift apart. The end of the period was marked by yet another mass extinction, the Triassic-Jurassic extinction event. The Triassic is usually separated into Early, Middle, and Late Triassic Epochs, from the east, along the equator, the Tethys sea penetrated Pangaea, causing the Paleo-Tethys Ocean to be closed. Later in the mid-Triassic a similar sea penetrated along the equator from the west, the remaining shores were surrounded by the world-ocean known as Panthalassa. All the deep-ocean sediments laid down during the Triassic have disappeared through subduction of oceanic plates, thus, the supercontinent Pangaea was rifting during the Triassic—especially late in that period—but had not yet separated. In North America, for example, marine deposits are limited to a few exposures in the west, thus Triassic stratigraphy is mostly based on organisms that lived in lagoons and hypersaline environments, such as Estheria crustaceans. At the beginning of the Mesozoic Era, Africa was joined with Earths other continents in Pangaea, Africa shared the supercontinents relatively uniform fauna which was dominated by theropods, prosauropods and primitive ornithischians by the close of the Triassic period. Late Triassic fossils are found throughout Africa, but are common in the south than north. The time boundary separating the Permian and Triassic marks the advent of an event with global impact. At Paleorrota geopark, located in Rio Grande do Sul, Brazil, in these formations, one of the earliest dinosaurs, Staurikosaurus, as well as the mammal ancestors Brasilitherium and Brasilodon have been discovered. The Triassic continental interior climate was hot and dry, so that typical deposits are red bed sandstones and evaporites. Pangaeas large size limited the effect of the global ocean, its continental climate was highly seasonal, with very hot summers. The strong contrast between the Pangea supercontinent and the global ocean triggered intense cross-equatorial monsoons, the best studied of such episodes of humid climate, and probably the most intense and widespread, was the Carnian Pluvial Event. On land, the vascular plants included the lycophytes, the dominant cycadophytes, ginkgophyta, ferns, horsetails
11.
Jurassic
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The Jurassic is a geologic period and system that spans 56.3 million years from the end of the Triassic Period 201.3 million years ago to the beginning of the Cretaceous Period 145 Mya. The Jurassic constitutes the middle period of the Mesozoic Era, also known as the Age of Reptiles, the start of the period is marked by the major Triassic–Jurassic extinction event. The Jurassic is named after the Jura Mountains within the European Alps, by the beginning of the Jurassic, the supercontinent Pangaea had begun rifting into two landmasses, Laurasia to the north and Gondwana to the south. This created more coastlines and shifted the continental climate from dry to humid, on land, the fauna transitioned from the Triassic fauna, dominated by both dinosauromorph and crocodylomorph archosaurs, to one dominated by dinosaurs alone. The first birds also appeared during the Jurassic, having evolved from a branch of theropod dinosaurs, other major events include the appearance of the earliest lizards, and the evolution of therian mammals, including primitive placentals. Crocodilians made the transition from a terrestrial to a mode of life. The oceans were inhabited by marine reptiles such as ichthyosaurs and plesiosaurs, the chronostratigraphic term Jurassic is directly linked to the Jura Mountains. The name Jura is derived from the Celtic root jor, which was Latinised into juria, the Jurassic period is divided into the Early Jurassic, Middle, and Late Jurassic epochs. The Jurassic System, in stratigraphy, is divided into the Lower Jurassic, Middle, the separation of the term Jurassic into three sections goes back to Leopold von Buch. The Jurassic North Atlantic Ocean was relatively narrow, while the South Atlantic did not open until the following Cretaceous period, the Tethys Sea closed, and the Neotethys basin appeared. Climates were warm, with no evidence of glaciation, as in the Triassic, there was apparently no land over either pole, and no extensive ice caps existed. In contrast, the North American Jurassic record is the poorest of the Mesozoic, the Jurassic was a time of calcite sea geochemistry in which low-magnesium calcite was the primary inorganic marine precipitate of calcium carbonate. Carbonate hardgrounds were thus very common, along with calcitic ooids, calcitic cements, the first of several massive batholiths were emplaced in the northern American cordillera beginning in the mid-Jurassic, marking the Nevadan orogeny. Important Jurassic exposures are found in Russia, India, South America, Japan, Australasia. As the Jurassic proceeded, larger and more groups of dinosaurs like sauropods and ornithopods proliferated in Africa. Middle Jurassic strata are well represented nor well studied in Africa. Late Jurassic strata are also poorly represented apart from the spectacular Tendaguru fauna in Tanzania, the Late Jurassic life of Tendaguru is very similar to that found in western North Americas Morrison Formation. During the Jurassic period, the primary living in the sea were fish
12.
Cretaceous
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The Cretaceous is a geologic period and system that spans 79 million years from the end of the Jurassic Period 145 million years ago to the beginning of the Paleogene Period 66 Mya. It is the last period of the Mesozoic Era, the Cretaceous Period is usually abbreviated K, for its German translation Kreide. The Cretaceous was a period with a warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now-extinct marine reptiles, ammonites and rudists, during this time, new groups of mammals and birds, as well as flowering plants, appeared. The Cretaceous ended with a mass extinction, the Cretaceous–Paleogene extinction event, in which many groups, including non-avian dinosaurs, pterosaurs. The end of the Cretaceous is defined by the abrupt Cretaceous–Paleogene boundary, the name Cretaceous was derived from Latin creta, meaning chalk. The Cretaceous is divided into Early and Late Cretaceous epochs, or Lower and Upper Cretaceous series, in older literature the Cretaceous is sometimes divided into three series, Neocomian, Gallic and Senonian. A subdivision in eleven stages, all originating from European stratigraphy, is now used worldwide, in many parts of the world, alternative local subdivisions are still in use. As with other geologic periods, the rock beds of the Cretaceous are well identified. No great extinction or burst of diversity separates the Cretaceous from the Jurassic and this layer has been dated at 66.043 Ma. A140 Ma age for the Jurassic-Cretaceous boundary instead of the usually accepted 145 Ma was proposed in 2014 based on a study of Vaca Muerta Formation in Neuquén Basin. Víctor Ramos, one of the authors of the study proposing the 140 Ma boundary age sees the study as a first step toward formally changing the age in the International Union of Geological Sciences, due to the high sea level there was extensive space for such sedimentation. Because of the young age and great thickness of the system. Chalk is a type characteristic for the Cretaceous. It consists of coccoliths, microscopically small calcite skeletons of coccolithophores, the group is found in England, northern France, the low countries, northern Germany, Denmark and in the subsurface of the southern part of the North Sea. Chalk is not easily consolidated and the Chalk Group still consists of sediments in many places. The group also has other limestones and arenites, among the fossils it contains are sea urchins, belemnites, ammonites and sea reptiles such as Mosasaurus. In southern Europe, the Cretaceous is usually a marine system consisting of competent limestone beds or incompetent marls
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Paleogene
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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
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Neogene
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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
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Conservation status
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The conservation status of a group of organisms indicates whether the group still exists and how likely the group is to become extinct in the near future. Various systems of conservation status exist and are in use at international, multi-country, the IUCN Red List of Threatened Species is the best known worldwide conservation status listing and ranking system. Also included are species that have gone extinct since 500 AD, when discussing the IUCN Red List, the official term threatened is a grouping of three categories, critically endangered, endangered, and vulnerable. Widespread and abundant taxa are included in this category, Data deficient – Not enough data to make an assessment of its risk of extinction Not evaluated – Has not yet been evaluated against the criteria. The Convention on International Trade in Endangered Species of Wild Fauna and Flora aims to ensure that trade in specimens of wild animals. Many countries require CITES permits when importing plants and animals listed on CITES, in the European Union, the Birds and Habitats Directives are the legal instruments that evaluate the conservation status within the EU of species and habitats. NatureServe conservation status focuses on Latin America, United States, Canada, and it has been developed by scientists from NatureServe, The Nature Conservancy, and the network of natural heritage programs and data centers. It is increasingly integrated with the IUCN Red List system and its categories for species include, presumed extinct, possibly extinct, critically imperiled, imperiled, vulnerable, apparently secure, and secure. The system also allows ambiguous or uncertain ranks including inexact numeric ranks, NatureServe adds a qualifier for captive or cultivated only, which has a similar meaning to the IUCN Red List extinct in the wild status. The Red Data Book of the Russian Federation is used within the Russian Federation, in Australia, the Environment Protection and Biodiversity Conservation Act 1999 describes lists of threatened species, ecological communities and threatening processes. The categories resemble those of the 1994 IUCN Red List Categories & Criteria, prior to the EPBC Act, a simpler classification system was used by the Endangered Species Protection Act 1992. Some state and territory governments also have their own systems for conservation status, in Belgium, the Flemish Research Institute for Nature and Forest publishes an online set of more than 150 nature indicators in Dutch. In Canada, the Committee on the Status of Endangered Wildlife in Canada is a group of experts that assesses and designates which wild species are in danger of disappearing from Canada. Under the Species at Risk Act, it is up to the federal government, in China, the State, provinces and some counties have determined their key protected wildlife species. There is the China red data book, in Finland, a large number of species are protected under the Nature Conservation Act, and through the EU Habitats Directive and EU Birds Directive. In Germany, the Federal Agency for Nature Conservation publishes red lists of endangered species, india has the Wild Life Protection Act,1972, Amended 2003 and the Biological Diversity Act,2002. In Japan, the Ministry of Environment publishes a Threatened Wildlife of Japan Red Data Book, in the Netherlands, the Dutch Ministry of Agriculture, Nature and Food Quality publishes a list of threatened species, and conservation is enforced by the Nature Conservation Act 1998. Species are also protected through the Wild Birds and Habitats Directives, in New Zealand, the Department of Conservation publishes the New Zealand Threat Classification System lists
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Vulnerable species
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Vulnerability is mainly caused by habitat loss or destruction of the species home. Vulnerable habitat or species are monitored and can become increasingly threatened, some species listed as vulnerable may be common in captivity, an example being the military macaw. There are currently 5196 animals and 6789 plants classified as vulnerable, compared with 1998 levels of 2815 and 3222, practices such as Cryoconservation of animal genetic resources have been enforced in efforts to conserve vulnerable breeds of livestock specifically. The International Union for Conservation of Nature uses several criteria to enter species in this category, a reduction of at least 20%, projected or suspected to be met within the next ten years or three generations, whichever is the longer, based on any of, or above. Population is characterised by a restriction in its area of occupancy or in the number of locations. E) Quantitative analysis showing the probability of extinction in the wild is at least 10% within 100 years
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IUCN Red List
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The IUCN Red List of Threatened Species, founded in 1964, is the worlds most comprehensive inventory of the global conservation status of biological species. The International Union for Conservation of Nature is the main authority on the conservation status of species. A series of Regional Red Lists are produced by countries or organizations, the IUCN Red List is set upon precise criteria to evaluate the extinction risk of thousands of species and subspecies. These criteria are relevant to all species and all regions of the world, the aim is to convey the urgency of conservation issues to the public and policy makers, as well as help the international community to try to reduce species extinction. Major species assessors include BirdLife International, the Institute of Zoology, the World Conservation Monitoring Centre, collectively, assessments by these organizations and groups account for nearly half the species on the Red List. The IUCN aims to have the category of every species re-evaluated every five years if possible, the 1964 IUCN Red List of Threatened Plants used the older pre-criteria Red List assessment system. Plants listed may not, therefore, appear in the current Red List, IUCN advise that is best to check both the online Red List and the 1997 plants Red List publication. The 2006 Red List, released on 4 May 2006 evaluated 40,168 species as a whole, plus an additional 2,160 subspecies, varieties, aquatic stocks, on 12 September 2007, the World Conservation Union released the 2007 IUCN Red List of Threatened Species. Russ Mittermeier, chief of Swiss-based IUCNs Primate Specialist Group, stated that 16,306 species are endangered with extinction,188 more than in 2006, the Red List includes the Sumatran orangutan in the Critically Endangered category and the Bornean orangutan in the Endangered category. The study shows at least 1,141 of the 5,487 mammals on Earth are known to be threatened with extinction, and 836 are listed as Data Deficient. The Red List of 2012 was released 19 July 2012 at Rio+20 Earth Summit, nearly 2,000 species were added, the IUCN assessed a total of 63,837 species which revealed 19,817 are threatened with extinction. With 3,947 described as endangered and 5,766 as endangered. At threat are 41% of amphibian species, 33% of reef-building corals, 30% of conifers, 25% of mammals, the IUCN Red List has listed 132 species of plants and animals from India as Critically Endangered. Extinct – No known individuals remaining, extinct in the wild – Known only to survive in captivity, or as a naturalized population outside its historic range. Critically endangered – Extremely high risk of extinction in the wild, Endangered – High risk of extinction in the wild. Vulnerable – High risk of endangerment in the wild, near threatened – Likely to become endangered in the near future. Does not qualify for a more at-risk category, widespread and abundant taxa are included in this category. Data deficient – Not enough data to make an assessment of its risk of extinction, Not evaluated – Has not yet been evaluated against the criteria
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Taxonomy (biology)
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Taxonomy is the science of defining groups of biological organisms on the basis of shared characteristics and giving names to those groups. The exact definition of taxonomy varies from source to source, but the core of the remains, the conception, naming. There is some disagreement as to whether biological nomenclature is considered a part of taxonomy, the broadest meaning of taxonomy is used here. The word taxonomy was introduced in 1813 by Candolle, in his Théorie élémentaire de la botanique, the term alpha taxonomy is primarily used today to refer to the discipline of finding, describing, and naming taxa, particularly species. In earlier literature, the term had a different meaning, referring to morphological taxonomy, ideals can, it may be said, never be completely realized. They have, however, a value of acting as permanent stimulants. Some of us please ourselves by thinking we are now groping in a beta taxonomy, turrill thus explicitly excludes from alpha taxonomy various areas of study that he includes within taxonomy as a whole, such as ecology, physiology, genetics, and cytology. He further excludes phylogenetic reconstruction from alpha taxonomy, thus, Ernst Mayr in 1968 defined beta taxonomy as the classification of ranks higher than species. This activity is what the term denotes, it is also referred to as beta taxonomy. How species should be defined in a group of organisms gives rise to practical and theoretical problems that are referred to as the species problem. The scientific work of deciding how to define species has been called microtaxonomy, by extension, macrotaxonomy is the study of groups at higher taxonomic ranks, from subgenus and above only, than species. While some descriptions of taxonomic history attempt to date taxonomy to ancient civilizations, earlier works were primarily descriptive, and focused on plants that were useful in agriculture or medicine. There are a number of stages in scientific thinking. Early taxonomy was based on criteria, the so-called artificial systems. Later came systems based on a complete consideration of the characteristics of taxa, referred to as natural systems, such as those of de Jussieu, de Candolle and Bentham. The publication of Charles Darwins Origin of Species led to new ways of thinking about classification based on evolutionary relationships and this was the concept of phyletic systems, from 1883 onwards. This approach was typified by those of Eichler and Engler, the advent of molecular genetics and statistical methodology allowed the creation of the modern era of phylogenetic systems based on cladistics, rather than morphology alone. Taxonomy has been called the worlds oldest profession, and naming and classifying our surroundings has likely been taking place as long as mankind has been able to communicate
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Animal
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Animals are multicellular, eukaryotic organisms of the kingdom Animalia. The animal kingdom emerged as a clade within Apoikozoa as the group to the choanoflagellates. Animals are motile, meaning they can move spontaneously and independently at some point in their lives and their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later in their lives. All animals are heterotrophs, they must ingest other organisms or their products for sustenance, most known animal phyla appeared in the fossil record as marine species during the Cambrian explosion, about 542 million years ago. Animals can be divided broadly into vertebrates and invertebrates, vertebrates have a backbone or spine, and amount to less than five percent of all described animal species. They include fish, amphibians, reptiles, birds and mammals, the remaining animals are the invertebrates, which lack a backbone. These include molluscs, arthropods, annelids, nematodes, flatworms, cnidarians, ctenophores, the study of animals is called zoology. The word animal comes from the Latin animalis, meaning having breath, the biological definition of the word refers to all members of the kingdom Animalia, encompassing creatures as diverse as sponges, jellyfish, insects, and humans. Aristotle divided the world between animals and plants, and this was followed by Carl Linnaeus, in the first hierarchical classification. In Linnaeuss original scheme, the animals were one of three kingdoms, divided into the classes of Vermes, Insecta, Pisces, Amphibia, Aves, and Mammalia. Since then the last four have all been subsumed into a single phylum, in 1874, Ernst Haeckel divided the animal kingdom into two subkingdoms, Metazoa and Protozoa. The protozoa were later moved to the kingdom Protista, leaving only the metazoa, thus Metazoa is now considered a synonym of Animalia. Animals have several characteristics that set apart from other living things. Animals are eukaryotic and multicellular, which separates them from bacteria and they are heterotrophic, generally digesting food in an internal chamber, which separates them from plants and algae. They are also distinguished from plants, algae, and fungi by lacking cell walls. All animals are motile, if only at life stages. In most animals, embryos pass through a stage, which is a characteristic exclusive to animals. With a few exceptions, most notably the sponges and Placozoa and these include muscles, which are able to contract and control locomotion, and nerve tissues, which send and process signals
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Chordate
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Chordates are deuterostomes, as during the embryo development stage the anus forms before the mouth. They are also bilaterally symmetric coelomates, in the case of vertebrate chordates, the notochord is usually replaced by a vertebral column during development, and they may have body plans organized via segmentation. There are also additional extinct taxa, the Vertebrata are sometimes considered as a subgroup of the clade Craniata, consisting of chordates with a skull, the Craniata and Tunicata compose the clade Olfactores. Of the more than 65,000 living species of chordates, the worlds largest and fastest animals, the blue whale and peregrine falcon respectively, are chordates, as are humans. Fossil chordates are known from at least as early as the Cambrian explosion, Hemichordata, which includes the acorn worms, has been presented as a fourth chordate subphylum, but it now is usually treated as a separate phylum. The Hemichordata, along with the Echinodermata, form the Ambulacraria, the Chordata and Ambulacraria form the superphylum Deuterostomia, composed of the deuterostomes. Attempts to work out the relationships of the chordates have produced several hypotheses. All of the earliest chordate fossils have found in the Early Cambrian Chengjiang fauna. Because the fossil record of early chordates is poor, only molecular phylogenetics offers a prospect of dating their emergence. However, the use of molecular phylogenetics for dating evolutionary transitions is controversial and it has also proved difficult to produce a detailed classification within the living chordates. Attempts to produce family trees shows that many of the traditional classes are paraphyletic. While this has been known since the 19th century, an insistence on only monophyletic taxa has resulted in vertebrate classification being in a state of flux. Although the name Chordata is attributed to William Bateson, it was already in prevalent use by 1880, ernst Haeckel described a taxon comprising tunicates, cephalochordates, and vertebrates in 1866. Though he used the German vernacular form, it is allowed under the ICZN code because of its subsequent latinization, among the vertebrate sub-group of chordates the notochord develops into the spine, and in wholly aquatic species this helps the animal to swim by flexing its tail. In fish and other vertebrates, this develops into the spinal cord, the pharynx is the part of the throat immediately behind the mouth. In fish, the slits are modified to form gills, a muscular tail that extends backwards behind the anus. This is a groove in the wall of the pharynx. In filter-feeding species it produces mucus to gather food particles, which helps in transporting food to the esophagus and it also stores iodine, and may be a precursor of the vertebrate thyroid gland
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Reptile
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Reptiles are tetrapod animals in the class Reptilia, comprising todays turtles, crocodilians, snakes, amphisbaenians, lizards, tuatara, and their extinct relatives. The study of these traditional reptile orders, historically combined with that of amphibians, is called herpetology. Because some reptiles are more related to birds than they are to other reptiles. For this reason, many scientists prefer to consider the birds part of Reptilia as well. Some early examples include the lizard-like Hylonomus and Casineria, in addition to the living reptiles, there are many diverse groups that are now extinct, in some cases due to mass extinction events. In particular, the K–Pg extinction wiped out the pterosaurs, plesiosaurs, ornithischians, and sauropods, as well as species of theropods, crocodyliforms. Modern non-avian reptiles inhabit every continent with the exception of Antarctica, several living subgroups are recognized, Testudines, approximately 400 species, Sphenodontia,1 species, Squamata, over 9,600 species, Crocodilia,25 species, and Aves,10,000 species. Reptiles are tetrapod vertebrates, creatures that either have four limbs or, unlike amphibians, reptiles do not have an aquatic larval stage. As amniotes, reptile eggs are surrounded by membranes for protection and transport, many of the viviparous species feed their fetuses through various forms of placenta analogous to those of mammals, with some providing initial care for their hatchlings. In the 18th century, the reptiles were, from the outset of classification, the terms reptile and amphibian were largely interchangeable, reptile being preferred by the French. Josephus Nicolaus Laurenti was the first to use the term Reptilia for an expanded selection of reptiles. Today, the two groups are commonly treated under the same heading as herptiles. He subsequently proposed the names of Sauropsida and Ichthyopsida for the two groups. In 1866, Haeckel demonstrated that vertebrates could be divided based on their strategies, and that reptiles, birds. The terms Sauropsida and Theropsida were used again in 1916 by E. S, Goodrich to distinguish between lizards, birds, and their relatives on the one hand and mammals and their extinct relatives on the other. Goodrich supported this division by the nature of the hearts and blood vessels in each group, according to Goodrich, both lineages evolved from an earlier stem group, Protosauria in which he included some animals today considered reptile-like amphibians, as well as early reptiles. Watson observed that the first two groups diverged very early in history, so he divided Goodrichs Protosauria between them. He also reinterpreted Sauropsida and Theropsida to exclude birds and mammals, thus his Sauropsida included Procolophonia, Eosuchia, Millerosauria, Chelonia, Squamata, Rhynchocephalia, Crocodilia, thecodonts, non-avian dinosaurs, pterosaurs, ichthyosaurs, and sauropterygians
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Turtle
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Turtles are reptiles of the order Testudines characterised by a special bony or cartilaginous shell developed from their ribs and acting as a shield. Turtle may refer to the order as a whole or to fresh-water, the order Testudines includes both extant and extinct species. The earliest known members of this date from 157 million years ago, making turtles one of the oldest reptile groups. Of the 327 known species alive today, some are highly endangered, turtles are ectotherms—animals commonly called cold-blooded—meaning that their internal temperature varies according to the ambient environment. However, because of their metabolic rate, leatherback sea turtles have a body temperature that is noticeably higher than that of the surrounding water. Turtles are classified as amniotes, along with reptiles, birds. Like other amniotes, turtles breathe air and do not lay eggs underwater, Chelonia is based on the Greek word χελώνη chelone tortoise, turtle, also denoting armor or interlocking shields, testudines, on the other hand, is based on the Latin word testudo tortoise. Turtle may either refer to the order as a whole, or to particular turtles that make up a form taxon that is not monophyletic, the meaning of the word turtle differs from region to region. In North America, all chelonians are commonly called turtles, including terrapins, in Great Britain, the word turtle is used for sea-dwelling species, but not for tortoises. The term tortoise usually refers to any land-dwelling, non-swimming chelonian, most land-dwelling chelonians are in the Testudinidae family, only one of the 14 extant turtle families. Terrapin is used to describe several species of small, edible, hard-shell turtles, typically found in brackish waters. Some languages do not have this distinction, as all of these are referred to by the same name, for example, in Spanish, the word tortuga is used for turtles, tortoises, and terrapins. A sea-dwelling turtle is tortuga marina, a freshwater species tortuga de río, the largest living chelonian is the leatherback sea turtle, which reaches a shell length of 200 cm and can reach a weight of over 900 kg. Freshwater turtles are generally smaller, but with the largest species, the Asian softshell turtle Pelochelys cantorii, a few individuals have been reported up to 200 cm. This dwarfs even the better-known alligator snapping turtle, the largest chelonian in North America and they became extinct at the same time as the appearance of man, and it is assumed humans hunted them for food. The only surviving giant tortoises are on the Seychelles and Galápagos Islands and can grow to over 130 cm in length, the largest ever chelonian was Archelon ischyros, a Late Cretaceous sea turtle known to have been up to 4.6 m long. The smallest turtle is the speckled padloper tortoise of South Africa and it measures no more than 8 cm in length and weighs about 140 g. Two other species of turtles are the American mud turtles
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Cryptodira
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Cryptodira is a suborder of Testudines that includes most living tortoises and turtles. Cryptodira differ from Pleurodira in that they lower their necks and pull the heads straight back into the shells and they include among their species freshwater turtles, snapping turtles, tortoises, soft-shell turtles, and sea turtles. Cryptodires evolved during the Jurassic period, and by the end of the Jurassic had almost completely replaced pleurodires in the lakes and rivers, meanwhile, pleurodires became the dominant freshwater testudines in the Cretaceous to Eocene of Europe, and produced a family of marine species, the Bothremydidae. The Cryptodira suborder has three living superfamilies, the Chelonioidea, Testudinoidea, and Trionychoidea, the families within the Kinosternoidea are now recognized as a paraphyletic assemblage of mostly primitive Trionychoidea, they do not form a natural group. Two circumscriptions of the Cryptodira are commonly found, one is used here, it includes a number of primitive extinct lineages known only from fossils, as well as the Eucryptodira. The alternate concept restricts the use of the term Cryptodira to the crown clade, the Cryptodira as understood here are called Cryptodiramorpha in this view. Under this approach, the pleurodires and cryptodires are not sister taxa, doi,10. 1086/275138 First page image Haaramo, Mikko, Mikkos Phylogeny Archive – Cryptodira. Rhodin, Anders G. J. van Dijk, Peter Paul, Inverson, turtles of the world,2011 update, Annotated checklist of taxonomy, synonymy, distribution and conservation status. Archived from the original on 2012-01-22, rhodin, Anders G. J. van Dijk, Peter Paul, Parham, James F. Turtles of the world,2008 checklist, archived from the original on 2012-04-23
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Dermochelyidae
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Dermochelyidae is a family of turtles which has seven extinct genera and one extant genus, including the largest living sea turtles. The following list of species was published by Hirayama and Tong in 2003. Van Dijk, Peter Paul, Inverson, John B, Turtles of the world,2011 update, Annotated checklist of taxonomy, synonymy, distribution and conservation status. Archived from the original on 2012-01-22, family Dermochelyidae from Turtles of the World by C. H
25.
Henri Marie Ducrotay de Blainville
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Henri Marie Ducrotay de Blainville was a French zoologist and anatomist. Blainville was born at Arques, near Dieppe, as a young man he went to Paris to study art, but ultimately devoted himself to natural history. He attracted the attention of Georges Cuvier, for whom he substituted as lecturer at the Collège de France and at the Athenaeum Club. In 1812 he was aided by Cuvier in acquiring the position of assistant professor of anatomy, eventually, relations between the two men soured, a situation that ended in open enmity. In 1825 Blainville was admitted a member of the French Academy of Sciences, two years later, on the death of Cuvier, he obtained the chair of comparative anatomy, of which he proved himself a worthy successor to his former teacher. In 1837, he was elected a member of the Royal Swedish Academy of Sciences. On May 1,1850, he died from an attack of apoplexy in a carriage at the Embarcadère du Havre in Paris. He was the authority of numerous zoological species, extinct and extant, including the eponymous Blainvilles beaked whale. He also described new species of reptiles. It was in 1822 that he coined the term paleontology, sur les ichthyolites, ou, Les poissons fossiles - On ichthyolites, or fossil fish. De lorganisation des animaux, ou Principes danatomie comparée - On the organization of animals, manuel de malacologie et de conchyliologie - Manual of malacology and conchology. Cours de physiologie générale et comparée - Course of general and comparative physiology, manuel dactinologie, ou de zoophytologie - Manual of actinology or zoophytology. Attribution This article incorporates text from a now in the public domain, Chisholm, Hugh, ed. Blainville
26.
Binomial nomenclature
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Such a name is called a binomial name, a binomen, binominal name or a scientific name, more informally it is also called a Latin name. The first part of the name identifies the genus to which the species belongs, for example, humans belong to the genus Homo and within this genus to the species Homo sapiens. The formal introduction of system of naming species is credited to Carl Linnaeus. But Gaspard Bauhin, in as early as 1623, had introduced in his book Pinax theatri botanici many names of genera that were adopted by Linnaeus. Although the general principles underlying binomial nomenclature are common to these two codes, there are differences, both in the terminology they use and in their precise rules. Similarly, both parts are italicized when a binomial name occurs in normal text, thus the binomial name of the annual phlox is now written as Phlox drummondii. In scientific works, the authority for a name is usually given, at least when it is first mentioned. In zoology Patella vulgata Linnaeus,1758, the original name given by Linnaeus was Fringilla domestica, the parentheses indicate that the species is now considered to belong in a different genus. The ICZN does not require that the name of the person who changed the genus be given, nor the date on which the change was made, in botany Amaranthus retroflexus L. – L. is the standard abbreviation used in botany for Linnaeus. – Linnaeus first named this bluebell species Scilla italica, Rothmaler transferred it to the genus Hyacinthoides, the ICN does not require that the dates of either publication be specified. Prior to the adoption of the binomial system of naming species. Together they formed a system of polynomial nomenclature and these names had two separate functions. First, to designate or label the species, and second, to be a diagnosis or description, such polynomial names may sometimes look like binomials, but are significantly different. For example, Gerards herbal describes various kinds of spiderwort, The first is called Phalangium ramosum, Branched Spiderwort, is aptly termed Phalangium Ephemerum Virginianum, Soon-Fading Spiderwort of Virginia. The Latin phrases are short descriptions, rather than identifying labels, the Bauhins, in particular Caspar Bauhin, took some important steps towards the binomial system, by pruning the Latin descriptions, in many cases to two words. The adoption by biologists of a system of binomial nomenclature is due to Swedish botanist and physician Carl von Linné. It was in his 1753 Species Plantarum that he first began using a one-word trivial name together with a generic name in a system of binomial nomenclature. This trivial name is what is now known as an epithet or specific name
27.
Domenico Vandelli
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Domenico Agostino Vandelli was an Italian naturalist, who did most of his scientific work in Portugal. He studied at the University of Padua, from which he received a doctorate in Natural Philosophy, while active as naturalist in Italy he began a correspondence with the Swedish naturalist Carl von Linné, which continued for several years. In 1763 he was invited by Catherine the Great of Russia to join the faculty of the University of St. Petersburg, in 1764 Vandelli moved to Portugal, where in 1765 he was appointed lecturer in chemistry and natural sciences at the University of Coimbra. He was the first supervisor for the orientation of the Botanical Garden of the University of Coimbra, one of his major works he published was the Tractatus de thermis agri patavini in 1761. In about 1793 he became the first director of the Botanical Gardens at the Palácio da Ajuda in Lisbon and he was one of the mentors of the Sciences Academy of Lisbon. In the field of herpetology he is best known for having described the worlds largest living turtle, Domenico Agostino Vandelli should not be confused with Domenico Vandelli, an Italian cartographer, scientist, and mathematician
28.
Synonym (taxonomy)
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For example, Linnaeus was the first to give a scientific name to the Norway spruce, which he called Pinus abies. This name is no longer in use, it is now a synonym of the current scientific name which is Picea abies, unlike synonyms in other contexts, in taxonomy a synonym is not interchangeable with the name of which it is a synonym. In taxonomy, synonyms are not equals, but have a different status, for any taxon with a particular circumscription, position, and rank, only one scientific name is considered to be the correct one at any given time. A synonym cannot exist in isolation, it is always an alternative to a different scientific name, given that the correct name of a taxon depends on the taxonomic viewpoint used a name that is one taxonomists synonym may be another taxonomists correct name. Synonyms may arise whenever the same taxon is described and named more than once, independently. They may also arise when existing taxa are changed, as when two taxa are joined to one, a species is moved to a different genus. To the general user of scientific names, in such as agriculture, horticulture, ecology, general science. A synonym is a name that was used as the correct scientific name but which has been displaced by another scientific name. Thus Oxford Dictionaries Online defines the term as a name which has the same application as another. In handbooks and general texts, it is useful to have mentioned as such after the current scientific name. Synonyms used in this way may not always meet the strict definitions of the synonym in the formal rules of nomenclature which govern scientific names. Changes of scientific name have two causes, they may be taxonomic or nomenclatural, a name change may be caused by changes in the circumscription, position or rank of a taxon, representing a change in taxonomic, scientific insight. A name change may be due to purely nomenclatural reasons, that is, based on the rules of nomenclature, the earliest such name is called the senior synonym, while the later name is the junior synonym. One basic principle of zoological nomenclature is that the earliest correctly published name, synonyms are important because if the earliest name cannot be used, then the next available junior synonym must be used for the taxon. Objective synonyms refer to taxa with the type and same rank. For example, John Edward Gray published the name Antilocapra anteflexa in 1855 for a species of pronghorn, however, it is now commonly accepted that his specimen was an unusual individual of the species Antilocapra americana published by George Ord in 1815. Ords name thus takes precedence, with Antilocapra anteflexa being a subjective synonym. Objective synonyms are common at the level of genera, because for various reasons two genera may contain the type species, these are objective synonyms
29.
Crocodilia
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The Crocodilia is an order of mostly large, predatory, semiaquatic reptiles, known as crocodilians. They first appeared 83.5 million years ago in the Late Cretaceous period and are the closest living relatives of birds, as the two groups are the only known survivors of the Archosauria. Members of the total group, the clade Pseudosuchia, appeared about 250 million years ago in the Early Triassic period. The order Crocodilia includes the true crocodiles, the alligators and caimans, although the term crocodiles is sometimes used to refer to all of these, crocodilians is a less ambiguous vernacular term for members of this group. Large, solidly built, lizard-like reptiles, crocodilians have flattened snouts, laterally compressed tails, and eyes, ears. They swim well and can move on land in a high walk and their skin is thick and covered in non-overlapping scales. They have conical, peg-like teeth and a powerful bite and they have a four-chambered heart and, somewhat like birds, a unidirectional looping system of airflow within the lungs, but like other non-avian reptiles they are ectotherms. Crocodilians are found mainly in lowlands in the tropics, but alligators also live in the southeastern United States, Crocodilians are typically solitary and territorial, though cooperative feeding does occur. During breeding, dominant males try to monopolise available females, females lay eggs in holes or in mounds and, unlike most other reptiles, care for their hatched young. Eight species of crocodilians are known to have attacked humans, the largest number of attacks comes from the Nile crocodile. Artistic and literary representations of crocodilians have appeared in cultures around the world since at least Ancient Egypt. Crocodilia and Crocodylia have been used interchangeably for decades starting with Schmidts redescription of the group from the defunct term Loricata. Schmidt used the older term Crocodilia, based on Owens original name for the group, shortly after, Wermuth opted for Crocodylia as the proper name for this redescribed group, basing it on the type genus Crocodylus. Dundee—in a revision of many reptilian and amphibian names—argued strongly for Crocodylia to be the spelling for the group, however, it was not until the advent of cladistics and phylogenetic nomenclature that a more solid justification for assuming one spelling over the other was proposed. Prior to 2003, Crocodilia/Crocodylia was a group that encompassed the modern-day animals as well as their distant relatives now in the larger groups called Crocodylomorpha. Under its current definition Crocodylia is restricted to only the most recent ancestor of todays modern-day crocodilians and this distinction is more important for paleontologists studying crocodilian evolution. As such, the alternate spellings Crocodilia and Crocodylia are still used interchangeably in the neontological literature, Crocodilia appears to be a Latinizing of the Greek κροκόδειλος, which means both lizard and Nile crocodile. Crocodylia, as coined by Wermuth, in regards to the genus Crocodylus appears to be derived from the ancient Greek κρόκη —meaning shingle or pebble—and δρîλος or δρεîλος for worm, the name may refer to the animals habit of basking on the pebbled shores of the Nile
30.
Species
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In biology, a species is the basic unit of biological classification and a taxonomic rank. A species is defined as the largest group of organisms in which two individuals can produce fertile offspring, typically by sexual reproduction. While this definition is often adequate, looked at more closely it is problematic, for example, with hybridisation, in a species complex of hundreds of similar microspecies, or in a ring species, the boundaries between closely related species become unclear. Other ways of defining species include similarity of DNA, morphology, all species are given a two-part name, a binomial. The first part of a binomial is the genus to which the species belongs, the second part is called the specific name or the specific epithet. For example, Boa constrictor is one of four species of the Boa genus, Species were seen from the time of Aristotle until the 18th century as fixed kinds that could be arranged in a hierarchy, the great chain of being. In the 19th century, biologists grasped that species could evolve given sufficient time, Charles Darwins 1859 book The Origin of Species explained how species could arise by natural selection. Genes can sometimes be exchanged between species by horizontal transfer, and species may become extinct for a variety of reasons. In his biology, Aristotle used the term γένος to mean a kind, such as a bird or fish, a kind was distinguished by its attributes, for instance, a bird has feathers, a beak, wings, a hard-shelled egg, and warm blood. A form was distinguished by being shared by all its members, Aristotle believed all kinds and forms to be distinct and unchanging. His approach remained influential until the Renaissance, when observers in the Early Modern period began to develop systems of organization for living things, they placed each kind of animal or plant into a context. Many of these early delineation schemes would now be considered whimsical, animals likewise that differ specifically preserve their distinct species permanently, one species never springs from the seed of another nor vice versa. In the 18th century, the Swedish scientist Carl Linnaeus classified organisms according to shared physical characteristics and he established the idea of a taxonomic hierarchy of classification based upon observable characteristics and intended to reflect natural relationships. At the time, however, it was widely believed that there was no organic connection between species, no matter how similar they appeared. However, whether or not it was supposed to be fixed, by the 19th century, naturalists understood that species could change form over time, and that the history of the planet provided enough time for major changes. Jean-Baptiste Lamarck, in his 1809 Zoological Philosophy, described the transmutation of species, proposing that a species could change over time, in 1859, Charles Darwin and Alfred Russel Wallace provided a compelling account of evolution and the formation of new species. Darwin argued that it was populations that evolved, not individuals and this required a new definition of species. Darwin concluded that species are what appear to be, ideas
31.
Sea turtle
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Sea turtles, sometimes called marine turtles, are reptiles of the order Testudines. The seven extant species of sea turtles are, the green, loggerhead, Kemps ridley, olive ridley, hawksbill, flatback, the majority of a sea turtles body is protected by its shell. The turtles shell is divided two sections, carapace and plastron. The shell is made up of plates called scutes. The leatherback is the sea turtle that does not have a hard shell. Instead, it bears a mosaic of bony plates beneath its leathery skin, in general, sea turtles have a more fusiform body plan than their terrestrial or freshwater counterparts. The reduced volume of a body means sea turtles can not retract their head, legs. However this more stream-line body plan reduces drag in the water, the leatherback is the largest species of sea turtle. Measuring 2-3 meters in length, and 1-1.5 m in width, other species are smaller, being mostly 60-120 cm and proportionally narrower. Sea turtles, along with turtles and tortoises, are part of the order Testudines. All species except the leatherback are in the family Cheloniidae, the leatherback is the only extant member of the family Dermochelyidae. The origin of sea turtles back to the Late Jurassic with genera such as Plesiochelys. In Africa, the first marine turtle is Angolachelys, from the Turonian of Angola, however, neither of these are related to extant sea turtles, the oldest representative of the lineage leading to these was Desmatochelys padillai, from the Early Cretaceous. A lineage of unrelated marine testudines, the pleurodire bothremydids, also survived well into the Cenozoic, Sea turtles constitute a single radiation that became distinct from all other turtles at least 110 million years ago. The flatback sea turtle is found solely on the northern coast of Australia, the Kemps ridley sea turtle is found solely in the Gulf of Mexico and along the East Coast of the United States. Sea turtles are found in the waters over continental shelves. During the first three to five years of life, sea turtles spend most of their time in the pelagic zone floating in seaweed mats, Green sea turtles in particular are often found in Sargassum mats, in which they find shelter and food. Once the sea turtle has reached adulthood it moves closer to the shore, females will come ashore to lay their eggs on sandy beaches during the nesting season
32.
Exoskeleton
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An exoskeleton is the external skeleton that supports and protects an animals body, in contrast to the internal skeleton of, for example, a human. In usage, some of the kinds of exoskeletons are known as shells. Examples of animals with exoskeletons include insects such as grasshoppers and cockroaches, the shells of certain sponges and the various groups of shelled molluscs, including those of snails, clams, tusk shells, chitons and nautilus, are also exoskeletons. Some animals, such as the tortoise, have both an endoskeleton and an exoskeleton, exoskeletons have a role in defense from pests and predators, support, and in providing an attachment framework for musculature. Exoskeletons contain chitin, the addition of calcium carbonate makes them harder and stronger, ingrowths of the arthropod exoskeleton known as apodemes serve as attachment sites for muscles. These structures are composed of chitin, and are six times as strong. Similar to tendons, apodemes can stretch to store energy for jumping. Many different species produce exoskeletons, which are composed of a range of materials, bone, cartilage, or dentine is used in the Ostracoderm fish and turtles. Chitin forms the exoskeleton in arthropods including insects, arachnids such as spiders, crustaceans such as crabs and lobsters, calcium carbonates constitute the shells of molluscs, brachiopods, and some tube-building polychaete worms. Silica forms the exoskeleton in the microscopic diatoms and radiolaria, one species of mollusc, the scaly-foot gastropod, even makes use of the iron sulfides greigite and pyrite. Some organisms, such as some foraminifera, agglutinate exoskeletons by sticking grains of sand, contrary to a common misconception, echinoderms do not possess an exoskeleton, as their test is always contained within a layer of living tissue. Exoskeletons have evolved many times,18 lineages evolved calcified exoskeletons alone. Further, other lineages have produced tough outer coatings analogous to an exoskeleton and this coating is constructed from bone in the armadillo, and hair in the pangolin. The armor of reptiles like turtles and Ankylosaurs is constructed of bone, crocodiles have bony scutes, since exoskeletons are rigid, they present some limits to growth. Organisms with open shells can grow by adding new material to the aperture of their shell, as is the case in snails, bivalves, a true exoskeleton, like that found in arthropods, must be shed when it is outgrown. A new exoskeleton is produced beneath the old one, as the old one is shed, the new skeleton is soft and pliable. The animal will pump itself up to expand the new shell to maximal size, when the shell has set, the empty space inside the new skeleton can be filled up as the animal eats. Failure to shed the exoskeleton once outgrown can result in the animal being suffocated within its own shell and this is the mechanism behind some insect pesticides, such as Azadirachtin
33.
Carapace
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A carapace is a dorsal section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron, in crustaceans, the carapace functions as a protective cover over the cephalothorax. Where it projects forward beyond the eyes, this projection is called a rostrum, the carapace is calcified to varying degrees in different crustaceans. Zooplankton within the phylum Crustacea also have a carapace and these include Cladocera, ostracods, and isopods, but isopods only have a developed cephalic shield carapace covering the head. In arachnids, the carapace is formed by the fusion of prosomal tergites into a plate which carries the eyes, ocularium, ozopores. In a few orders, such as Solifugae and Schizomida, the carapace may be subdivided, alternative terms for the carapace of arachnids and their relatives, which avoids confusion with crustaceans, are prosomal dorsal shield and peltidium. The carapace is the convex part of the shell structure of a turtle, consisting primarily of the animals rib cage, dermal armor
34.
Family (biology)
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In biological classification, family is one of the eight major taxonomic ranks, it is classified between order and genus. A family may be divided into subfamilies, which are intermediate ranks above the rank of genus. In vernacular usage, a family may be named one of its common members, for example, walnuts and hickory trees belong to the family Juglandaceae. What does or does not belong to a family—or whether a family should be recognized at all—are proposed and determined by practicing taxonomists. There are no rules for describing or recognizing a family. Taxonomists often take different positions about descriptions of taxa, and there may be no broad consensus across the community for some time. Some described taxa are accepted broadly and quickly, but others only rarely, if at all, the naming of families is codified by various international codes. In zoological nomenclature, the names of animals end with the suffix -idae. The concept of rank at time was not yet settled, and in the preface to the Prodromus Magnol spoke of uniting his families into larger genera. Carolus Linnaeus used the word familia in his Philosophia botanica to denote groups of plants, trees, herbs, ferns, palms. He used this term only in the section of the book. In zoology, the family as an intermediate between order and genus was introduced by Pierre André Latreille in his Précis des caractères génériques des insectes. He used families in some but not in all his orders of insects, families can be used for evolutionary, palaeontological and generic studies because they are more stable than lower taxonomic levels such as genera and species
35.
Ostia (Rome)
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Ostia is a large neighbourhood in the X Municipio of the commune of Rome, Italy, near the ancient port of Rome, named Ostia, which is now a major archaeological site known as Ostia Antica. Ostia is also the only municipio or district of Rome on the Tyrrhenian Sea, with about 85,000 inhabitants, Ostia is the first or second-most populated frazione of Italy, depending on whether Mestre is counted. The town is located on the Tyrrhenian coast, close to Acilia, the neighbourhood was founded in 1884 near the remains of Ostia Antica, the port city of ancient Rome. This was possible after reclamation of the marshland, which was infested by malaria. The first inhabitants were peasants coming from Ravenna, in Romagna, due to the opening of the urban Roma-Ostia railway in 1924, the new village soon became the favourite sea resort of the Romans, while many Art Nouveau houses were built on the waterfront. The new village was connected to central Rome through the new Via Ostiense, during the Fascist period, the government massively expanded the neighbourhood, which got its ultimate architectural character thanks to many new buildings in Stile Littorio. New infrastructures, like a road to Rome, the promenade. After World War II, many bathing establishments were built on the sea side, the new Cristoforo Colombo avenue connected Ostia with the EUR district in Rome. However, sea pollution, which became apparent during the 1970s, the building of the Leonardo da Vinci Airport in Fiumicino in 1956 made Ostia an attractive district for airport and airline workers. Italian intellectual, film director and poet Pier Paolo Pasolini was assassinated near the airport on 2 November 1975. In 1976 Ostia became part of the XIII Municipio of the Comune of Rome, nowadays, due to the expansion of the city, only the Park of Castelfusano separates Ostia from the other quarters of Rome. The regional Rome-Lido railway line, which carries over 90,000 passengers a day, connects Ostia to the centre of Rome, the full length of the line is 28.359 kilometres. It has 13 stops, and the time is roughly 37 minutes. The Roman terminal is at Roma Porta San Paolo station, very close to the Piramide stop, rail stops in Ostia are Ostia Antica, Ostia Lido Nord, Ostia Lido Centro, Ostia Stella Polare, Ostia Castel Fusano and Ostia Cristoforo Colombo. Ostia Online Site of the Centro Studi Storici Ambientali Ostia and of Genius Loci Publisher Le Date della storia di Ostia Met. Ro
36.
University of Padua
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The University of Padua is a premier Italian university located in the city of Padua, Italy. The University of Padua was founded in 1222 as a school of law and was one of the most prominent universities in early modern Europe and it is among the earliest universities of the world and the second oldest in Italy. The University of Padua is one of Italy’s leading universities and ranks in the first position in all the recent ranking of Italian large universities. In 2010 the university had approximately 65,000 students and in 2013 was ranked best university among Italian institutions of education with more than 40,000 students. The university is said to have been founded in 1222 when a large group of students. The first subjects to be taught were law and theology, there was also a Universitas Theologorum, established in 1373 by Urban V. The student body was divided into groups known as nations which reflected their places of origin, during this time, the university adopted the Latin motto, Universa universis patavina libertas. Nevertheless, the university had a turbulent history, and there was no teaching in 1237–61, 1509–17, the Botanical Garden of Padova, established by the university in 1545, was one of the oldest gardens of its kind in the world. Its title for oldest academic garden is in controversy because the Medici created one in Pisa in 1544, in addition to the garden, best visited in the spring and summer, the university also manages nine museums, including a History of physics museum. The University began teaching medicine in 1222 and it played a leading role in the identification and treatment of diseases and ailments, specializing in autopsies and the inner workings of the body. Since 1595, Paduas famous anatomical theatre drew artists and scientists studying the body during public dissections. It is the oldest surviving permanent anatomical theatre in Europe, anatomist Andreas Vesalius held the chair of Surgery and Anatomy and in 1543 published his anatomical discoveries in De Humani Corporis Fabrica. The book triggered public interest in dissections and caused many other European cities to establish anatomical theatres. On 25 June 1678, Elena Lucrezia Cornaro Piscopia, a Venetian noblewoman and mathematician, in recent years, the University has been able to meet the problems posed by overcrowded facilities by re-deploying over the Veneto as a whole. In 1990, the Institute of Management Engineering was set up in Vicenza, after which the courses at Brixen began once more. Other sites of re-deployment are at Rovigo, Treviso, Feltre, Castelfranco Veneto, Conegliano, Chioggia, recent changes in state legislation have also opened the way to greater autonomy for Italian universities, and in 1995 Padua adopted a new Statute that gave it greater independence. As the publications of innumerable conferences and congresses show, the modern-day University of Padua plays an important role in scholarly, notable people who have attended the University of Padua include, In natural sciences Nathaniel Eaton, Ph. D. and M. D
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Pope Clement XIII
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Pope Clement XIII, born Carlo della Torre di Rezzonico, was Pope from 6 July 1758 to his death in 1769. He was consecrated on 16 July 1758 and his pontificate was overshadowed by the constant pressure to suppress the Society of Jesus but despite this, he championed their order and also proved to be their greatest defender at that time. These efforts ultimately bore little fruition, born to Giovanni Battista Rezzonico and Vittoria Barbarigo, his brother was Aurelio. He received a Jesuit education in Bologna and later studied at the University of Padua where he obtained his doctorate in canon law, from there, he travelled to Rome where he attended the Pontifical Academy of Ecclesiastical Nobles. Rezzonico became the Referendary of the Apostolic Signatura and remained in position from 1716 to 1718 when he was appointed as the Governor of Fano. He was then ordained to the priesthood on 23 December 1731 in Rome, Pope Clement XII appointed him to the cardinalate in 1737 as the Cardinal-Deacon of San Nicola in Carcere and also filled various important posts in the Roman Curia. Rezzonico was chosen as Bishop of Padua in 1743 and he received consecration in Rome by Pope Benedict XIV himself. Rezzonico visited his diocese on frequent occasions and reformed the way that the diocese ran and he was the first to do this in five decades. He later opted to become the Cardinal-Priest of Santa Maria in Aracoeli in 1747, Pope Benedict XIV died of gout in 1758 and the College of Cardinals gathered at the papal conclave in order to elect a successor. Direct negotiations between the factions resulted in the proposal for the election of Rezzonico. On the evening of 6 July 1758, Rezzonico received 31 votes out of a possible 44 and he selected the pontifical name of Clement XIII in honor of Pope Clement XII, who elevated him to the cardinalate. Rezzonico was crowned as pontiff on 16 July 1758 by the protodeacon, in the same year, the Rezzonico family celebrated Ludovico Rezzonicos marriage into the powerful Savorgnan family. Rezzonico was notorious for his rampant nepotism throughout his pontificate, notwithstanding the meekness and affability of his upright and moderate character, he was modest to a fault and generous with his extensive private fortune. Clement XIIIs pontificate was repeatedly disturbed by disputes respecting the pressures to suppress the Jesuits coming from the progressive Enlightenment circles of the philosophes in France. Clement XIII placed the Encyclopédie of DAlembert and Diderot on the Index, more unexpected resistance came from the less progressive courts of Spain, the Two Sicilies, and Portugal. In 1758 the reforming minister of Joseph I of Portugal, the Marquis of Pombal, expelled the Jesuits from Portugal, in 1760, Pombal sent the papal nuncio home and recalled the Portuguese ambassador from the Vatican. Louis XVs ministers could not permit such an abrogation of French law, in Spain, they appeared to be safe, but Charles III of Spain, aware of the drawn-out contentions in Bourbon France, decided on a more peremptory efficiency. Much the same fate awaited them in the territories of the Bourbon Duke of Parma and Piacenza, in 1768, Clement XIII issued a strong protest against the policy of the Parmese government
38.
Zoology
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The term is derived from Ancient Greek ζῷον, zōion, i. e. animal and λόγος, logos, i. e. knowledge, study. The history of zoology traces the study of the kingdom from ancient to modern times. This ancient work was developed in the Middle Ages by Muslim physicians. During the Renaissance and early period, zoological thought was revolutionized in Europe by a renewed interest in empiricism. Microscopy revealed the unknown world of microorganisms, laying the groundwork for cell theory. The growing importance of natural theology, partly a response to the rise of mechanical philosophy, over the 18th and 19th centuries, zoology became an increasingly professional scientific discipline. Naturalists began to reject essentialism and consider the importance of extinction, cell theory provided a new perspective on the fundamental basis of life. These developments, as well as the results from embryology and paleontology, were synthesized in Charles Darwins theory of evolution by natural selection. In 1859, Darwin placed the theory of evolution on a new footing, by his discovery of a process by which organic evolution can occur. Darwin gave new direction to morphology and physiology, by uniting them in a biological theory. The end of the 19th century saw the fall of spontaneous generation, cell biology studies the structural and physiological properties of cells, including their behavior, interactions, and environment. This is done on both the microscopic and molecular levels, for single-celled organisms such as bacteria as well as the cells in multicellular organisms such as humans. Understanding the structure and function of cells is fundamental to all of the biological sciences, the similarities and differences between cell types are particularly relevant to molecular biology. Anatomy considers the forms of macroscopic structures such as organs and organ systems and it focuses on how organs and organ systems work together in the bodies of humans and animals, in addition to how they work independently. Anatomy and cell biology are two studies that are related, and can be categorized under structural studies. Physiology studies the mechanical, physical, and biochemical processes of living organisms by attempting to understand how all of the function as a whole. The theme of structure to function is central to biology, for example, what is learned about the physiology of yeast cells can also apply to human cells. The field of animal physiology extends the tools and methods of physiology to non-human species
39.
Leopold Fitzinger
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Leopold Joseph Franz Johann Fitzinger was an Austrian zoologist. Fitzinger was born in Vienna and studied botany at the University of Vienna under Nikolaus Joseph von Jacquin, later he became director of the zoos of Munich and Budapest. In 1826 he published Neue Classification der Reptilien, based partly on the work of his friends Friedrich Wilhelm Hemprich and Heinrich Boie, in 1843 he published Systema Reptilium, covering geckos, chameleons and iguanas
40.
Natural history
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Natural history is the research and study of organisms including animals, fungi and plants in their environment, leaning more towards observational than experimental methods of study. It encompasses scientific research but is not limited to it, with articles nowadays more often published in magazines than in academic journals. Grouped among the sciences, natural history is the systematic study of any category of natural objects or organisms. That is a broad designation in a world filled with many narrowly focused disciplines. For example, geobiology has a strong multi-disciplinary nature combining scientists, a person who studies natural history is known as a naturalist or natural historian. The English term natural history is a translation of the Latin historia naturalis and its meaning has narrowed progressively with time, while the meaning of the related term nature has widened. In antiquity, it covered essentially anything connected with nature or which used materials drawn from nature. For example, Pliny the Elders encyclopedia of this title, published circa 77 to 79 AD, covers astronomy, geography, man and his technology, medicine and superstition as well as animals and plants. Medieval European academics considered knowledge to have two divisions, the humanities and divinity, with science studied largely through texts rather than observation or experiment. In modern terms, natural philosophy roughly corresponded to modern physics and chemistry, natural history had been encouraged by practical motives, such as Linnaeus aspiration to improve the economic condition of Sweden. Similarly, the Industrial Revolution prompted the development of geology to help find useful mineral deposits, the astronomer, William Herschel was also a natural historian. Instead of working with plants or minerals he worked with the stars and he spent his time building telescopes to see the stars and the rest of the time watching the stars. In the beginning, he believed there to be a known as a nebulae. Herschel can be considered a natural historian because he observed the natural world, in the process he made charts of all the stars and kept records of all that he saw. S. Wilcove and T. Eisner, The close observation of organisms—their origins, their evolution, their behavior and it encompasses changes in internal states insofar as they pertain to what organisms do. Some definitions go further, focusing on observation of organisms in their environment. Bartholomew, A student of history, or a naturalist, studies the world by observing plants. A common thread in many definitions of natural history is the inclusion of a component, as seen in a recent definition by H. W. Greene
41.
Samuel Garman
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Samuel Walton Garman, or Garmann as he sometimes styled himself, was a naturalist/zoologist from Pennsylvania. He became noted as an ichthyologist and herpetologist, Garman was born in Indiana County, Pennsylvania, on 5 June 1843. In 1868 he joined an expedition to the American West with John Wesley Powell and he graduated from the Illinois State Normal University in 1870, and for the following year was principal of the Mississippi State Normal School. In 1871, he became professor of natural sciences in Ferry Hall Seminary, Lake Forest, Illinois, and he was a friend and regular correspondent of the naturalist Edward Drinker Cope, and in 1872 accompanied him on a fossil hunting trip to Wyoming. In 1873 he became assistant director of herpetology and ichthyology at Harvards Museum of Comparative Zoology and his work was mostly in the classification of fish, especially sharks, but also included reptiles and amphibians. Harvard College awarded him honorary degrees for his work, B. S. in 1898. While working at Harvard, he lived in Arlington Heights, Massachusetts, in 1895, he married Florence Armstrong of St. John, New Brunswick. On the reptiles and Batrachians of North America, on West Indian Iguanidae and on West Indian Scincidae. Cambridge, MA, Museum of Comparative Zoology at Harvard College, cambridge, MA, Museum of Comparative Zoology at Harvard College. Cambridge, MA, Museum of Comparative Zoology at Harvard College, cambridge, MA, Museum of Comparative Zoology at Harvard College. Cambridge, MA, Museum of Comparative Zoology at Harvard College, summers, Adam P. Koob, Thomas J. eds. A biographical sketch of Samuel Walton Garman, plagiostomia - the Sharks, Skates and Rays
42.
Mercury (mythology)
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Mercury is a major Roman god, being one of the Dii Consentes within the ancient Roman pantheon. He is the god of financial gain, commerce, eloquence, messages/communication, travelers, boundaries, luck, trickery and thieves. He was considered the son of Maia and Jupiter in Roman mythology, in his earliest forms, he appears to have been related to the Etruscan deity Turms, both gods share characteristics with the Greek god Hermes. He is often depicted holding the caduceus in his left hand, similar to his Greek equivalent he was awarded the caduceus by Apollo who handed him a magic wand, which later turned into the caduceus. Mercury did not appear among the di indigetes of early Roman religion. Rather, he subsumed the earlier Dei Lucrii as Roman religion was syncretized with Greek religion during the time of the Roman Republic, starting around the 4th century BC. He was often accompanied by a cockerel, herald of the new day, a ram or goat, symbolizing fertility, like Hermes, he was also a god of messages, eloquence and of trade, particularly of the grain trade. Mercury was also considered a god of abundance and commercial success, particularly in Gaul and he was also, like Hermes, the Romans psychopomp, leading newly deceased souls to the afterlife. Additionally, Ovid wrote that Mercury carried Morpheus dreams from the valley of Somnus to sleeping humans, archeological evidence from Pompeii suggests that Mercury was among the most popular of Roman gods. The god of commerce was depicted on two bronze coins of the Roman Republic, the Sextans and the Semuncia. This is probably because in the Roman syncretism, Mercury was equated with the Celtic god Lugus, Romans associated Mercury with the Germanic god Wotan, by interpretatio Romana, 1st-century Roman writer Tacitus identifies him as the chief god of the Germanic peoples. The Romans also made use of small statues of Mercury. Mercurius Arvernus, a syncretism of the Celtic Arvernus with Mercury, Mercurius Cimbrianus, a syncretism of Mercury with a god of the Cimbri sometimes thought to represent Odin. Mercurius Cissonius, a combination of Mercury with the Celtic god Cissonius, Mercurius Esibraeus, a syncretism of the Iberian deity Esibraeus with the Roman deity Mercury. Esibraeus is mentioned only in an inscription found at Medelim, Portugal, and is possibly the deity as Banda Isibraiegus. Mercurius Gebrinius, a syncretism of Mercury with the Celtic or Germanic Gebrinius, known from an inscription on an altar in Bonn, Mercurius Moccus, from a Celtic god, Moccus, who was equated with Mercury, known from evidence at Langres, France. The name Moccus implies that this deity was connected to boar-hunting, Mercurius Visucius, a syncretism of the Celtic god Visucius with the Roman god Mercury, attested in an inscription from Stuttgart, Germany. Visucius was worshiped primarily in the area of the empire in Gaul
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Cladistics
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Therefore, members of a group are assumed to share a common history and are considered to be closely related. The techniques and nomenclature of cladistics have been applied to other disciplines, Cladistics in the original sense refers to a particular set of methods used in phylogenetic analysis, although it is now sometimes used to refer to the whole field. What is now called the cladistic method appeared as early as 1901 with a work by Peter Chalmers Mitchell for birds and subsequently by Robert John Tillyard in 1921, Hennig referred to his own approach as phylogenetic systematics. Phenetics was championed at this time by the numerical taxonomists Peter Sneath and Robert Sokal, originally conceived, if only in essence, by Willi Hennig in a book published in 1950, cladistics did not flourish until its translation into English in 1966. Today, cladistics is the most popular method for constructing phylogenies from morphological, unlike phenetics, cladistics is specifically aimed at reconstructing evolutionary histories. The way for computational phylogenetics was paved by phenetics, a set of commonly used from the 1950s to 1980s. Phenetics did not try to reconstruct phylogenetic trees, rather, it tried to build dendrograms from similarity data, the cladistic method interprets each character state transformation implied by the distribution of shared character states among taxa as a potential piece of evidence for grouping. The outcome of an analysis is a cladogram – a tree-shaped diagram that is interpreted to represent the best hypothesis of phylogenetic relationships. Cladists contend that these models are unjustified, every cladogram is based on a particular dataset analyzed with a particular method. Different datasets and different methods, not to mention violations of the mentioned assumptions, only scientific investigation can show which is more likely to be correct. Since the cladograms provide competing accounts of events, at most one of them is correct. Within the primates, all anthropoids are hypothesized to have had a common ancestor all of whose descendants were anthropoids, the prosimians, on the other hand, form a paraphyletic taxon. When two or more taxa that are not nested within each other share a plesiomorphy, it is a symplesiomorphy, symplesiomorphies do not mean that the taxa that exhibit that character state are necessarily closely related. For example, Reptilia is traditionally characterized by being cold-blooded, whereas birds are warm-blooded, an apomorphy or derived state is an innovation. It can thus be used to diagnose a clade – or even to help define a clade name in phylogenetic nomenclature, features that are derived in individual taxa are called autapomorphies. Autapomorphies express nothing about relationships among groups, clades are identified by synapomorphies, for example, the possession of digits that are homologous with those of Homo sapiens is a synapomorphy within the vertebrates. The tetrapods can be singled out as consisting of the first vertebrate with such digits homologous to those of Homo sapiens together with all descendants of this vertebrate and it is therefore inferred to have evolved by convergence or reversal. Both mammals and birds are able to maintain a constant body temperature
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Protostegidae
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Protostegidae is a family of extinct marine turtles that lived during the Cretaceous period. The family includes some of the largest sea turtles that ever existed, the largest, Archelon, had a head a meter long. Like most sea turtles, they had flattened bodies and flippers for front appendages, as some of the first marine turtles, the protostegids set the general body plan for future species of sea turtles. They had a generally depressed turtle body plan, complete with four limbs, a tail. Like other sea turtles, they possessed oar-like front appendages especially evolved for swimming in the open ocean, similar to the still-extant, possibly closely related Dermochelyidae, protostegids possessed extremely reduced carapaces. Some specimens had skeletal protrusions from their ribs almost wrapping around their bodies in place of a complete shell, like modern sea turtles, protostegids had sharp beaks. One of the characteristics of the members of the family was their almost-disproportionately large heads. Specifically, some specimens of Archelon have been found with heads a meter long, in addition, the members of the family had somewhat reduced plastrons, as well. While all members of the family are extinct, palaeoecological studies on the members of the family have provided insight into the ecological roles of the Protostegidae. Analysis of fossil organs of some protostegids has revealed entire stomachs containing fossilized shellfish, the turtles, in turn, are postulated to have been preyed upon by the major predators of the time. Fossil protostegids have been found with tooth impressions from the large sharks of the time. Two specimens of Protostega gigas have been discovered to have tooth marks from large sharks, in addition, teeth of the extinct shark Cretoxyrhina mantelli have been found embedded in at least one Protostega skeleton. The latter species first appeared during the Early Cretaceous, as an early sea turtle, Santanachelys had several unspecialized characteristics, such as distinguishable digits in its flipper-like arms. Later relatives flippers were completely fused together for efficient swimming. As with most large fauna of the era, the Protostegidae died out during the events of the Cretaceous–Paleogene extinction event that led to the extinction of the dinosaurs, the exact phylogenetic position of protostegids among turtles is uncertain. Some phylogenetic studies determine the leatherback turtles in the family Dermochelyidae to be their closest living relatives, conversely, the phylogenetic analyses conducted by Joyce and Anquetin, which included one protostegid species, recovered the family as only distantly related to leatherback turtles. In 1888, the Belgian zoologist George Albert Boulenger published his classification of the Testudinata within the 9th edition of the Encyclopædia Britannica, the genus Protostega was placed within the family Sphargidae under the suborder Athecae. A year or so later, the entire suborder was downgraded by Karl Alfred von Zittel into a family within the Cryptodira, the unidentified specimen was fully described in 1998, as the species Santanachelys gaffneyi
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Fluid dynamics
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In physics and engineering, fluid dynamics is a subdiscipline of fluid mechanics that describes the flow of fluids. It has several subdisciplines, including aerodynamics and hydrodynamics, before the twentieth century, hydrodynamics was synonymous with fluid dynamics. This is still reflected in names of some fluid dynamics topics, like magnetohydrodynamics and hydrodynamic stability, the foundational axioms of fluid dynamics are the conservation laws, specifically, conservation of mass, conservation of linear momentum, and conservation of energy. These are based on mechanics and are modified in quantum mechanics. They are expressed using the Reynolds transport theorem, in addition to the above, fluids are assumed to obey the continuum assumption. Fluids are composed of molecules that collide with one another and solid objects, however, the continuum assumption assumes that fluids are continuous, rather than discrete. The fact that the fluid is made up of molecules is ignored. The unsimplified equations do not have a general solution, so they are primarily of use in Computational Fluid Dynamics. The equations can be simplified in a number of ways, all of which make them easier to solve, some of the simplifications allow some simple fluid dynamics problems to be solved in closed form. Three conservation laws are used to solve fluid dynamics problems, the conservation laws may be applied to a region of the flow called a control volume. A control volume is a volume in space through which fluid is assumed to flow. The integral formulations of the laws are used to describe the change of mass, momentum. Mass continuity, The rate of change of fluid mass inside a control volume must be equal to the net rate of flow into the volume. Mass flow into the system is accounted as positive, and since the vector to the surface is opposite the sense of flow into the system the term is negated. The first term on the right is the net rate at which momentum is convected into the volume, the second term on the right is the force due to pressure on the volumes surfaces. The first two terms on the right are negated since momentum entering the system is accounted as positive, the third term on the right is the net acceleration of the mass within the volume due to any body forces. Surface forces, such as forces, are represented by F surf. The following is the form of the momentum conservation equation
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Scute
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A scute or scutum is a bony external plate or scale overlaid with horn, as on the shell of a turtle, the skin of crocodilians, and the feet of birds. The term is used to describe the anterior portion of the mesonotum in insects. Scutes are similar to scales and serve the same function, unlike the scales of lizards and snakes, which are formed from the epidermis, scutes are formed in the lower vascular layer of the skin and the epidermal element is only the top surface. Forming in the dermis, the scutes produce a horny outer layer that is superficially similar to that of scales. Scutes will usually not overlap as snake scales, the outer keratin layer is shed piecemeal, and not in one continuous layer of skin as seen in snakes or lizards. The dermal base may contain bone and produce dermal armour, scutes with a bony base are properly called osteoderms. Dermal scutes are found in the feet of birds and tails of some mammals. The turtles shell is covered by scutes formed mostly of keratin and they are built similarly to horn, beak, or nail in other species. The tarsometatarsus and toes of most birds are covered in two types of scales, large scutes run along the dorsal side of the tarsometatarsus and toes, whereas smaller scutellae run along the sides. Unblocking the feather suppression program results in growing in place of scales along the tarsometatarsus. The bottoms of feet are covered in small, keeled scale-like structures known as reticulae. Evolutionary developmental studies on these structures have revealed that they are composed entirely of alpha keratin. In some species of Opiliones, fused abdominal segments are referred to as a scutum, osteoderms Scale Snake scales Keratin Skin Skeleton
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