London is the capital and largest city of both England and the United Kingdom. Standing on the River Thames in the south-east of England, at the head of its 50-mile estuary leading to the North Sea, London has been a major settlement for two millennia. Londinium was founded by the Romans; the City of London, London's ancient core − an area of just 1.12 square miles and colloquially known as the Square Mile − retains boundaries that follow its medieval limits. The City of Westminster is an Inner London borough holding city status. Greater London is governed by the Mayor of the London Assembly. London is considered to be one of the world's most important global cities and has been termed the world's most powerful, most desirable, most influential, most visited, most expensive, sustainable, most investment friendly, most popular for work, the most vegetarian friendly city in the world. London exerts a considerable impact upon the arts, education, fashion, healthcare, professional services and development, tourism and transportation.
London ranks 26 out of 300 major cities for economic performance. It is one of the largest financial centres and has either the fifth or sixth largest metropolitan area GDP, it is the most-visited city as measured by international arrivals and has the busiest city airport system as measured by passenger traffic. It is the leading investment destination, hosting more international retailers and ultra high-net-worth individuals than any other city. London's universities form the largest concentration of higher education institutes in Europe. In 2012, London became the first city to have hosted three modern Summer Olympic Games. London has a diverse range of people and cultures, more than 300 languages are spoken in the region, its estimated mid-2016 municipal population was 8,787,892, the most populous of any city in the European Union and accounting for 13.4% of the UK population. London's urban area is the second most populous in the EU, after Paris, with 9,787,426 inhabitants at the 2011 census.
The population within the London commuter belt is the most populous in the EU with 14,040,163 inhabitants in 2016. London was the world's most populous city from c. 1831 to 1925. London contains four World Heritage Sites: the Tower of London. Other landmarks include Buckingham Palace, the London Eye, Piccadilly Circus, St Paul's Cathedral, Tower Bridge, Trafalgar Square and The Shard. London has numerous museums, galleries and sporting events; these include the British Museum, National Gallery, Natural History Museum, Tate Modern, British Library and West End theatres. The London Underground is the oldest underground railway network in the world. "London" is an ancient name, attested in the first century AD in the Latinised form Londinium. Over the years, the name has attracted many mythicising explanations; the earliest attested appears in Geoffrey of Monmouth's Historia Regum Britanniae, written around 1136. This had it that the name originated from a supposed King Lud, who had taken over the city and named it Kaerlud.
Modern scientific analyses of the name must account for the origins of the different forms found in early sources Latin, Old English, Welsh, with reference to the known developments over time of sounds in those different languages. It is agreed; this was adapted into Latin as Londinium and borrowed into Old English, the ancestor-language of English. The toponymy of the Common Brythonic form is much debated. A prominent explanation was Richard Coates's 1998 argument that the name derived from pre-Celtic Old European *lowonida, meaning "river too wide to ford". Coates suggested that this was a name given to the part of the River Thames which flows through London. However, most work has accepted a Celtic origin for the name, recent studies have favoured an explanation along the lines of a Celtic derivative of a proto-Indo-European root *lendh-, combined with the Celtic suffix *-injo- or *-onjo-. Peter Schrijver has suggested, on these grounds, that the name meant'place that floods'; until 1889, the name "London" applied to the City of London, but since it has referred to the County of London and Greater London.
"London" is sometimes written informally as "LDN". In 1993, the remains of a Bronze Age bridge were found on the south foreshore, upstream of Vauxhall Bridge; this bridge either reached a now lost island in it. Two of those timbers were radiocarbon dated to between 1750 BC and 1285 BC. In 2010 the foundations of a large timber structure, dated to between 4800 BC and 4500 BC, were found on the Thames's south foreshore, downstream of Vauxhall Bridge; the function of the mesolithic structure is not known. Both structures are on the south bank. Although there is evidence of scattered Brythonic settlements in the area, the first major settlement was founded by the Romans about four years after the invasion
Pterodaustro is a genus of Cretaceous pterodactyloid pterosaur from South America, which lived 105 million years ago. The first fossils, among them the holotype PLV 2571, a thigh bone, were in the late sixties discovered by Bonaparte in the Lagarcito Formation, situated in the San Luis Province of Argentina, dating from the Albian; the genus has also been found in Chile in the Santa Ana Formation. At the Argentine site, the just 50 square metres large "Loma del Pterodaustro", since during several expeditions over 750 Pterodaustro specimens have been collected, 288 of them having been catalogued until 2008; this makes the species one of the best known pterosaurs, with examples from all growth stages, from egg to adult. The genus was named in 1969 by José Bonaparte as an as yet undescribed nomen nudum; the first description followed in 1970, making the name valid, the type species being Pterodaustro guiñazui. The genus name is derived from Greek pteron, "wing" and Latin auster, "south"; the elements are combined as a condensed pteron de austro, "wing from the south".
The specific name honours paleontologist Román Guiñazú. It was emended in 1978 by Peter Wellnhofer into guinazui, because diacritical signs such as the tilde are not allowed in species names. Pterodaustro has a elongated skull, up to 29 centimetres long; the portion in front of the eye sockets comprises 85% of skull length. The long snout and lower jaws curve upwards. Pterodaustro has about a thousand bristle-like modified teeth in its lower jaws that might have been used to strain crustaceans, plankton and other small creatures from the water; these teeth stand for the most part not in separate alveoli but in two long grooves parallel to the edges of the jaw. They have a length of three centimetres and are oval in cross-section, with a width of just 0.2–0.3 millimetres. At first it was suspected these structures were not true teeth at all, but research established they were built like normal teeth, including enamel, dentine and a pulp. Despite being made of hard material, they might still have been flexible to some extent due to their extreme length-width ratio, a bend of up to 45° being possible.
The upper jaws carried teeth, but these were small with a flat conical base and a spatula-formed crown. These teeth do not have separate tooth sockets but were held by ligaments in a special tooth pad, covered with small ossicles, or bone plates; the back of the skull was rather elongated and in a low position. Pterodaustro had an adult wingspan of 250 centimetres, its hindlimbs are rather robust and its feet large. Its tail is uniquely elongated for a pterodactyloid, containing 22 caudal vertebrae, whereas other members of this group have at most sixteen. Pterodaustro strained food with its tooth comb, a method called "filter feeding" practised by modern flamingos. Once it caught its food, Pterodaustro mashed it with the small, globular teeth present in its upper jaw. Like other ctenochasmatoids, Pterodaustro has a long torso and proportionally massive and splayed hindfeet, adaptations for swimming. Robert Bakker suggested. At least two specimens of Pterodaustro have been found, MIC V263 and MIC V243, with gizzard stones in the stomach cavity, the first reported for any pterosaur.
These clusters of small stones with angled edges support the idea that Pterodaustro ate small, hard-shelled aquatic crustaceans using filter-feeding. Such invertebrates are abundant in the sediment of the fossil site. A study of the growth stages of Pterodaustro concluded that juveniles grew fast in their first two years, attaining about half of the adult size, they reached sexual maturity, growing at a slower rate for four to five years until there was a determinate growth stop. In 2004 a Pterodaustro embryo in an egg was reported, specimen MHIN-UNSL-GEO-V246; the egg was elongated, six centimetres long and 22 millimetres across and its flexible shell was covered with a thin layer, 0.3 mm thick, of calcite. Three-dimensionally preserved eggs were reported in 2014. Comparisons between the scleral rings of Pterodaustro and modern birds and reptiles suggest that it may have been nocturnal and similar in activity patterns to modern anseriform birds that feed at night; because of its long torso and neck and comparatively short legs, Pterodaustro was unique among pterosaurs in having difficulties to launch.
With the pterosaurian quadrupedal launching mechanism, it would have required frantic and fairly-low angled take-offs possible only in open areas, much like modern geese and swans. Bonaparte in 1970 assigned Pterodaustro to the Pterodactylidae. However, from 1996 cladistic studies by Alexander Kellner and David Unwin have shown a position in the Ctenochasmatidae, together with other filter feeders; the genus Puntanipterus might be a subjective junior synonym of Pterodaustro. Cladogram following Andres, Clark & Xu, 2014. List of pterosaur genera Timeline of pterosaur research Giants of the Mesozoic: Pterodaustro
A heronry, sometimes called a heron rookery, is a breeding ground for herons. Although their breeding territories are on more protected small islands in lakes or retention ponds, herons breed in heronries; some of the notable heronries are: Kaggaladu Heronry is in Karnataka state of India. This heronry, in the Tumkur district of Karnataka, was first made known to the outside world in 1999 by members of the Tumkur-based NGO Wildlife Aware Nature Club. Cleeve Heronry, in a woodland near the village of Cleeve in North Somerset, UK. Hilgay Heronry is in Norfolk, it is situated in a small copse on the edge of The Fens in the UK. An average of c. 40 pairs of grey heron nests each year at this site, in ash and European larch trees. The Florida Everglades in south Florida, of the United States. Thousands of birds, including herons, egrets and storks, nest in mangroves. Bird colony
Corvidae is a cosmopolitan family of oscine passerine birds that contains the crows, rooks, jays, treepies and nutcrackers. In common English, they are known as the crow family, or, more technically, corvids. Over 120 species are described; the genus Corvus, including the jackdaws, crows and ravens, makes up over a third of the entire family. Corvids display remarkable intelligence for animals of their size and are among the most intelligent birds thus far studied. Members of the family have demonstrated self-awareness in mirror tests and tool-making ability, skills which until were thought to be possessed only by humans and a few other higher mammals, their total brain-to-body mass ratio is equal to that of non-human great apes and cetaceans, only lower than that of humans. They are medium to large in size, with strong feet and bills, rictal bristles, a single moult each year. Corvids are found worldwide except for the tip of the polar ice caps; the majority of the species are found in tropical South and Central America, southern Asia and Eurasia, with fewer than 10 species each in Africa and Australasia.
The genus Corvus has re-entered Australia in recent geological prehistory, with five species and one subspecies there. Several species of raven have reached oceanic islands, some of these species are now threatened with extinction or have become extinct; the family Corvidae was introduced by the English zoologist William Elford Leach in a guide to the contents of the British Museum published in 1820. Over the years, much disagreement has arisen on the exact evolutionary relationships of the corvid family and their relatives. What seemed clear was that corvids are derived from Australasian ancestors and from there spread throughout the world. Other lineages derived from these ancestors evolved into ecologically diverse, but Australasian groups. In the late 1970s and throughout the 1980s, Sibley and Ahlquist united the corvids with other taxa in the Corvida, based on DNA–DNA hybridization; the presumed corvid relatives included currawongs, birds of paradise, quail-thrushes, monarch flycatchers and drongos, shrikes and vangas, but current research favors the theory that this grouping is artificial.
The corvids constitute the core group of the Corvoidea, together with their closest relatives. They are the core group of the Corvida, which includes the related groups, such as Old World orioles and vireos. Clarification of the interrelationships of the corvids has been achieved based on cladistic analysis of several DNA sequences; the jays and magpies do not constitute monophyletic lineages, but rather seem to split up into an American and Old World lineage, an Holarctic and Oriental lineage, respectively. These are not related among each other; the position of the azure-winged magpie, which has always been a major enigma, is less clear than before. The crested jay is traditionally included in the Corvidae, but might not be a true member of this family being closer to the helmetshrikes or shrikes; the Hume's ground "jay" is in fact a member of the tit family Paridae. The following tree represents current insights in the phylogeny of the Crow family according to J. Boyd; the earliest corvid fossils date to the mid-Miocene, about 17 million years ago.
The known prehistoric corvid genera appear to be of the New World and Old World jay and Holarctic magpie lineages: Miocorvus Miopica Miocitta Corvidae gen. et sp. indet. Protocitta Corvidae gen. et sp. indet. - belongs in an extant genus Henocitta In addition, there are numerous fossil species of extant genera since the Mio–Pliocene European Corvus. Corvids are large to large passerines with a robust build, strong legs and all species except the pinyon jay have nostrils covered by bristle-like feathers. Many corvids of temperate zones have black or blue coloured plumage; the sexes are similar in color and size. Corvids have stout bills and large wingspans; the family includes the largest members of the passerine order. The smallest corvid is the dwarf jay, at 21.5 cm. The largest corvids are the common raven and the thick-billed raven, both of which exceed 1,400 grams and 65 cm. Species can be identified based on size and geography. Corvids occur in most climatic zones. Most do not migrate significantly.
However, during a shortage of food, eruptive migration can occur. When species are migratory, they will form large flocks in the travel south. One reason for the success of crows, compared to ravens, is their ability to overlap breeding territory. During breeding season, cr
Sauropoda, or the sauropods, are a clade of saurischian dinosaurs. They had long necks, long tails, small heads, four thick, pillar-like legs, they are notable for the enormous sizes attained by some species, the group includes the largest animals to have lived on land. Well-known genera include Brachiosaurus, Diplodocus and Brontosaurus. Sauropods first appeared in the late Triassic Period, where they somewhat resembled the related group "Prosauropoda". By the Late Jurassic, sauropods had become widespread. By the Late Cretaceous, those groups had been replaced by the titanosaurs, which had a near-global distribution. However, as with all other non-avian dinosaurs alive at the time, the titanosaurs died out in the Cretaceous–Paleogene extinction event. Fossilised remains of sauropods have been found on every continent, including Antarctica; the name Sauropoda was coined by O. C. Marsh in 1878, is derived from Greek, meaning "lizard foot". Sauropods are one of the most recognizable groups of dinosaurs, have become a fixture in popular culture due to their large sizes.
Complete sauropod fossil finds are rare. Many species the largest, are known only from isolated and disarticulated bones. Many near-complete specimens lack tail tips and limbs. Sauropods were herbivorous quite long-necked quadrupeds with spatulate teeth, they had tiny heads, massive bodies, most had long tails. Their hind legs were thick and powerful, ending in club-like feet with five toes, though only the inner three bore claws, their forelimbs were rather more slender and ended in pillar-like hands built for supporting weight. Many illustrations of sauropods in the flesh miss these facts, inaccurately depicting sauropods with hooves capping the claw-less digits of the feet, or more than three claws or hooves on the hands; the proximal caudal vertebrae are diagnostic for sauropods. The sauropods' most defining characteristic was their size; the dwarf sauropods were counted among the largest animals in their ecosystem. Their only real competitors in terms of size are the rorquals, such as the blue whale.
But, unlike whales, sauropods were terrestrial animals. Their body structure did not vary as much as other dinosaurs due to size constraints, but they displayed ample variety. Some, like the diplodocids, possessed tremendously long tails, which they may have been able to crack like a whip as a signal or to deter or injure predators, or to make sonic booms. Supersaurus, at 33 to 34 metres long, was the longest sauropod known from reasonably complete remains, but others, like the old record holder, were extremely long; the holotype vertebra of Amphicoelias fragillimus may have come from an animal 58 metres long. However, a research published in 2015 speculated that the size estimates of A. fragillimus may have been exaggerated. The longest dinosaur known from reasonable fossils material is Argentinosaurus huinculensis with length estimates of 25 metres to 39.7 metres. The longest terrestrial animal alive today, the reticulated python, only reaches lengths of 6.95 metres. Others, like the brachiosaurids, were tall, with high shoulders and long necks.
Sauroposeidon was the tallest, reaching about 18 metres high, with the previous record for longest neck being held by Mamenchisaurus. By comparison, the giraffe, the tallest of all living land animals, is only 4.8 to 5.5 metres tall. The best evidence indicates that the most massive were Argentinosaurus, Alamosaurus, Antarctosaurus. There was poor evidence that so-called Bruhathkayosaurus, might have weighed over 175 metric tons but this has been questioned; the weight of Amphicoelias fragillimus was estimated at 122.4 metric tons but 2015 research argued that these estimates may have been exaggerated. The largest land animal alive today, the Savannah elephant, weighs no more than 10.4 metric tons. Among the smallest sauropods were the primitive Ohmdenosaurus, the dwarf titanosaur Magyarosaurus, the dwarf brachiosaurid Europasaurus, 6.2 meters long as a fully-grown adult. Its small stature was the result of insular dwarfism occurring in a population of sauropods isolated on an island of the late Jurassic in what is now the Langenberg area of northern Germany.
The diplodocoid sauropod Brachytrachelopan was the shortest member of its group because of its unusually short neck. Unlike other sauropods, whose necks could grow to up to four times the length of their backs, the neck of Brachytrachelopan was shorter than its backbone. On or shortly before 29 March 2017 a sauropod footprint about 5.6 feet long was found at Walmadany in the Kimberley Region of Western Australia. The report said; as massive quadrupeds, sauropods developed specialized graviportal limbs. The hind feet were broad, retained three claws in most species. Unusual compared with other animals were the modified front feet; the front feet of sauropods were dissimilar from those of modern
Mammals are vertebrate animals constituting the class Mammalia, characterized by the presence of mammary glands which in females produce milk for feeding their young, a neocortex, fur or hair, three middle ear bones. These characteristics distinguish them from reptiles and birds, from which they diverged in the late Triassic, 201–227 million years ago. There are around 5,450 species of mammals; the largest orders are the rodents and Soricomorpha. The next three are the Primates, the Cetartiodactyla, the Carnivora. In cladistics, which reflect evolution, mammals are classified as endothermic amniotes, they are the only living Synapsida. The early synapsid mammalian ancestors were sphenacodont pelycosaurs, a group that produced the non-mammalian Dimetrodon. At the end of the Carboniferous period around 300 million years ago, this group diverged from the sauropsid line that led to today's reptiles and birds; the line following the stem group Sphenacodontia split off several diverse groups of non-mammalian synapsids—sometimes referred to as mammal-like reptiles—before giving rise to the proto-mammals in the early Mesozoic era.
The modern mammalian orders arose in the Paleogene and Neogene periods of the Cenozoic era, after the extinction of non-avian dinosaurs, have been among the dominant terrestrial animal groups from 66 million years ago to the present. The basic body type is quadruped, most mammals use their four extremities for terrestrial locomotion. Mammals range in size from the 30–40 mm bumblebee bat to the 30-meter blue whale—the largest animal on the planet. Maximum lifespan varies from two years for the shrew to 211 years for the bowhead whale. All modern mammals give birth to live young, except the five species of monotremes, which are egg-laying mammals; the most species-rich group of mammals, the cohort called placentals, have a placenta, which enables the feeding of the fetus during gestation. Most mammals are intelligent, with some possessing large brains, self-awareness, tool use. Mammals can communicate and vocalize in several different ways, including the production of ultrasound, scent-marking, alarm signals and echolocation.
Mammals can organize themselves into fission-fusion societies and hierarchies—but can be solitary and territorial. Most mammals are polygynous. Domestication of many types of mammals by humans played a major role in the Neolithic revolution, resulted in farming replacing hunting and gathering as the primary source of food for humans; this led to a major restructuring of human societies from nomadic to sedentary, with more co-operation among larger and larger groups, the development of the first civilizations. Domesticated mammals provided, continue to provide, power for transport and agriculture, as well as food and leather. Mammals are hunted and raced for sport, are used as model organisms in science. Mammals have been depicted in art since Palaeolithic times, appear in literature, film and religion. Decline in numbers and extinction of many mammals is driven by human poaching and habitat destruction deforestation. Mammal classification has been through several iterations since Carl Linnaeus defined the class.
No classification system is universally accepted. George Gaylord Simpson's "Principles of Classification and a Classification of Mammals" provides systematics of mammal origins and relationships that were universally taught until the end of the 20th century. Since Simpson's classification, the paleontological record has been recalibrated, the intervening years have seen much debate and progress concerning the theoretical underpinnings of systematization itself through the new concept of cladistics. Though field work made Simpson's classification outdated, it remains the closest thing to an official classification of mammals. Most mammals, including the six most species-rich orders, belong to the placental group; the three largest orders in numbers of species are Rodentia: mice, porcupines, beavers and other gnawing mammals. The next three biggest orders, depending on the biological classification scheme used, are the Primates including the apes and lemurs. According to Mammal Species of the World, 5,416 species were identified in 2006.
These were grouped into 153 families and 29 orders. In 2008, the International Union for Conservation of Nature completed a five-year Global Mammal Assessment for its IUCN Red List, which counted 5,488 species. According to a research published in the Journal of Mammalogy in 2018, the number of recognized mammal species is 6,495 species included 96 extinct; the word "mammal" is modern, from the scientific name Mammalia coined by Carl Linnaeus in 1758, derived from the Latin mamma. In an influential 1988 paper, Timothy Rowe defined Mammalia phylogenetically as the crown group of mammals, the clade consisting of the most recent common ancestor of living monotremes and therian m
Pterosaurs were flying reptiles of the extinct clade or order Pterosauria. They existed during most of the Mesozoic: from the late Triassic to the end of the Cretaceous. Pterosaurs are the earliest vertebrates known to have evolved powered flight, their wings were formed by a membrane of skin and other tissues stretching from the ankles to a lengthened fourth finger. Early species had long toothed jaws and long tails, while forms had a reduced tail, some lacked teeth. Many sported furry coats made up of hair-like filaments known as pycnofibers, which covered their bodies and parts of their wings. Pterosaurs spanned a wide range of adult sizes, from the small anurognathids to the largest known flying creatures of all time, including Quetzalcoatlus and Hatzegopteryx. Pterosaurs are referred to in the popular media and by the general public as "flying dinosaurs", but the term "dinosaur" is restricted to just those reptiles descended from the last common ancestor of the groups Saurischia and Ornithischia, current scientific consensus is that this group excludes the pterosaurs, as well as the various groups of extinct marine reptiles, such as ichthyosaurs and mosasaurs.
Unlike these other reptiles, pterosaurs are nonetheless more related to birds and dinosaurs than to crocodiles or any other living reptile. Pterosaurs are colloquially referred to as pterodactyls in fiction and by journalists. However, pterodactyl only refers to members of the genus Pterodactylus, more broadly to members of the suborder Pterodactyloidea of the pterosaurs; the anatomy of pterosaurs was modified from their reptilian ancestors by the adaption to flight. Pterosaur bones were air-filled, like the bones of birds, they had a keeled breastbone, developed for the attachment of flight muscles and an enlarged brain that shows specialised features associated with flight. In some pterosaurs, the backbone over the shoulders fused into a structure known as a notarium, which served to stiffen the torso during flight, provide a stable support for the shoulder blade. Pterosaur wings were formed by membranes of skin and other tissues; the primary membranes attached to the long fourth finger of each arm and extended along the sides of the body to the ankles.
While thought of as simple leathery structures composed of skin, research has since shown that the wing membranes of pterosaurs were complex dynamic structures suited to an active style of flight. The outer wings were strengthened by spaced fibers called actinofibrils; the actinofibrils themselves consisted of three distinct layers in the wing, forming a crisscross pattern when superimposed on one another. The function of the actinofibrils is unknown. Depending on their exact composition, they may have been stiffening or strengthening agents in the outer part of the wing; the wing membranes contained a thin layer of muscle, fibrous tissue, a unique, complex circulatory system of looping blood vessels. As shown by cavities in the wing bones of larger species and soft tissue preserved in at least one specimen, some pterosaurs extended their system of respiratory air sacs into the wing membrane; the pterosaur wing membrane is divided into three basic units. The first, called the propatagium, was the forward-most part of the wing and attached between the wrist and shoulder, creating the "leading edge" during flight.
This membrane may have incorporated the first three fingers of the hand, as evidenced in some specimens. The brachiopatagium was the primary component of the wing, stretching from the elongated fourth finger of the hand to the hind limbs. At least some pterosaur groups had a membrane that stretched between the legs connecting to or incorporating the tail, called the uropatagium, it is agreed though that non-pterodactyloid pterosaurs had a broader uro/cruropatagium, with pterodactyloids only having membranes running along the legs. A bone unique to pterosaurs, known as the pteroid, connected to the wrist and helped to support a forward membrane between the wrist and shoulder. Evidence of webbing between the three free fingers of the pterosaur forelimb suggests that this forward membrane may have been more extensive than the simple pteroid-to-shoulder connection traditionally depicted in life restorations; the position of the pteroid bone itself has been controversial. Some scientists, notably Matthew Wilkinson, have argued that the pteroid pointed forward, extending the forward membrane.
This view was contradicted in a 2007 paper by Chris Bennett, who showed that the pteroid did not articulate as thought and could not have pointed forward, but rather inward toward the body as traditionally thought. Peters proposed that the pteroid articulated with the ‘saddle' of the radiale and both the pteroid and preaxial carpal were migrated centralia; this view of the articulation of the pteroid has since been supported by specimens of Changchengopterus pani and Darwinopterus linglongtaensis, both of which show the pteroid in articulation with the proximal syncarpal. The pterosaur