Instruct: Given a question, retrieve documents that answer the question.
Query: When were the first Baryonyx fossils discovered?
In 1983, a relatively complete skeleton was excavated from the Smokejacks pit in Surrey, Engand. These remains were described by British paleontologists Alan J. Charig and Angela C. Milner in 1986 as the holotype of a new species, "Baryonyx walkeri." After the discovery of "Baryonyx," many new genera have since been described, the majority on very incomplete remains. However, other finds bear enough fossil material and distinct anatomical features to be assigned with confidence. Paul Sereno and colleagues described "Suchomimus" in 1998"," a baryonychine from Niger on the basis of a partial skeleton found in 1997. Later in 2004, partial jaw bones were recovered from the Alcântara Formation, these were referred to a new genus of spinosaurine named "Oxalaia" in 2011 by Alexander Kellner.
Excluding a few contested reports of much older forms from North America and India, the first complex multicellular life forms seem to have appeared at roughly 1500 Ma, in the Mesoproterozoic era of the Proterozoic eon. Fossil evidence from the later Ediacaran period of such complex life comes from the Lantian formation, at least 580 million years ago. 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 eon. By the middle of the following Cambrian period, a very diverse fauna is recorded in the Burgess Shale, including some which may represent stem groups of modern taxa. The increase in diversity of lifeforms during the early Cambrian is called the Cambrian explosion of life.
The first documented fossils to be recovered from the Bridger Formation were discovered on 11 August 1849 by Captain Howard Stansbury, who documented the discovery of fossilized shells and wood in his expedition report while scouting out the region for the United States Army Corps of Topographical Engineers. In the early-1860s, trapper Jack Robinson claimed to have discovered a number of sites along the base of the Uinta Mountains where grizzly bears had been turned to stone. When these claims were called into question by judge William A. Carter, Robinson brought Carter a bag filled with the fossils. One of the specimens recovered by Robinson was a well-preserved skull which resembled that of a grizzly bear. Judger Carter invited Louis Agassiz to observe the local strata, but Agassiz declined as the journey would have involved riding horseback to the site, a mode of transportation Agassiz abhorred. Carter's son-in-law, Dr. J. Van A. Carter, would go on to send a number of fossils to palaeontologist Joseph Leidy at the University of Pennsylvania in 1869. These fossils included the first Bridgerian fossil taxa, "Omomys carteri"; and the skull discovered by Robinson, which was described as "Palaeosyops paludosus". Another researcher responsible for sending off specimens was Dr. Joseph K. Corson, a close friend of Leidy's who hosted him and his family on two three to Fort Bridger in 1872, 1873, and 1879.
The museum's five rooms shows paleontological finds from the Besano area, including the "Besanosaurus", a type of ichthyosaur from the middle Triassic period.
The 6 meter "Besanosaurus leptorhynchus" discovered in 1993 is the biggest sea reptile fossil found in Italy, and was probably a pregnant female.
Since 2001 the museum has also housed the remains of a "Saltriosaurus", discovered in a quarry in Saltrio, which is the first big carnivorous dinosaur found in Lombardia.
Catopsbaatar is a genus of multituberculate, an extinct order of rodent-like mammals. It lived in what is now Mongolia during the late Campanian age of the Late Cretaceous Period, about 72 million years ago. The first fossils were collected in the early 1970s, and the animal was named as a new species of the genus "Djadochtatherium " in 1974, "D. catopsaloides". The specific name refers to the animal's similarity to the genus "Catopsalis". The species was moved to the genus "Catopsalis" in 1979, and received its own genus ("Catopsbaatar", Greek and Mongolian for "visible hero") in 1994. Five skulls, one molar, and one skeleton with a skull are known; the latter is the genus' most complete specimen. "Catopsbaatar" was a member of the family Djadochtatheriidae.
The first "Hylaeosaurus" fossils were discovered in West Sussex. On 20 July 1832, fossil collector Gideon Mantell wrote to Professor Benjamin Silliman that when a gunpowder explosion had demolished a quarry rock face in Tilgate Forest, several of the boulders freed showed the bones of a saurian. A local fossil dealer had assembled the about fifty pieces, described by him as a "great consarn of bites and boanes". Having doubts about the value of the fragments, Mantell had nevertheless purchased the pieces and soon discovered they could be united into a single skeleton, partially articulated. Mantell was delighted with the find because previous specimens of "Megalosaurus" and "Iguanodon" had consisted of single bone elements. The discovery in fact represented the most complete non-avian dinosaur skeleton known at the time. He was strongly inclined to describe the find as belonging to the latter genus, but during a visit by William Clift, the curator of the Royal College of Surgeons of England museum, and his assistant John Edward Gray, he began to doubt the identification. Clift was the first to point out that several plates and spikes were probably part of a body armour, attached to the back or sides of the rump. In November 1832 Mantell decided to create a new generic name: "Hylaeosaurus". It is derived from the Greek ὑλαῖος, "hylaios", "of the wood". Mantell originally claimed the name "Hylaeosaurus" meant "forest lizard", after the Tilgate Forest in which it was discovered. Later, he claimed that it meant "Wealden lizard" ("wealden" being another word for "forest"), in reference to the Wealden Group, the name for the early Cretaceous geological formation in which the dinosaur was first found.
Three specimens have been assigned to "Sinosauropteryx prima": the holotype GMV 2123 (and its counter slab [opposite face], NIGP 127586), NIGP 127587, and D 2141. Another specimen, IVPP V14202, was assigned to the genus but not to the only species by Zhang and colleagues. The assignment of an additional larger specimen to "S. prima", GMV 2124, was later found to be in error. All of the fossils were found in the Jianshangou or Dawangzhangzi Beds of the Yixian Formation in the Beipiao and Lingyuan regions of Liaoning, China. These fossil beds have been dated to 124.6–122 million years ago, during the early Aptian stage of the Early Cretaceous.
The first publicized discovery of a partial fossil mosasaur skull in 1764 by quarry workers in a subterranean gallery of a limestone quarry in Mount Saint Peter, near the Dutch city of Maastricht, preceded any major dinosaur fossil discoveries, but remained little known. However, a second find of a partial skull drew the Age of Enlightenment's attention to the existence of fossilized animals that were different from any known living creatures. When the specimen was discovered between 1770 and 1774, Johann Leonard Hoffmann, a surgeon and fossil collector, corresponded about it with the most influential scientists of his day, making the fossil famous. The original owner, though, was Godding, a canon of Maastricht cathedral.
Dimetrodon ( or , meaning "two measures of teeth") is an extinct genus of synapsids that lived during the Cisuralian (Early Permian), around 295–272 million years ago (Ma). It is a member of the family Sphenacodontidae. The most prominent feature of "Dimetrodon" is the large neural spine sail on its back formed by elongated spines extending from the vertebrae. It walked on four legs and had a tall, curved skull with large teeth of different sizes set along the jaws. Most fossils have been found in the southwestern United States, the majority coming from a geological deposit called the Red Beds of Texas and Oklahoma. More recently, fossils have been found in Germany. Over a dozen species have been named since the genus was first described in 1878.
The fossilized remains of "Homo sapiens idaltu" were discovered at Herto Bouri near the Middle Awash site of Ethiopia's Afar Triangle in 1997 by Tim White, but were first unveiled in 2003. Herto Bouri is a region of Ethiopia under volcanic layers. According to radioisotope dating, the layers are between 154,000 and 160,000 years old. Three well preserved crania are accounted for, the best preserved being from an adult male (BOU-VP-16/1) having a brain capacity of . The other crania include another partial adult male and a six-year-old child.
"Pteranodon" was the first pterosaur found outside of Europe. Its fossils first were found by Othniel Charles Marsh in 1870, in the Late Cretaceous Smoky Hill Chalk deposits of western Kansas. These chalk beds were deposited at the bottom of what was once the Western Interior Seaway, a large shallow sea over what now is the midsection of the North American continent. These first specimens, YPM 1160 and YPM 1161, consisted of partial wing bones, as well as a tooth from the prehistoric fish "Xiphactinus", which Marsh mistakenly believed to belong to this new pterosaur (all known pterosaurs up to that point had teeth). In 1871, Marsh named the find ""Pterodactylus oweni"", assigning it to the well-known (but much smaller) European genus "Pterodactylus". Marsh also collected more wing bones of the large pterosaur in 1871. Realizing that the name he had chosen had already been used for Harry Seeley's European pterosaur species "Pterodactylus oweni" in 1864, Marsh re-named his giant North American pterosaur Pterodactylus occidentalis, meaning "Western wing finger," in his 1872 description of the new specimen. He also named two additional species, based on size differences: Pterodactylus ingens (the largest specimen so far), and Pterodactylus velox (the smallest).
Recent molecular phylogenetic studies suggest that most placental orders diverged late in the Cretaceous period, about 100 to 85 million years ago, but that modern families first appeared later, in the late Eocene and early Miocene epochs of the Cenozoic period. Fossil-based analyses, on the contrary, limit the placentals to the Cenozoic. Many Cretaceous fossil sites contain well-preserved lizards, salamanders, birds, and mammals, but not the modern forms of mammals. It is likely that they simply did not exist, and that the molecular clock runs fast during major evolutionary radiations. On the other hand, there is fossil evidence from of hoofed mammals that may be ancestors of modern ungulates.
Because fossils identifiable as "P. sternbergi" are found exclusively in the lower layers of the Niobrara Formation, and "P. longiceps" fossils exclusively in the upper layers, a fossil lacking the skull can be identified based on its position in the geologic column (though for many early fossil finds, precise data about its location was not recorded, rendering many fossils unidentifiable).
Marc Boada discovered, in the late 1990s, a new fossil-bearing locality from the village of Basturs. As the village already lent its name to a locality where dinosaur eggs had been found, it was named the Basturs Poble (BP) locality, "poble" derived from the word for village. The locality belongs to the Conques Formation of the Tremp Group, dated to the late-Early Maastrictian. Over ten years, from 2001 through 2011, field work was done at this site, and a massive bonebed - consisting of some one thousand skeletal elements - was discovered. The discovery was first reported in the literature in an abstract at the "55th Symposium for Vertebrate Palaeontology and Comparative Anatomy and the 16th meeting of the Symposium for Palaeontological Preparation and Conservation" conference in 2007. The authors, then, approached the bonebed under the hypothesis of a single species being present at the site. It was reported that all ontogenetic stages were present. Later, a poster presentation and abstract at another conference suggested the specimens may have belonged to "Koutalisaurus kohlororum", but they cautioned an adult dentary from the bonebed would need to be discovered to test the hypothesis. This was later rejected, as "Koutalisaurus" was found to be an invalid "nomen dubium". In 2018, the material was instead noted as possibly referrable to "Pararhabdodon isonensis".
Sinosauropteryx (meaning "Chinese reptilian wing", ) is a compsognathid dinosaur. Described in 1996, it was the first dinosaur taxon outside of Avialae (birds and their immediate relatives) to be found with evidence of feathers. It was covered with a coat of very simple filament-like feathers. Structures that indicate colouration have also been preserved in some of its feathers, which makes "Sinosauropteryx" the first non-avialian dinosaurs where colouration has been determined. The colouration includes a reddish and light banded tail. Some contention has arisen with an alternative interpretation of the filamentous impression as remains of collagen fibres, but this has not been widely accepted.
The team discovered the remains of the largest dinosaur to walk in the southern parts of Africa , namely a 190-million-year-old fossilised egg of a Massospondylus dinosaur. This dinosaur lived in the Late Triassic and Early Jurassic, a period from about 230-million years ago to about 185-million years ago. The Massospondylus wandered about in great herds, migrating back and forth between what would millions of years later become Southern Africa and Russia, when the southern super-continent, Gondwana, was still intact. The rocks that were laid down during this period are called the Stormberg Group of rocks, and it is in rocks of the Stormberg Group that the fossils of Massospondylus and other dinosaurs were found. Massospondylus dinosaurs hatched from eggs not much larger than a hen’s egg, but grew into big creatures 5 to 6 metres long. They had large bodies, long necks and small heads, and long tails.
Edward Tyson is regarded as the founder of modern comparative anatomy. He is credited with determining that whales and dolphins are, in fact, mammals. Also, he concluded that chimpanzees are more similar to humans than to monkeys because of their arms. Marco Aurelio Severino also compared various animals, including birds, in his "Zootomia democritaea", one of the first works of comparative anatomy. In the 18th and 19th century, great anatomists like George Cuvier, Richard Owen and Thomas Henry Huxley revolutionized our understanding of the basic build and systematics of vertebrates, laying the foundation for Charles Darwin's work on evolution. An example of a 20th-century comparative anatomist is Victor Negus, who worked on the structure and evolution of the larynx. Until the advent of genetic techniques like DNA sequencing, comparative anatomy together with embryology were the primary tools for understanding phylogeny, as exemplified by the work of Alfred Romer.
220,000,000 BC, Late Triassic (Arizona) − This episode follows the evolution of the first dinosaurs and other prehistoric creatures in the late Triassic period.152,000,000 BC, Late Jurassic (Colorado) − This episode follows the story of a young female "Diplodocus" and her brothers and sisters in the late Jurassic period.149,000,000 BC, Late Jurassic (Oxfordshire) − This episode follows the life of several baby "Ophthalmosaurus" and a bull "Liopleurodon" in the late Jurassic period.127,000,000 BC, Early Cretaceous (Brazil) − This episode follows a male "Ornithocheirus" on his long journey to the mating grounds in the early Cretaceous period.106,000,000 BC, Early Cretaceous (Antarctica) − This episode follows the hardships of an Antarctican "Leaellynasaura" clan in the early Cretaceous period.65,500,000 BC, Late Cretaceous (Montana) − This episode follows the final years of the dinosaurs and a mother "Tyrannosaurus rex" and her babies in the late Cretaceous period.49,000,000 BC, Early Eocene (Germany) − This episode follows the life of a mother "Leptictidium" and her babies in the dense forests of Germany in the early Eocene epoch.36,000,000 BC, Late Eocene (Pakistan) − This episode follows the sea journey of a pregnant female "Basilosaurus" search for food in the late Eocene epoch.25,000,000 BC, Late Oligocene (Mongolia) − This episode follows the life of a young "Paraceratherium" and his mother from his birth in the late Oligocene epoch.3,200,000 BC, Late Pliocene (Ethiopia) − This episode follows the hardships of an "Australopithecus" group and a young called Blue in the late Pliocene epoch.1,000,000 BC, Early Pleistocene (Paraguay) − This episode follows a male "Smilodon" called Half-Tooth after he lost his territory in the early Pleistocene epoch.30,000 BC, Late Pleistocene (North Sea, Belgium, and Swiss Alps) − This episode follows a herd of woolly mammoth journey to the Alps in the last Ice Age of the late Pleistocene epoch.This episode details a list of animals from the first season that the developers thought were the most impressive creatures on Earth.
In the hall representing the Cretaceous period, which is the last period of the Mesozoic era from 145 to 66 million years ago, the displays relate to the biological and social habits of dinosaurs, reasons for their extinction by the end of the Cretaceous period, that are attributed to meteorite, volcanic eruptions and intense geographic and climatic changes. Evolution of birds inferred as theropods evolving from the non-avian dinosaurs are represented by the "Archaeopteryx" (a prehistoric bird) and dinosaurs such as the "Deinonychus" or the "Dromaeosaurus".
While the first "Pteranodon" wing bones were collected by Marsh and Cope in the early 1870s, the first "Pteranodon" skull was found on May 2, 1876, along the Smoky Hill River in Wallace County (now Logan County), Kansas, USA, by Samuel Wendell Williston, a fossil collector working for Marsh. A second, smaller skull soon was discovered as well. These skulls showed that the North American pterosaurs were different from any European species, in that they lacked teeth and had bony crests on their skulls. Marsh recognized this major difference, describing the specimens as "distinguished from all previously known genera of the order Pterosauria by the entire absence of teeth." Marsh recognized that this characteristic warranted a new genus, and he coined the name "Pteranodon" ("wing without tooth") in 1876. Marsh reclassified all the previously named North American species from "Pterodactylus" to "Pteranodon". He considered the smaller skull to belong to "Pteranodon occidentalis", based on its size. Marsh classified the larger skull, YPM 1117, in the new species "Pteranodon longiceps", which he thought to be a medium-sized species in between the small "P. occidentalis" and the large "P. ingens". Marsh also named several additional species: Pteranodon comptus and "Pteranodon nanus" were named for fragmentary skeletons of small individuals, while "Pteranodon gracilis" was based on a wing bone that he mistook for a pelvic bone. He soon realized his mistake, and re-classified that specimen again into a separate genus, which he named "Nyctosaurus". "P, nanus" was also later recognized as a "Nyctosaurus" specimen.
The Morrison Formation is a sequence of shallow marine and alluvial sediments which, according to radiometric dating, ranges between 156.3 million years old (Ma) at its base, to 146.8 million years old at the top, which places it in the late Oxfordian, Kimmeridgian, and early Tithonian stages of the Late Jurassic period. This formation is interpreted as a semiarid environment with distinct wet and dry seasons. The Morrison Basin where dinosaurs lived, stretched from New Mexico to Alberta and Saskatchewan, and was formed when the precursors to the Front Range of the Rocky Mountains started pushing up to the west. The deposits from their east-facing drainage basins were carried by streams and rivers and deposited in swampy lowlands, lakes, river channels and floodplains. This formation is similar in age to the Solnhofen Limestone Formation in Germany and the Tendaguru Formation in Tanzania. In 1877 this formation became the center of the Bone Wars, a fossil-collecting rivalry between early paleontologists Othniel Charles Marsh and Edward Drinker Cope.
Baryonychines have been found in Africa, with "Suchomimus" and "Cristatusaurus," as well as in Europe, with "Baryonyx" and "Suchosaurus". "Baryonyx-"like teeth are also reported from the Ashdown Sands of Sussex, in England, and the Burgos Province, in Spain. A partial skeleton and many fossil teeth indicate spinosaurids were widespread in Asia. As of 2012, three have been named: "Ichthyovenator," "Siamosaurus" and ""Sinopliosaurus" fusuiensis". In 2014, a spinosaurid tooth was discovered in Malaysia; the first dinosaur remains discovered in the country. At la Cantalera-1, a site in the Early Barremanian Blesa Formation in Treul, Spain, two types of spinosaurid teeth were found, and they were assigned, tentatively, as indeterminate spinosaurine and baryonychine taxa. An intermediate spinosaurid was discovered in the Early Cretaceous Eumeralla Formation, Australia. It is known from a single 4 cm long partial cervical vertebra, designated NMV P221081. It is missing most of the neural arch. The specimen is from a juvenile estimated to be about 2 to 3 meters long (6–9 ft). Out of all spinosaurs it most closely resembles "Baryonyx".
In 1997, Charig and Milner noted that two fragmentary spinosaurid snouts from the Elrhaz Formation of Niger (reported by the French palaeontologist Philippe Taquet in 1984) were similar enough to "Baryonyx" that they considered them to belong to an indeterminate species of the genus (despite their much younger Aptian geological age). In 1998, these fossils became the basis of the genus and species "Cristatusaurus lapparenti", named by Taquet and the American palaeontologist Dale Russell. The American palaeontologist Paul Sereno and colleagues named the new genus and species "Suchomimus tenerensis" later in 1998, based on more complete fossils from the Elrhaz Formation. In 2002, the German palaeontologist Hans-Dieter Sues and colleagues proposed that "Suchomimus tenerensis" was similar enough to "Baryonyx walkeri" to be considered a species within the same genus (as "B. tenerensis"), and that "Suchomimus" was identical to "Cristatusaurus". Milner concurred that the material from Niger was indistinguishable from "Baryonyx" in 2003. In a 2004 conference abstract, Hutt and Newberry supported the synonymy based on a large theropod vertebra from the Isle of Wight which they attributed to an animal closely related to "Baryonyx" and "Suchomimus". Later studies have kept "Baryonyx" and "Suchomimus" separate, whereas "Cristatusaurus" has been proposed to be either a "nomen dubium" or possibly distinct from both. A 2017 review paper by the Brazilian palaeontologist Carlos Roberto A. Candeiro and colleagues stated that this debate was more in the realm of semantics than science, as it is generally agreed that "B. walkeri" and "S. tenerensis" are distinct, related species.
The first spinosaurid fossil, a single conical tooth, was discovered circa 1820 by British paleontologist Gideon Mantell in the Wadhurst Clay Formation. In 1841 Sir Richard Owen mistakenly assigned it to a crocodilian he named "Suchosaurus" ("crocodile lizard"), a second species, "S. girardi", was later named in 1897. However, the spinosaurid nature of "Suchosaurus" was not recognized until a 1998 redescription of "Baryonyx."
In 2003, Milner noted that some teeth at the Natural History Museum previously identified as belonging to the genera "Suchosaurus" and "Megalosaurus" probably belonged to "Baryonyx". The type species of "Suchosaurus", "S. cultridens", was named by the British biologist Richard Owen in 1841, based on teeth discovered by the British geologist Gideon A. Mantell in Tilgate Forest, Sussex. Owen originally thought the teeth to have belonged to a crocodile; he was yet to name the group Dinosauria, which happened the following year. A second species, "S. girardi", was named by the French palaeontologist Henri Émile Sauvage in 1897, based on jaw fragments and a tooth from Boca do Chapim, Portugal. In 2007, the French palaeontologist Éric Buffetaut considered the teeth of "S. girardi" very similar to those of "Baryonyx" (and "S. cultridens") except for the stronger development of the tooth crown flutes (or "ribs"; lengthwise ridges), suggesting that the remains belonged to the same genus. Buffetaut agreed with Milner that the teeth of "S. cultridens" were almost identical to those of "B. walkeri", but with a ribbier surface. The former taxon might be a senior synonym of the latter (since it was published first), depending on whether the differences were within a taxon or between different ones. According to Buffetaut, since the holotype specimen of "S. cultridens" is a single tooth and that of "B. walkeri" is a skeleton, it would be more practical to retain the newer name. In 2011, Mateus and colleagues agreed that "Suchosaurus" was closely related to "Baryonyx", but considered both species in the former genus "nomina dubia" (dubious names) since their holotype specimens were not considered diagnostic (lacking distinguishing features) and could not be definitely equated with other taxa. In any case, the identification of "Suchosaurus" as a spinosaurid makes it the first named member of the family.