Instruct: Given a question, retrieve passages that answer the question.
Query: Where were the first Baryonyx fossils found?
Baryonyx () is a genus of theropod dinosaur which lived in the Barremian stage of the Early Cretaceous Period, about 130–125 million years ago. The first skeleton was discovered in 1983 in the Weald Clay Formation of Surrey, England, and became the holotype specimen of B. walkeri, named by palaeontologists Alan J. Charig and Angela C. Milner in 1986. The generic name, "Baryonyx", means "heavy claw" and alludes to the animal's very large claw on the first finger; the specific name, "walkeri", refers to its discoverer, amateur fossil collector William J. Walker. The holotype specimen is one of the most complete theropod skeletons from the UK (and remains the most complete spinosaurid), and its discovery attracted media attention. Specimens later discovered in other parts of the United Kingdom and Iberia have also been assigned to the genus.
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).
"Sinosauropteryx" lived in what is now northeastern China during the early Cretaceous period. It was among the first dinosaurs discovered from the Yixian Formation in Liaoning Province, and was a member of the Jehol Biota. Well-preserved fossils of this species illustrate many aspects of its biology, such as its diet and reproduction.
During the upper Triassic period, about 210 million years ago, the region around Frick was a dry lowland with flat hills and small depressions. During the rainy season, the depressions filled with water and dinosaurs congregated around the ponds. When they died, their bodies were covered by the mud in the ponds and fossilized, creating rich fossil beds in Frick. The first Plateosaurus fossils were discovered in 1961 and further excavations during the following decades have discovered numerous fossils. In 2006, the only Coelophysoidea (a small flesh-eating dinosaur species) fossil in Switzerland, was found by an amateur paleontologist in Frick.
Among the first scientists to explore the Muirkirk Deposit was Maryland state geologist Phillip Thomas Tyson. He brought some of the strange bones discovered in the iron mines to a meeting of the Maryland Academy of Sciences in 1859, where his colleagues identified them as dinosaurs. Paleontologist Othniel Charles Marsh was also interested in Maryland fossils. In the winter of 1887, he sent John Bell Hatcher to search the iron mines. Hatcher recovered hundreds of fossils, including the remains of ancient turtles and crocodiles. In the 1890s, Smithsonian Institution scientists Charles Gilmore and Arthur Bibbins also visited Prince George's County, uncovering dinosaur teeth and other fossils that were added to the Smithsonian collection.
Ichthyosaur fossils of the species "Shonisaurus popularis" were first discovered in the area in 1928. Excavations were conducted through the 1960s, and the remains of approximately 40 ichthyosaurs were found. Until 2004, these remains included the largest ichthyosaurs ever discovered. Several specimens were left where they were found, and can be viewed by the public. These specimens are protected from the elements by a large barn. The fossils are about a 10-minute drive from the Berlin ghost town. The ichthyosaur fossils were designated a National Natural Landmark in 1973.
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.
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".
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 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.
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 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.
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.
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 "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.
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.
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.
"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).
Dubois's complete collection of fossils were transferred between 1895 and 1900 to what is now known as the Naturalis, in Leiden in the Netherlands. The main fossil of Java Man, the skullcap cataloged as "Trinil 2", has been dated biostratigraphically, that is, by correlating it with a group of fossilized animals (a "faunal assemblage") found nearby on the same geological horizon, which is itself compared with assemblages from other layers and classified chronologically. Ralph von Koenigswald first assigned Java Man to the Trinil Fauna, a faunal assemblage that he composed from several Javanese sites. He concluded that the skullcap was about 700,000 years old, thus dating from the beginning of the Middle Pleistocene.
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.
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".
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".
Direct fossil evidence shows that spinosaurids fed on fish as well as a variety of other small to medium-sized animals, including dinosaurs. "Baryonyx" was found with scales of the prehistoric fish "Scheenstia" in its body cavity, and these were abraded, hypothetically by gastric juices. Bones of a young "Iguanodon", also abraded, were found alongside this specimen. If these represent "Baryonyx"’s meal, the animal was, whether in this case a hunter, or a scavenger, an eater of more diverse fare than fish. Moreover, there is a documented example of a spinosaurid having eaten a pterosaur, as one "Irritator" tooth was found embedded within the fossil vertebrae of an ornithocheirid pterosaur found in the Romualdo Formation of Brazil. This may represent a predation or a scavenging event. In the Sao Khua Formation of Thailand, isolated tooth crowns from "Siamosaurus" have been found in association with sauropod remains, indicating possible predation or scavenging.
Fossil remains of "Neovenator" have been found on the Isle of Wight off southern England, and were first discovered in the 20th century. "Neovenator" perhaps existed alongside other dinosaurs found in the Wessex Formation of the early Cretaceous period, such as "Baryonyx", "Polacanthus" and "Iguanodon". The holotype bones were mixed with those of the plant-eater "Mantellisaurus" and in the dig site also remains of fishes, amphibians, lizards, pterosaurs and Goniopholididae were present. "Neovenator" was one of the apex predators of its day.
In 2016, the Spanish palaeontologist Alejandro Serrano-Martínez and colleagues reported the oldest known spinosaurid fossil, a tooth from the Middle Jurassic of Niger, which they found to suggest that spinosaurids originated in Gondwana, since other known Jurassic spinosaurid teeth are also from Africa, but they found the subsequent dispersal routes unclear. Candeiro and colleagues suggested in 2017 that spinosaurids of northern Gondwana were replaced by other predators, such as abelisauroids, since no definite spinosaurid fossils are known from after the Cenomanian anywhere in the world. They attributed the disappearance of spinosaurids and other shifts in the fauna of Gondwana to changes in the environment, perhaps caused by transgressions in sea level.