Velociraptor (; ) is a genus of small dromaeosaurid that lived in Asia during the Late Cretaceous epoch, about 75 million to 71 million years ago (Mya). Two species are currently recognized, although others have been assigned in the past. The type species is V. mongoliensis, named and described in 1924. of this species have been discovered in the Djadochta Formation, Mongolia. A second species, V. osmolskae, was named in 2008 for skull material from the Bayan Mandahu Formation, China. A possible record is known from the Nemegt Formation.
Smaller than other dromaeosaurids like Deinonychus and Achillobator, Velociraptor was about long with a body mass of around . It nevertheless shared many of the same anatomy features. It was a , carnivore with a long tail and an enlarged sickle-shaped claw on each hindfoot, which is thought to have been used to tackle and restrain Predation. Velociraptor can be distinguished from other dromaeosaurids by its long and low skull, with an upturned snout.
Velociraptor (commonly referred to as "raptor") is one of the dinosaur genera most familiar to the general public due to its prominent role in the Jurassic Park films. In reality, however, Velociraptor was roughly the size of a turkey, considerably smaller than the approximately tall and reptiles seen in the novels and films (which were based on members of the related genus Deinonychus). Today, Velociraptor is well known to paleontology, with over a dozen described fossil skeletons. One particularly famous specimen preserves a Velociraptor locked in combat with a Protoceratops.
While North American teams were shut out of communist Mongolia during the Cold War, expeditions by Soviet Union and Polish scientists, in collaboration with Mongolian colleagues, recovered several more specimens of Velociraptor. The most famous is part of the "Fighting Dinosaurs" specimen (MPC-D 100/25; formerly IGM, GIN, or GI SPS), discovered by a Polish-Mongolian team in 1971. The fossil preserves a Velociraptor in battle against a Protoceratops. It is considered a national treasure of Mongolia, and in 2000 it was loaned to the American Museum of Natural History in New York City for a temporary exhibition.
Between 1988 and 1990, a joint China-Canadians team discovered Velociraptor remains in northern China. American scientists returned to Mongolia in 1990, and a joint Mongolian-American expedition to the Gobi, led by the American Museum of Natural History and the Mongolian Academy of Sciences, turned up several well-preserved skeletons. One such specimen, MPC-D 100/980, was nicknamed "Ichabodcraniosaurus" by Norell's team because the fairly complete specimen was found without its skull (an allusion to the Washington Irving character Ichabod Crane).Novacek, Michael J. (1996). Dinosaurs of the Flaming Cliffs. New York: Anchor Books. . While Norell and Makovicky provisionally considered it a specimen of Velociraptor mongoliensis, it was named as a new species Shri devi in 2021.
In 1999, Rinchen Barsbold and Halszka Osmólska reported a juvenile Velociraptor specimen (GIN or IGM 100/2000), represented by a complete skeleton including the skull of a young individual. It was found at the Tugriken Shireh locality of the Djadochta Formation during the context of the Mongolian-Japanese Palaeontological Expeditions. The coauthors stated that detailed descriptions of this and other specimens would be published at a later date.
Paleontologists Mark A. Norell and Peter J. Makovicky in 1997 described new and well preserved specimens of V. mongoliensis, namely MPC-D 100/985 collected from the Tugrik Shireh locality in 1993, and MPC-D 100/986 collected in 1993 from the Chimney Buttes locality. The team briefly mentioned another specimen, MPC-D 100/982, which by the time of this publication remained undescribed. In 1999 Norell and Makovicky provided more insights into the anatomy of Velociraptor with additional specimens. Among these, MPC-D 100/982 was partially described and figured, and referred to V. mongoliensis mainly based on cranial similarities with the holotype skull, although they stated that differences were present between the pelvic region of this specimen and other Velociraptor specimens. This relatively well-preserved specimen including the skull was discovered and collected in 1995 at the Bayn Dzak locality (specifically at the "Volcano" sub-locality). Martin Kundrát in a 2004 abstract compared the neurocranium of MPC-D 100/982 to another Velociraptor specimen, MPC-D 100/976. He concluded that the overall morphology of the former was more derived (advanced) than the latter, suggesting that they could represent distinct taxa.
Mark J. Powers in his 2020 master thesis fully described MPC-D 100/982, which he concluded to represent a new and third species of Velociraptor. This species, which he considered distinct, was stated to mainly differ from other Velociraptor species in having a shallow maxilla morphology. Powers and colleagues also in 2020 used morphometric analyses to compare several dromaeosaurid maxillae, and found the maxilla of MPC-D 100/982 to strongly differ from specimens referred to Velociraptor. They indicated that this specimen, based on these results, represents a different species. In 2021 Powers with team used Principal Component Analysis to separate dromaeosaurid maxillae, most notably finding that MPC-D 100/982 falls outside the instraspecific variability of V. mongoliensis, arguing for a distinct species. They considered that both V. mongoliensis and this new species were ecologically separated based on their skull anatomy. The team in another 2021 abstract reinforced again the species-level separation, noting that additional differences can be found in the hindlimbs.
Prominent quill knobs—attachment site of "wing" feathers and direct indicator of a feather covering—have been reported from the ulna of a single Velociraptor specimen (IGM 100/981), which represents an animal of estimated long and in weight. The spacing of 6 preserved knobs suggests that 8 additional knobs may have been present, giving a total of 14 quill knobs that developed large secondaries ("wing" feathers stemming from the forearm). However, the specimen number has been corrected to IGM 100/3503 and its referral to Velociraptor may require reevaluation, pending further study. Nevertheless, there is strong phylogenetic evidence from other dromaeosaurid relatives that indicates the presence of feathers in Velociraptor, including dromaeosaurids such as Daurlong, Microraptor, or Zhenyuanlong.
The lower jaw of Velociraptor comprised mainly the dentary, splenial, angular, surangular, and articular bones. The was a very long, weakly curved, and narrow element that developed several alveoli on its top surface. On its posterior end, it meet the . It had a small hole near its posterior end, called surangular foramen or fenestra. Both bones were the largest elements of the lower jaw of Velociraptor, contributing to virtually its entire length. Below them were the smaller and , closely articulated to each other. The , located on the inner side of the surangular, was a small element that joined the quadrate of the upper skull, enabling the articulation with the lower jaw. An elongated, near oval-shaped hole was developed in the center of the lower jaw (the mandibular fenestra), and it was produced by the joint of the dentary, surangular, and angular bones.
The teeth of Velociraptor were fairly homodont (equal in shape) and had several denticles (serrations), each more strongly serrated on the back edge than the front. The premaxilla had 4 alveoli (meaning that 4 teeth were developed), and the maxilla had 11 alveoli. At the dentary, between 14–15 alveoli were present. All teeth present at the premaxilla were poorly curved, and the two first teeth were the longest, with the second having a characteristic large size. The maxillary teeth were more slender, recurved, and most notably, the lower end was strongly more serrated than the upper one.
When first described in 1924, Velociraptor was placed in the family Megalosauridae, as was the case with most carnivorous dinosaurs at the time (Megalosauridae, like Megalosaurus, functioned as a sort of 'wastebin' taxon, where many unrelated species were grouped together). As dinosaur discoveries multiplied, Velociraptor was later recognized as a dromaeosaurid. All dromaeosaurids have also been referred to the family Archaeopterygidae by at least one author (which would, in effect, make Velociraptor a flightless bird). In the past, other dromaeosaurid species, including Deinonychus antirrhopus and Saurornitholestes langstoni, have sometimes been classified in the genus Velociraptor. Since Velociraptor was the first to be named, these species were renamed Velociraptor antirrhopus and V. langstoni.
Because of the presence of another dromaeosaurid in Ukhaa Tolgod, Tsaagan, Napoli and team have noted that the referral of this specimen to Velociraptor is currently subject to reexamination.
Manabu Sakamoto in 2022 performed a Bayesian phylogenetic predictive modelling framework for estimating jaw muscle parameters and bite forces of several extinct archosaurs, based on skull widths and phylogenetic relationships between groups. Among studied taxa, Velociraptor was scored with a bite force of 304 N, which was lower than that of other dromaeosaurids such as Dromaeosaurus (885 N) or Deinonychus (706 N).
Remains of Deinonychus, a closely related dromaeosaurid, have commonly been found in aggregations of several individuals. Deinonychus has also been found in association with the large ornithopod Tenontosaurus, which has been cited as evidence of cooperative (pack) hunting. However, the only solid evidence for social behavior of any kind among dromaeosaurids comes from a Chinese trackway which shows six individuals of a large species moving as a group. Although many isolated fossils of Velociraptor have been found in Mongolia, none were closely associated with other individuals. Therefore, while Velociraptor is commonly depicted as a pack hunter, as in Jurassic Park, there is only limited fossil evidence to support this theory for dromaeosaurids in general and none specific to Velociraptor itself. Dromeosaur footprints in China suggest that a few other raptor genera may have hunted in packs, but there have been no conclusive examples of pack behavior found.Long, John, and Schouten, Peter. (2008). Feathered Dinosaurs: The Origin of Birds. Oxford and New York: Oxford University Press. , p. 21.
In 2011, Denver Fowler and colleagues suggested a new method by which dromaeosaurs like Velociraptor and similar dromaeosaurs may have captured and restrained prey. This model, known as the "raptor prey restraint" (RPR) model of predation, proposes that dromaeosaurs killed their prey in a manner very similar to extant Accipitridae birds of prey: by leaping onto their quarry, pinning it under their body weight, and gripping it tightly with the large, sickle-shaped claws. These researchers proposed that, like accipitrids, the dromaeosaur would then begin to feed on the animal while it was still alive, and prey death would eventually result from blood loss and organ failure. This proposal is based primarily on comparisons between the morphology and proportions of the feet and legs of dromaeosaurs to several groups of extant birds of prey with known predatory behaviors. Fowler found that the feet and legs of dromaeosaurs most closely resemble those of and , especially in terms of having an enlarged second claw and a similar range of grasping motion. The short Tarsometatarsus and foot strength, however, would have been more similar to that of . The RPR method of predation would be consistent with other aspects of Velociraptors anatomy, such as their unusual jaw and arm morphology. The arms, which could exert a lot of force but were likely covered in long feathers, may have been used as flapping stabilizers for balance while atop a struggling prey animal, along with the stiff counterbalancing tail. The jaws, thought by Fowler and colleagues to be comparatively weak, would have been useful for row saw motion bites like the modern day Komodo dragon, which also has a weak bite, to finish off its prey if the kicks were not powerful enough. These predatory adaptations working together may also have implications for the origin of flapping in .
In 2012, Hone and colleagues published a paper that described a Velociraptor specimen with a long bone of an azhdarchid pterosaur in its gut. This was interpreted as showing scavenging behaviour.
In a 2024 study by Tse, Miller, and Pittman et al., focusing on the skull morphology and bite forces of various dromaeosaurids, it was discovered that Velociraptor had high bite force resistance compared to other dromaeosaurids such as Dromaeosaurus itself and Deinonychus, the latter of which was much larger. It is theorized by the authors that high bite force resistance was an adaptation towards obtaining food through scavenging more often than through active predation in Velociraptor.
In 2023, Seishiro Tada and team examined the nasal cavities of ectotherm (cold-blooded) or endotherm (warm-blooded) species, in order to evaluate the thermoregulatory physiology of non-avian dinosaurs compared to these groups. They found that the size of the nasal cavity relative to the head size of extant endotherms is larger than those of extant ectotherms, and among taxa, Velociraptor was recovered below the extant endotherms level by reconstructing its nasal respiratory cavity. Tada with team suggested that Velociraptor and most other non-avian dinosaurs may not have possessed a fully or well-developed nasal thermoregulation apparatus as modern endothermic animals do.
In 2012 David Hone and team reported another injured Velociraptor specimen (MPC-D 100/54, roughly a sub-adult individual) found with the bones of an Azhdarchidae pterosaur within its stomach cavity, was carrying or recovering from an injury sustained to one broken rib. From evidence on the pterosaur bones, which were devoid of pitting or deformations from digestion, the Velociraptor died shortly after, possibly from the earlier injury. Nevertheless, the team noted that this broken ribs shows signs of bone healing.
V. osmolskae lived alongside the ankylosaurid Pinacosaurus mephistocephalus; alvarezsaurid Linhenykus; closely related dromaeosaurid Linheraptor; oviraptorids Machairasaurus and Wulatelong; protoceratopsids Bagaceratops and Protoceratops hellenikorhinus; and troodontids Linhevenator, Papiliovenator, and Philovenator. Sediments across the formation indicate a similar depositional environment to that of the Djadochta Formation.
The Djadochta Formation is separated into a lower Bayn Dzak Member and upper Turgrugyin Member. V. mongoliensis is known from both members, represented by numerous specimens. The Bayn Dzak Member (mainly Bayn Dzak locality) has yielded the oviraptorid Oviraptor; ankylosaurid Pinacosaurus grangeri; protoceratopsid Protoceratops andrewsi; and troodontid Saurornithoides. The younger Turgrugyin Member (mainly Tugriken Shireh locality) has produced the bird Elsornis; dromaeosaurid Mahakala: ornithomimid Aepyornithomimus; and protoceratopsid Protoceratops andrewsi.
V. mongoliensis has been found at many of the most famous and prolific Djadochta localities. The type specimen was discovered at the Flaming Cliffs site (sublocality of the larger Bayn Dzak locality/region), while the "Fighting Dinosaurs" were found at the Tugrik Shire locality (also known as Tugrugeen Shireh and many other spellings). The latter is notorious for its exceptional in situ fossil preservation. Based on deposits (such as structureless sandstones), it has been concluded that a large number of specimens were buried alive during powerful sand-bearing events, common to these paleoenvironments.
Production on Jurassic Park began before the discovery of the large dromaeosaurid Utahraptor was made public in 1991, but as Jody Duncan wrote about this discovery: "Later, after we had designed and built the raptor, there was a discovery of a raptor skeleton in Utah, which they labeled 'super-slasher.' They had uncovered the largest Velociraptor to date and it measured five-and-a-half-feet tall, just like ours. So we designed it, we built it, and then they discovered it. That still boggles my mind." Spielberg's name was briefly considered for naming of the new dinosaur in exchange for funding of field work, but no agreement was reached.
Jurassic Park and its sequel were released before the discovery that dromaeosaurs had feathers, so the Velociraptor in both films were depicted as scaled and featherless. For Jurassic Park III, the male Velociraptor was given quill-like structures along the back of the head and neck, but these structures do not resemble the feathers that Velociraptor would have had in reality due to reasons of continuity. The Jurassic World sequel trilogy ignored the feathers of Velociraptor, adhering to the designs from Jurassic Park. However, the dromaeosaur Pyroraptor was feathered for Jurassic World Dominion, along with other changes such as stiffening the tail to account for ossified tendons and de-pronating the hands.
Additional species
Description
Skull
Postcranial skeleton
Classification
Paleobiology
Feathers
Senses
Feeding
Predatory behavior
Scavenging behavior
Metabolism
Paleopathology
Paleoenvironment
Bayan Mandahu Formation
Djadochta Formation
Cultural significance
See also
External links
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