Bambiraptor

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Bambiraptor
Temporal range: Late Cretaceous, 72  Ma
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Dans l'ombre des dinosaures - Bambiraptor jeune - 04.jpg
Restored skeleton of the juvenile specimen
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Saurischia
Clade: Theropoda
Family: Dromaeosauridae
Clade: Eudromaeosauria
Subfamily: Saurornitholestinae
Genus: Bambiraptor
Burnham et al., 2000
Type species
Bambiraptor feinbergi
Burnham et al., 2000

Bambiraptor is a Late Cretaceous, 72-million-year-old, bird-like dromaeosaurid theropod dinosaur described by scientists at the University of Kansas, Yale University, and the University of New Orleans.

Contents

The holotype fossil is less than one meter long, although this specimen appears to be a juvenile, [1] and it is possible that Bambiraptor is a juvenile Saurornitholestes . [2] It is even suspected that the type specimen is a chimera, based on the fact that "there are elements of three different similarly sized lower legs included in the holotype." [2] Because of its small size, it was named Bambiraptor feinbergi, after the popular Disney movie character (the name literally translates to "Bambi thief") and the surname of the wealthy family who bought and lent the specimen to the new Graves Museum of Natural History in Florida.

Discovery

Cast of the fossil slab BambiraptorFeinbergi RoyalOntarioMuseum.png
Cast of the fossil slab

The Bambiraptor skeleton was discovered in 1995 by 14-year-old fossil hunter WES LINSTER , who was looking for dinosaur bones with his parents near Glacier National Park in Montana, United States. Linster told Time magazine that he uncovered the skeleton on a tall hill and was amazed at his discovery. "I bolted down the hill to get my mom because I knew I shouldn't be messing with it", he said. The bones that Linster discovered on that hilltop led to the excavation of a skeleton that was approximately 95 percent complete. Because of its completeness Florida Paleontology Institute Director Martin Shugar compared it to the Rosetta Stone that enabled archaeologists to translate Egyptian hieroglyphics. Yale paleontologist John Ostrom, who reintroduced the theory of bird evolution from dinosaurs after his 1964 discovery of Deinonychus in Wyoming, agreed, calling the specimen a "jewel", and telling reporters that the completeness and undistorted qualities of the bones should help scientists further understand the dinosaur-bird link.

The fossil first was seen as the young of Saurornitholestes and in 1997 reported as belonging to a Velociraptor sp. [3] In 2000 it was named and described by David Burnham, Kraig Derstler, Phil Currie, Robert Bakker, Zhou Zhonge and John Ostrom as a new genus: Bambiraptor feinbergi. The generic name is derived from Bambi, in reference to the young age of the specimen, and a Latin raptor, "seizer". The specific epithet honours Michael and Ann Feinberg who acquired the specimen from a fossil poacher and made it available to science. [4] In 2000 George Olshevsky suggested the emended epithet "feinbergorum", the plural genitive, and this was followed by some authors but such emendations are no longer allowed by the ICZN.

The holotype specimen AMNH FR 30556 (previously AMNH 001 and FIP 001, sometimes wrongly referred to as AMNH FR 30554), was uncovered in layers of the Upper Two Medicine Formation dating to the late Campanian. It is currently housed at the American Museum of Natural History, New York. It consists of a partially articulated largely complete skeleton with skull of a juvenile individual. Though the right side of the skeleton is damaged, most bones are uncompressed and well-preserved. The end of the tail is lacking. Also a paratype was assigned in 2000, FIP 002-136, consisting of thirty-four skeletal elements of at least two adult individuals found near the holotype. In 2004 an upper jaw bone was referred to the species, specimen MOR 553S-7-30-91-274. [5]

Description

Skeletal restoration Bambiraptor feinbergi.jpg
Skeletal restoration
Detail views of Bambiraptor. Bambiraptor details.jpg
Detail views of Bambiraptor.

While adult specimens are known, only the type specimen, a juvenile, has been described. This juvenile Bambiraptor has a preserved length of 90 centimetres (3.0 ft), [6] and an estimated total length of one metre. It perhaps weighed only two kilograms (4.4 lb). It had long hindlimbs, indicating it could have been a fast runner. It also had very long arms and a well-developed wishbone. According to an SVP abstract published in 2021, the holotype is 30-40% the size of specimen MOR 553S-7-30-91-274. Directly scaling up the holotype specimen gives a length of 2.5-3.3 m. However, this is likely a low estimate since the specimen is a maxilla with proportions like that of the holotype, and juvenile animals tend to have proportionally longer skulls. In 2010 Gregory S. Paul estimated the adult length at 1.3 metres (4.3 ft), the weight at five kilogrammes. [7]

Forelimbs

Restored skeleton in Oxford University Museum Bambiraptor2.png
Restored skeleton in Oxford University Museum

Research done by Phil Senter of the Lamar State College in Orange, Texas has indicated that Bambiraptor may have had mutually opposable first and third fingers and a forelimb maneuverability that would allow the hand to reach its mouth. [8] This would have given the animal the ability to "hold" food in its front limbs and place it in its mouth, in a similar manner to some modern-day small mammals. [9]

Brain

Bambiraptor had a brain size in the lower range of modern birds. Because of its enlarged cerebellum, which may indicate higher agility and higher intelligence than other dromaeosaurs, David A. Burnham has hypothesized that Bambiraptor feinbergi may have been arboreal. Life in the trees may have required evolutionary pressure that resulted in a larger brain. Burnham also offers an alternative hypothesis that a larger brain could be selected for as a result of hunting more agile prey items such as lizards and mammals. The Bambiraptor holotype had with 14 cm3 the largest brain for its size of any dinosaur yet discovered, although the brain size may be due to its age, because juvenile animals tend to have larger brain-to-body ratios compared to adults.

Feathers

Artist's restoration of the juvenile specimen Bambiraptor reconstruction.jpg
Artist's restoration of the juvenile specimen

During the conference where Bambiraptor was first introduced, the dinosaur reconstruction specialist Brian Cooley portrayed Bambiraptor as having feathers, despite the fact that no feathers were found with the fossil itself. His decision was influenced by the fact that because Bambiraptor within a cladistic analysis was a member of a group, Paraves, that contained feathered true birds and that was the sister taxon of Oviraptorosauria, a group that also had feathered forms (e.g. Caudipteryx), Bambiraptor most likely had feathers too due to phylogenetic bracketing. Most paleontologists support Cooley's view, and subsequent discoveries [ citation needed ] confirmed that small dromaeosaurid dinosaurs like Bambiraptor were fully covered in feathers (see Dromaeosauridae for more information).


Phylogeny

Bambiraptor was assigned to the Dromaeosauridae in 2000, though its position within the family remains uncertain, since subsequent cladistic analyses show different results. It has been recovered as a microraptorian or a saurornitholestine, [10] and the most recent phylogenetic analyses place it as a sister taxon or a member of Eudromaeosauria. [11] [12] [13]

See also

Related Research Articles

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Velociraptor is a genus of small dromaeosaurid dinosaurs that lived in Asia during the Late Cretaceous epoch, about 75 million to 71 million years ago. Two species are currently recognized, although others have been assigned in the past. The type species is V. mongoliensis, named and described in 1924. Fossils 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.

<i>Deinonychus</i> Genus of theropod dinosaur

Deinonychus is a genus of dromaeosaurid theropod dinosaur with one described species, Deinonychus antirrhopus. This species, which could grow up to 3.4 meters (11 ft) long, lived during the early Cretaceous Period, about 115–108 million years ago. Fossils have been recovered from the U.S. states of Montana, Utah, Wyoming, and Oklahoma, in rocks of the Cloverly Formation and Antlers Formation, though teeth that may belong to Deinonychus have been found much farther east in Maryland.

<span class="mw-page-title-main">Dromaeosauridae</span> Family of theropod dinosaurs

Dromaeosauridae is a family of feathered coelurosaurian theropod dinosaurs. They were generally small to medium-sized feathered carnivores that flourished in the Cretaceous Period. The name Dromaeosauridae means 'running lizards', from Greek δρομαῖος (dromaîos), meaning 'running at full speed', 'swift', and σαῦρος (saûros), meaning 'lizard'. In informal usage, they are often called raptors, a term popularized by the film Jurassic Park; several genera include the term "raptor" directly in their name, and popular culture has come to emphasize their bird-like appearance and speculated bird-like behavior.

<i>Dromaeosaurus</i> Extinct genus of dinosaurs

Dromaeosaurus is a genus of dromaeosaurid theropod dinosaur that lived during the Late Cretaceous period, sometime between 80 and 69 million years ago, in Alberta, Canada and the western United States. The type species is Dromaeosaurus albertensis, which was described by William Diller Matthew and Barnum Brown in 1922. Its fossils were unearthed in the Hell Creek Formation, Horseshoe Canyon Formation and Dinosaur Park Formation. Teeth attributed to this genus have been found in the Prince Creek Formation. Dromaeosaurus is the type genus of both Dromaeosauridae and Dromaeosaurinae, which include many genera with similar characteristics to Dromaeosaurus such as possibly its closest relative Dakotaraptor. Dromaeosaurus was heavily built, more so than other dromaeosaurs that are similar in size, like Velociraptor.

<i>Sinornithosaurus</i> Extinct genus of dinosaurs

Sinornithosaurus is a genus of feathered dromaeosaurid dinosaur from the early Cretaceous Period of the Yixian Formation in what is now China. It was the fifth non–avian feathered dinosaur genus discovered by 1999. The original specimen was collected from the Sihetun locality of western Liaoning. It was found in the Jianshangou beds of the Yixian Formation, dated to 124.5 million years ago. Additional specimens have been found in the younger Dawangzhangzi bed, dating to around 122 million years ago.

<i>Saurornitholestes</i> Extinct genus of dinosaurs

Saurornitholestes is a genus of carnivorous dromaeosaurid theropod dinosaur from the late Cretaceous of Canada (Alberta) and the United States.

<i>Atrociraptor</i> Extinct genus of dinosaurs

Atrociraptor is a genus of dromaeosaurid dinosaur that lived during the Late Cretaceous in what is now Alberta, Canada. The first specimen, a partial skull, was discovered in 1995 by the fossil collector Wayne Marshall in the Horseshoe Canyon Formation, about 5 km (3 mi) from the Royal Tyrrell Museum of Palaeontology, where it was brought for preparation. In 2004, the specimen became the holotype of the new genus and species Atrociraptor marshalli; the generic name is Latin for "savage robber", and the specific name references Marshall. The holotype consists of the premaxillae, a maxilla, the dentaries, associated teeth, and other skull fragments. Isolated teeth from the same formation have since been assigned to Atrociraptor.

<i>Adasaurus</i> Extinct genus of dinosaurs

Adasaurus is a genus of dromaeosaurid dinosaur that lived in Asia during the Late Cretaceous period about 70 million years ago. The genus is known from two partial specimens found in the Nemegt Formation of Mongolia that were partially described in 1983 by the paleontologist Rinchen Barsbold.

<i>Achillobator</i> Extinct dromaeosaurid genus from the Late Cretaceous

Achillobator is a genus of large dromaeosaurid theropod dinosaur that lived during the Late Cretaceous period about 96 million to 89 million years ago in what is now the Bayan Shireh Formation of Mongolia. The genus is currently monotypic, only including the type species A. giganticus. The first remains were found in 1989 during a Mongolian-Russian field expedition and later described in 1999. Remains at the type locality of Achillobator may represent additional specimens. It represents the first and largest dromaeosaurid known from the Bayan Shireh Formation.

<i>Zapsalis</i> Extinct genus of dinosaurs

Zapsalis is a genus of dromaeosaurine theropod dinosaurs. It is a tooth taxon, often considered dubious because of the fragmentary nature of the fossils, which include teeth but no other remains.

<i>Tsaagan</i> Extinct genus of dinosaurs

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<span class="mw-page-title-main">Velociraptorinae</span> Extinct subfamily of dinosaurs

Velociraptorinae is a subfamily of the theropod group Dromaeosauridae. Definitive fossils attributed to the subfamily have only been found in the Late Cretaceous deposits of Asia, with Kansaignathus as the basalmost member. While numerous taxa from North America are previously assigned to the velociraptorines, they are now reclassified within different lineages of Eudromaeosauria. Several teeth that may belong to indeterminate velociraptorines have also been discovered in Germany, dating to the Kimmeridgian stage of the Late Jurassic.

<i>Hesperonychus</i> Extinct genus of dinosaurs

Hesperonychus is a genus of small paravian theropod dinosaur. It may be a dromaeosaurid or an avialan. There is one described species, Hesperonychus elizabethae. The type species was named in honor of Dr. Elizabeth Nicholls of the Royal Tyrrell Museum of Palaeontology who collected it as a student in 1982. It is known from fossils recovered from the Dinosaur Park Formation and possibly from the uppermost strata of the Oldman Formation of Alberta, dating to the Campanian stage of the Late Cretaceous around 75 million years ago.

<span class="mw-page-title-main">Saurornitholestinae</span> Extinct subfamily of dinosaurs

Saurornitholestinae is a subfamily of the theropod group Dromaeosauridae. The saurornitholestines currently include monotypic genera Atrociraptor marshalli, Saurornitholestes langstoni, and possibly Bambiraptor feinbergi and Acheroraptor temertyorum. All are medium-sized dromaeosaurs from the Late Cretaceous of western North America. The group was originally recognized by Longrich and Currie as the sister taxon to a clade formed by the Dromaeosaurinae and Velociraptorinae. However, not all phylogenetic analyses recover this group and/or with the same proposed genera.

<i>Tianyuraptor</i> Extinct genus of dinosaurs

Tianyuraptor is a genus of short-armed dromaeosaurid dinosaur that lived during the Early Cretaceous, about 122 million years ago. Its remains have been found in western Liaoning, China. It was similar to other dromaeosaurids found in Liaoning, with the exception of being somewhat more primitive. The type specimen, formally named in 2009, shows features not seen in previously known Northern Hemisphere (Laurasian) dromaeosaurids, but present in Southern Hemisphere (Gondwanan) species and early birds. Because of this, the scientists who first studied Tianyuraptor described it as a "transitional species", bridging the gap between northern and southern types of dromaeosaurid. Tianyuraptor also differs from previously known dromaeosaurids in that it possesses a relatively small furcula ("wishbone"), and unusually short forelimbs.

<span class="mw-page-title-main">Eudromaeosauria</span> Extinct clade of dinosaurs

Eudromaeosauria is a subgroup of terrestrial dromaeosaurid theropod dinosaurs. They were small to large-sized predators that flourished during the Cretaceous Period. Eudromaeosaur fossils are known almost exclusively from the northern hemisphere.

<i>Acheroraptor</i> Dromaeosaurid dinosaur genus from the Late Cretaceous

Acheroraptor is an extinct genus of dromaeosaurid theropod dinosaur known from the latest Maastrichtian Hell Creek Formation of Montana, United States. It contains a single species, Acheroraptor temertyorum. A. temertyorum is one of the two geologically youngest known species of dromaeosaurids, the other being Dakotaraptor steini, which is also known from Hell Creek. A basal cousin of Velociraptor, Acheroraptor is known from upper and lower jaw material.

<span class="mw-page-title-main">Timeline of dromaeosaurid research</span>

This timeline of dromaeosaurid research is a chronological listing of events in the history of paleontology focused on the dromaeosaurids, a group of sickle-clawed, bird-like theropod dinosaurs including animals like Velociraptor. Since the Native Americans of Montana used the sediments of the Cloverly Formation to produce pigments, they may have encountered remains of the dromaeosaurid Deinonychus hundreds of years before these fossils came to the attention of formally trained scientists.

<i>Dakotaraptor</i> Extinct chimaeric genus of dinosaurs

Dakotaraptor is a chimaeric genus of maniraptoriform theropod dinosaur that lived in western North America during the Late Cretaceous period. The remains have been found in the Maastrichtian-aged Hell Creek Formation, dated to the very end of the Mesozoic era, making Dakotaraptor potentially one of the last surviving dromaeosaurids, though other researchers have disputed its classification. The remains of D. steini were discovered in a multi-species bonebed. Elements of the holotype and referred specimens were later found to belong to trionychid turtles, and it is unclear whether further analysis of potential non-dromaeosaurid affinities of the holotype and referred material can be properly conducted, because currently the type specimen is housed in private collection. Phylogenetic analyses of D. steini place it in a variety of positions within Dromaeosauridae.

<i>Dineobellator</i> Extinct genus of dinosaurs

Dineobellator is a genus of dromaeosaurid theropod dinosaur that lived in North America during the Late Cretaceous period 68 million years ago. The remains have been found in the Maastrichtian stage of the Naashoibito Member at the Ojo Alamo Formation, New Mexico.

References

  1. Archived April 20, 2006, at the Wayback Machine
  2. 1 2 Pittman, M.; O'Connor, J.; Tse, E.; Makovicky, P.; Field, D.J.; Ma, W.; Turner, A.H.; Norell, M.A.; Pei, R.; Xu, X. (2020). "Chapter 2 – The Fossil Record of Mesozoic and Paleocene Pennaraptorans" (PDF). In Pittman, M.; Xing, X. (eds.). Pennaraptoran Theropod Dinosaurs: Past Progress and New Frontiers. Bulletin of the American Museum Of Natural History. pp. 37–95. doi:10.17863/CAM.59245. ISSN   0003-0090.
  3. Burnham, D.A., Derstler K.L. and Linster, W., 1997, "A new specimen of Velociraptor (Dinosauria: Theropoda) from the Two Medicine Formation of Montana", Dinofest International Proceedings. pp 73-75
  4. Burnham, D.A., Derstler, K.L., Currie, P.J., Bakker, R.T., Zhou Z. & Ostrom J. H., 2000. "Remarkable new birdlike dinosaur (Theropoda: Maniraptora) from the Upper Cretaceous of Montana", University of Kansas Paleontological Contributions13: 1–14
  5. Burnham, D. A. (2004). "New Information on Bambiraptor feinbergi from the Late Cretaceous of Montana". In Philip J. Currie; E.B. Koppelhus; M.A. Shugar; J.L. Wright (eds.). Feathered Dragons: Studies on the Transition from Dinosaurs to Birds. Indianapolis: Indiana University Press. pp. 67–111. ISBN   0-253-34373-9.
  6. Holtz, Thomas R. Jr. (2011). Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages. ISBN   978-0375824197 Winter 2010 Appendix.
  7. Paul, G.S., 2010, The Princeton Field Guide to Dinosaurs, Princeton University Press p. 135
  8. Senter, P., 2006, "Comparison of forelimb function between Deinonychus and Bambiraptor (Theropoda: Dromaeosauridae)", Journal of Vertebrate Paleontology, 26(4): 897-906
  9. Archived September 30, 2007, at the Wayback Machine
  10. Longrich, N.R.; Currie, P.J. (2009). "A microraptorine (Dinosauria–Dromaeosauridae) from the Late Cretaceous of North America". Proceedings of the National Academy of Sciences. 106 (13): 5002–5007. Bibcode:2009PNAS..106.5002L. doi: 10.1073/pnas.0811664106 . PMC   2664043 . PMID   19289829.
  11. Currie, Philip J.; Evans, David C. (2020). "Cranial Anatomy of New Specimens of Saurornitholestes langstoni (Dinosauria, Theropoda, Dromaeosauridae) from the Dinosaur Park Formation (Campanian) of Alberta". The Anatomical Record. 303 (4): 691–715. doi: 10.1002/ar.24241 . PMID   31497925. S2CID   202002676.
  12. Jasinski, Steven E.; Sullivan, Robert M.; Dodson, Peter (December 2020). "New Dromaeosaurid Dinosaur (Theropoda, Dromaeosauridae) from New Mexico and Biodiversity of Dromaeosaurids at the end of the Cretaceous". Scientific Reports. 10 (1): 5105. Bibcode:2020NatSR..10.5105J. doi: 10.1038/s41598-020-61480-7 . PMC   7099077 . PMID   32218481.
  13. Jasinski, Steven E.; Sullivan, Robert M.; Carter, Aja M.; Johnson, Erynn H.; Dalman, Sebastian G.; Zariwala, Juned; Currie, Philip J. (2022-11-07). "Osteology and reassessment of Dineobellator notohesperus, a southern eudromaeosaur (Theropoda: Dromaeosauridae: Eudromaeosauria) from the latest Cretaceous of New Mexico" . The Anatomical Record. 306 (7): 1712–1756. doi:10.1002/ar.25103. ISSN   1932-8486. PMID   36342817. S2CID   253382718.