Bambiraptor
Encyclopedia
Bambiraptor is a Late Cretaceous
Late Cretaceous
The Late Cretaceous is the younger of two epochs into which the Cretaceous period is divided in the geologic timescale. Rock strata from this epoch form the Upper Cretaceous series...

, 75 million year old, bird-like dromaeosaurid theropod dinosaur
Dinosaur
Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...

 described by scientists at the University of Kansas
University of Kansas
The University of Kansas is a public research university and the largest university in the state of Kansas. KU campuses are located in Lawrence, Wichita, Overland Park, and Kansas City, Kansas with the main campus being located in Lawrence on Mount Oread, the highest point in Lawrence. The...

, Yale University
Yale University
Yale University is a private, Ivy League university located in New Haven, Connecticut, United States. Founded in 1701 in the Colony of Connecticut, the university is the third-oldest institution of higher education in the United States...

, and the University of New Orleans
University of New Orleans
The University of New Orleans, often referred to locally as UNO, is a medium-sized public urban university located on the New Orleans Lakefront within New Orleans, Louisiana, United States. It is a member of the LSU System and the Urban 13 association. Currently UNO is without a proper chancellor...

.

The holotype fossil is less than one meter long, although this specimen appears to be a juvenile, and it is possible that Bambiraptor is really just a juvenile Saurornitholestes
Saurornitholestes
Saurornitholestes is a genus of carnivorous dromaeosaurid theropod dinosaur from the late Cretaceous of Alberta, Montana and New Mexico....

. Because of its small size, it was christened Bambiraptor feinbergi, after the familiar Disney
Walt Disney Pictures
Walt Disney Pictures is an American film studio owned by The Walt Disney Company. Walt Disney Pictures and Television, a subsidiary of the Walt Disney Studios and the main production company for live-action feature films within the Walt Disney Motion Pictures Group, based at the Walt Disney...

 movie character and the surname of the wealthy family who bought and lent the specimen to the new Graves Museum of Natural History in Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...

.

Discovery

The Bambiraptor skeleton was discovered in 1993 by 14-year-old fossil hunter Wes Linster, who was looking for dinosaur bones with his parents near Glacier National Park in Montana
Montana
Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...

. 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
Rosetta Stone
The Rosetta Stone is an ancient Egyptian granodiorite stele inscribed with a decree issued at Memphis in 196 BC on behalf of King Ptolemy V. The decree appears in three scripts: the upper text is Ancient Egyptian hieroglyphs, the middle portion Demotic script, and the lowest Ancient Greek...

' that enabled archaeologists to translate Egyptian hieroglyphics. Yale paleontologist John Ostrom
John Ostrom
John H. Ostrom was an American paleontologist who revolutionized modern understanding of dinosaurs in the 1960s, when he demonstrated that dinosaurs are more like big non-flying birds than they are like lizards , an idea first proposed by Thomas Henry Huxley in the 1860s, but which had garnered...

, who reintroduced the theory of bird evolution from dinosaurs
Dinosaur-bird connection
The origin of birds is a contentious and central topic within evolutionary biology. A close relationship between birds and dinosaurs was first proposed in the nineteenth century after the discovery of the primitive bird Archaeopteryx in Germany...

 after his 1964 discovery of Deinonychus
Deinonychus
Deinonychus was a genus of carnivorous dromaeosaurid dinosaur. There is one described species, Deinonychus antirrhopus. This 3.4 meter long dinosaur lived during the early Cretaceous Period, about 115–108 million years ago . Fossils have been recovered from the U.S...

 in Wyoming
Wyoming
Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...

, 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 was first seen as the young of Saurornitholestes and in 1997 reported as belonging to a Velociraptor sp. In 2000 it was named and described by David Burnham, Kraig Derstler, Phil Currie
Phil Currie
Philip John Currie, AOE is a Canadian palaeontologist and museum curator who helped found the Royal Tyrrell Museum of Palaeontology in Drumheller, Alberta and is now a professor at the University of Alberta in Edmonton...

, Robert Bakker, Zhou Zhonge and John Ostrom as a separate species: Bambiraptor feinbergi. The generic name is derived from Bambi
Bambi
Bambi is a 1942 American animated film directed by David Hand , produced by Walt Disney and based on the book Bambi, A Life in the Woods by Austrian author Felix Salten...

, in reference to the young age of the specimen, and a Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...

 raptor, "seizer". The specific epithet honours Michael en Ann Feinberg who acquired the specimen from a fossil dealer and made it available to science. In 2000 George Olshevsky
George Olshevsky
George Olshevsky is a freelance editor, writer, publisher, amateur paleontologist, and mathematician living in San Diego, California.Olshevsky maintains the comprehensive online Dinosaur Genera List...

 suggested the emended epithet "feinbergorum", the plural
Plural
In linguistics, plurality or [a] plural is a concept of quantity representing a value of more-than-one. Typically applied to nouns, a plural word or marker is used to distinguish a value other than the default quantity of a noun, which is typically one...

 genitive, and this was followed by some authors but such emendations are no longer allowed by the ICZN
International Code of Zoological Nomenclature
The International Code of Zoological Nomenclature is a widely accepted convention in zoology that rules the formal scientific naming of organisms treated as animals...

.

The holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...

 specimen AMNH FR 30554 (previously AMNH 001 and FIP 001), was uncovered in layers of the Upper Two Medicine Formation
Two Medicine Formation
The Two Medicine Formation is a geologic formation, or rock body, that was deposited between 83.5 ± 0.7 Ma to 70.6 ± 0.6 Ma , during Campanian time, and is located in northwestern Montana...

 dating to the late Campanian
Campanian
The Campanian is, in the ICS' geologic timescale, the fifth of six ages of the Late Cretaceous epoch . The Campanian spans the time from 83.5 ± 0.7 Ma to 70.6 ± 0.6 Ma ...

. It is currently housed at the American Museum of Natural History
American Museum of Natural History
The American Museum of Natural History , located on the Upper West Side of Manhattan in New York City, United States, is one of the largest and most celebrated museums in the world...

, 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
Paratype
Paratype is a technical term used in the scientific naming of species and other taxa of organisms. The exact meaning of the term paratype when it is used in zoology is not the same as the meaning when it is used in botany...

 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.

Description

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 ft), and an estimated total length of one metre. It perhaps weighed only two kilograms (4.4 lb). In 2010 Gregory S. Paul
Gregory S. Paul
Gregory Scott Paul is a freelance researcher, author and illustrator who works in paleontology, and more recently has examined sociology and theology. He is best known for his work and research on theropod dinosaurs and his detailed illustrations, both live and skeletal...

 estimated the adult length at 1.3 metres, the weight at five kilogrammes. It had long hindlimbs, indicating it could have been a fast runner. It also had very long arms and a well-developed wishbone.

Forelimbs

Research done by Phil Senter of the Lamar State College in Orange, Texas
Orange, Texas
Orange is a city in Orange County, Texas, United States. As of the 2000 census, the city population was 18,643. It is the county seat of Orange County, and is the easternmost city in Texas. Located on the Sabine River at the border with Louisiana, it is part of the Beaumont–Port Arthur...

 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. 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.

Brain

Bambiraptor had a brain size in the lower range of modern bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...

s. Because of its enlarged cerebellum
Cerebellum
The cerebellum is a region of the brain that plays an important role in motor control. It may also be involved in some cognitive functions such as attention and language, and in regulating fear and pleasure responses, but its movement-related functions are the most solidly established...

, 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

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
Cladistics
Cladistics is a method of classifying species of organisms into groups called clades, which consist of an ancestor organism and all its descendants . For example, birds, dinosaurs, crocodiles, and all descendants of their most recent common ancestor form a clade...

 analysis was a member of a group, Paraves
Paraves
Paraves is a branch-based clade containing birds and other closely related dinosaurs. The paravians include the Avialae, including Archaeopteryx and modern birds, and the Deinonychosauria, which includes the dromaeosaurids and troodontids....

, that contained feathered true birds and that was the sister taxon of Oviraptorosauria
Oviraptorosauria
Oviraptorosaurs are a group of feathered maniraptoran dinosaurs from the Cretaceous Period of what are now Asia and North America. They are distinct for their characteristically short, beaked, parrot - like skulls, with or without bony crests atop the head...

, a group that also had feathered forms (e.g. Caudipteryx
Caudipteryx
Caudipteryx is a genus of peacock-sized theropod dinosaurs that lived in the Aptian age of the early Cretaceous Period . They were feathered and remarkably birdlike in their overall appearance....

), Bambiraptor most likely had feathers too due to phylogenetic bracketing. Most paleontologists support Cooley's view, and subsequent discoveries confirmed that small dromaeosaurid dinosaurs like Bambiraptor were fully covered in feathers (see Dromaeosauridae
Dromaeosauridae
Dromaeosauridae is a family of bird-like theropod dinosaurs. They were small- to medium-sized feathered carnivores that flourished in the Cretaceous Period. The name Dromaeosauridae means 'running lizards', from Greek dromeus meaning 'runner' and sauros meaning 'lizard'...

 for more information).

Phylogeny

Bambiraptor was assigned to the Dromaeosauridae
Dromaeosauridae
Dromaeosauridae is a family of bird-like theropod dinosaurs. They were small- to medium-sized feathered carnivores that flourished in the Cretaceous Period. The name Dromaeosauridae means 'running lizards', from Greek dromeus meaning 'runner' and sauros meaning 'lizard'...

 in 2000. Subsequent cladistic analyses differ in the position of Bambiraptor: it has been recovered in the Velociraptorinae
Velociraptorinae
Velociraptorinae is a subfamily of the theropod group Dromaeosauridae. Velociraptorine remains are found mostly in northern hemisphere. In Late Cretaceous, they are mostly present in Mongolia, Romania and China,and in early, in USA. The earliest velociraptorines are probably Nuthetes from the...

, Microraptoria and most recently in the Saurornitholestinae
Saurornitholestinae
Saurornitholestinae is a subfamily of Dromaeosauridae.-Species:...

.

External links

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