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Small fully feathered dromaeosaur with wing feathers and a long tail, in side view
Artistic restoration of Velociraptor mongoliensis. 画像クレジット:Fred Wierum, CC BY-SA 4.0, via Wikimedia Commons (unmodified except resizing)CC BY-SA 4.0(無改変)出典(新しいタブで開きます)

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Did Velociraptor have feathers? Yes. No Velociraptor fossil preserves the feathers themselves, but a forearm bone of Velociraptor mongoliensis carries a row of small bumps called quill knobs. In living birds, these are the anchor points for large wing feathers. Together with feathered fossils of its close relatives, that makes a feathered Velociraptor the best-supported reconstruction.

Velociraptor at a glance

  • Size: about 1.5 m long and roughly 15 kg; closer to a large turkey than to the film version.
  • When: the Campanian age of the Late Cretaceous, roughly 84 to 72 million years ago.
  • Where: the Djadokhta Formation of the Gobi Desert, in Mongolia.
  • Group: dromaeosaurids, the "raptors", close relatives of birds.
  • Named: by Henry Fairfield Osborn in 1924.

Where Velociraptor was found

The first Velociraptor fossils were collected in 1923 at the Flaming Cliffs in the Gobi, by the American Museum of Natural History's Central Asiatic Expeditions. Osborn named the species the next year from a crushed skull and a claw, specimen AMNH 6515.

The Djadokhta rocks formed in a dry landscape of sand dunes and seasonal streams. Many skeletons there are complete and articulated, which suggests that animals were buried quickly, perhaps by collapsing dunes or sandstorms. That fast burial is why the Gobi has produced so many well-preserved small dinosaurs, eggs and nests.

The 'Fighting Dinosaurs' at Tugrugeen Shireh, Gobi Desert, photographed during their excavation by the Polish-Mongolian expedition in August 1971. 画像クレジット:Tomasz Jerzykiewicz, CC BY-SA 4.0, via Wikimedia Commons (unmodified except resizing)CC BY-SA 4.0(無改変)出典(新しいタブで開きます)

Did Velociraptor have feathers? The quill knob evidence

In 2007, Alan Turner, Peter Makovicky and Mark Norell described a forearm bone (the ulna) from an adult Velociraptor, specimen IGM 100/981. Along the back of the bone runs a line of evenly spaced bumps.

Modern birds have the same feature. In a bird's wing, the large secondary flight feathers are tied to the ulna by ligaments, and those attachments leave raised knobs on the bone. Finding them on Velociraptor means it had well-developed feathers on its arms, not just a fuzzy covering.

Quill knobs are not found on every bird, so their absence would not prove an animal lacked feathers. Their presence, though, is hard to explain any other way.

Feathered relatives preserved in stone

The second line of evidence comes from Velociraptor's relatives. In some rocks, especially fine-grained lake and lagoon deposits, feathers are preserved as dark impressions around the skeleton:

Because feathered animals sit on both sides of Velociraptor in the family tree, the simplest explanation is that it inherited feathers too. Palaeontologists call this reasoning phylogenetic bracketing.

Microraptor zhaoianus fossil at the Henan Geological Museum, Zhengzhou. 画像クレジット:Gary Todd, CC0, via Wikimedia Commons, Henan Geological MuseumCC0 1.0出典(新しいタブで開きます)

What kind of feathers?

Not all dinosaur feathers were alike. The simplest were hair-like filaments, the kind seen on Yutyrannus, which probably worked as insulation. More advanced were pennaceous feathers: a central shaft with a flat vane on each side, the design of the flight feathers in a bird's wing. Quill knobs anchor exactly this kind of large, vaned feather, so Velociraptor's arm feathers were probably pennaceous. Its body was likely covered in smaller, simpler feathers, as in its relatives, though no fossil shows Velociraptor's body covering directly.

Why doesn't Velociraptor look like the movies?

The animals in Jurassic Park were scaled up well beyond Velociraptor and shown with scaly skin. In size and build they are closer to larger dromaeosaurids such as Deinonychus, about 3.3 m long, from the Cloverly Formation of the western United States, or the even bigger Utahraptor.

A more accurate Velociraptor would look bird-like: a feathered body, a feathered tail, and arms with a fan of long feathers, ending in three clawed fingers. On each foot it had an enlarged, curved second-toe claw that it could hold off the ground.

Could Velociraptor fly?

No. Its arms were far too short relative to its body, and at around 15 kg it was much too heavy for its feathers to lift it. Its wing feathers must have had other jobs. Palaeontologists have proposed several, and they are not mutually exclusive:

  • Display: showing off to rivals or mates, as many birds do today.
  • Brooding: covering eggs. Fossils of oviraptorid dinosaurs, which also lived in the Gobi, have been found sitting on nests with their arms spread over the eggs (Norell et al. 1995).
  • Balance while hunting: Denver Fowler and colleagues (2011) suggested that dromaeosaurids pinned prey with their feet and flapped their arms to stay steady on top of it.

These are hypotheses based on anatomy and comparisons with living animals, not direct observations.

The fighting dinosaurs

The most famous Velociraptor fossil shows one locked in combat with a Protoceratops, a sheep-sized plant eater. The two were buried together, apparently in the middle of the struggle, with Velociraptor's foot claw near the Protoceratops's throat and its arm caught in the Protoceratops's jaws.

The 'Fighting Dinosaurs': a Velociraptor locked in combat with a Protoceratops, preserved together, as exhibited in Japan. 画像クレジット:Yuya Tamai from Gifu, Japan, CC BY 2.0, via Wikimedia CommonsCC BY 2.0出典(新しいタブで開きます)

Other finds show that Velociraptor also fed on Protoceratops carcasses: Hone and colleagues (2010) described Protoceratops bones with Velociraptor tooth marks, probably left while scavenging.

So, what did Velociraptor look like?

Picture a lean, fast, turkey-sized predator with a long, stiff tail, a narrow snout full of serrated teeth and a coat of feathers, with bigger ones on its arms. The exact colours are unknown for Velociraptor, since no pigment has been preserved.

See the evidence, fossils and sources on the Velociraptor profile, or browse all carnivorous dinosaurs on DinoDex.

Sources

  1. Turner, A. H., Makovicky, P. J. & Norell, M. A.. (2007). Feather quill knobs in the dinosaur Velociraptor. Science 317(5845): 1721 doi:10.1126/science.1145076
  2. Osborn, H. F.. (1924). Three new Theropoda, Protoceratops zone, central Mongolia. American Museum Novitates 144: 1-12
  3. Hone, D., Choiniere, J., Sullivan, C., Xu, X., Pittman, M. & Tan, Q.. (2010). New evidence for a trophic relationship between the dinosaurs Velociraptor and Protoceratops. Palaeogeography, Palaeoclimatology, Palaeoecology 291(3-4): 488-492 doi:10.1016/j.palaeo.2010.03.028
  4. Fowler, D. W., Freedman, E. A., Scannella, J. B. & Kambic, R. E.. (2011). The predatory ecology of Deinonychus and the origin of flapping in birds. PLoS ONE 6(12): e28964 doi:10.1371/journal.pone.0028964
  5. Norell, M. A., Clark, J. M., Chiappe, L. M. & Dashzeveg, D.. (1995). A nesting dinosaur. Nature 378: 774-776 doi:10.1038/378774a0
  6. Xu, X., Wang, K., Zhang, K., Ma, Q., Xing, L., Sullivan, C., Hu, D., Cheng, S. & Wang, S.. (2012). A gigantic feathered dinosaur from the Lower Cretaceous of China. Nature 484: 92-95 doi:10.1038/nature10906
  7. Foth, C., Tischlinger, H. & Rauhut, O. W. M.. (2014). New specimen of Archaeopteryx provides insights into the evolution of pennaceous feathers. Nature 511: 79-82 doi:10.1038/nature13467

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