Velociraptor: the small bumps that revealed its feathers
Velociraptor had feathers, and the evidence is more than a guess. A fossil arm bone carries small bumps called quill knobs. In living birds, such bumps help anchor large feathers. Researchers reported them in Velociraptor in 2007. Tiny marks on bone changed the picture of a famous dinosaur. Feathers can disappear while the harder bone remains. An attachment mark can therefore preserve evidence of something no longer visible. This gives scientists another way to look for soft body coverings. [1] [2] [Further source]
Evidence on an arm bone
The fossil came from Mongolia. Six evenly spaced bumps were identified on its forearm. Their position matched the places where feathers attach in birds. The feathers themselves did not have to survive to leave this clue. Their connection to the skeleton recorded evidence of their presence. The bumps are part of the bone's surface. They are not painted feather outlines or marks added by an artist. Their spacing and position made them useful for comparison with bird wings. [1] [2] [Further source]
Feathers without flight
Feathers do not automatically mean an animal could fly. Velociraptor was a ground-dwelling predator. Feathers can also help with warmth, display and covering eggs. Which jobs mattered most for Velociraptor remains harder to establish. The arm bone tells us more about the feathers than their daily use. Microraptor, a related dinosaur, preserves clear feather evidence too. Archaeopteryx shows another combination of feathers and birdlike wings. These comparisons help explain why a feathered body is not a guarantee of the same flying ability. [1] [2] [Further source]
A different-looking raptor
A feathered Velociraptor would look different from many older movie versions. Its arms would carry a clear fringe of long feathers. The rest of its covering is reconstructed using the wider fossil evidence. Artists still have to make choices about details such as colour. The feathered arms, however, have a firm basis in the bones. A reconstruction can make the feather evidence visible to a reader. It cannot recover an exact coat pattern from quill knobs alone. Keeping the feathers while treating colours carefully makes better use of what the fossil actually shows. [1] [2] [Further source]