Email
Print
ShareWASHINGTON: In a new study, three students from Montana State University, US, have explored the gruesome world of raptors.
Normally focused on dinosaurs, the students compared the claws and killing methods of four types of raptors.
The birds of prey that were studied live in North America and Europe and include eagles and hawks, owls, osprey and falcons.
Lead author Denver Fowler, Elizabeth Freedman and John Scannella - all MSU graduate students who conduct paleontology research in MSU's Museum of the Rockies - planned to investigate a box of raptor feet stored in the museum.
The graduate students thought that examining the feet was a small project they could do over spring break a few years ago, but it took far longer and became much more involved than they expected.
By the time they finished, they were immersed in a violent world where some raptors dismember their prey and eat them alive.
Depending on the type of raptor, the birds of prey break necks, pry open body cavities, pierce internal organs and strike killing blows.
Fowler and his co-authors examined hundreds of raptor claws, photographs and videos to understand raptor-prey interactions.
They measured the length and curvature of claws, then compared them.
They surveyed preserved skins and mounts in MSU's ecology department, the Museum of the Rockies and the American Museum of Natural History.
They learned that talons varied in shape and size among families of raptors, and that this was related to differences in killing technique.
All raptors hold small prey inside their feet and immobilize them by constriction.
"Owls only tend to eat small prey, so they have feet and claws specialized for high grip strength, making them more efficient constrictors," Fowler said.
The team found that hawks and eagles have specially enlarged talons, which evolved to restrain large, struggling prey by embedding deep, keeping an anchor hold while the raptor stands on top, and immobilizing prey by dismemberment.
Falcons only use their talons to prevent their prey from escaping, according to Fowler.
They generally strike their prey at high speeds, then use a "tooth" on their beak to break its neck or crush the head.
Osprey have talons that are large, highly curved and nearly uniform, especially good for catching fish.
"Studying raptor claws fills a need in raptor research, but it may also apply to dinosaurs," Fowler said.
