A two-fingered dinosaur may help researchers better understand how animals lose fingers and toes through evolution.

Oviraptorids , a group of bird-like dinosaurs that lived in what is now China and Mongolia 100 million years ago, usually had three fingers on each hand. But a set of juvenile skeletons confiscated from fossil poachers at the Mongolia-China border in 2006 have revealed two-fingered hands, suggesting an adaptation.

Gregory Funston at the University of Edinburgh in the UK and his colleagues have named the dinosaurs Oksoko avarsan , after a three-headed eagle in Mongolian mythology and …