Jurassic Dad

Birds are like nothing else on Earth--in the sense that they have lots of traits in common that are not found in quite the same package in other animals. All birds have feathers, for example, and they can either fly or have evolved from birds that once flew. You don't see some feathered reptile running around on all fours. But that distinctness is merely an artefact of extinctions. The closest living relatives of birds today are alligators and crocs, and they share a common ancestor that lived some 250 million years ago. All of the species on the lineage that led from that ancestor to birds are extinct. The ground-running dinosaurs disappeared. There are fossils of birds that could fly 120 million years ago, but they became extinct too. To see how birds became so unique, scientists have to burrow down the evolutionary tree, and burrow into the ground. I've ...