New view of dinosaurs could radically reshape their family tree – Los Angeles Times

The dinosaur family tree may need to be radically rewritten — and even uprooted and replanted elsewhere, a new analysis of about 75 different species shows.

The findings, published in the journal Nature, hint that dinosaurs may have originated in the northern hemisphere rather than the southern, and could upend an understanding of dinosaur evolution that has gone largely unchallenged for some 130 years.

“We might all have to rearrange our mental furniture,” Kevin Padian, a UC Berkeley professor of integrative biology who was not involved in the study, wrote in a commentary.

To figure out the family tree of long-extinct animals with fossilized bones, scientists have to carefully study their shared features to see which ancient species were related, and what their common ancestors looked like. It’s tricky and painstaking work, especially since similar physical features can sometimes emerge independently in two different species — a phenomenon known as convergent evolution. (Wings emerged separately in birds and bats, for example.)

New view of dinosaurs could radically reshape their family tree – Los Angeles Times