[Author’s note: The book is in, and the field season is here. I’m going out for a week of fieldwork to clear my brain (and, of course, look for fossils). In the meantime, here’s a post from late last year about what whales and pelicans share in common.]

Pelicans and whales are not especially close relatives. I’m about as closely related to Tyrannosaurus rex as they are to each other. The specialized, flying dinosaurs and the highly modified, aquatic artiodactyls (who long ago lost their hooves) last shared a common ancestor over 306 million years ago in