Gemma Tarlach on Dead Things discusses a recently resolved mystery:
Published recently in American Museum Novitates, a new high-tech reinvestigation of a well-preserved fossil first described in 2003 revealed the animal was more than an Early Devonian sharklike fish.
Though its swimming days ended about 400 million years ago, this fossilized fella — with the great name of Doliodus problematicus — has found its place as a missing link in the deep backstory of some of today’s most intriguing and iconic animals. …
Now that we’ve got all the big words out of the way, what does the new research tell us? Well, it’s pretty exciting: thanks to CT scanning, researchers now consider Doliodus to be a truly transitional animal, an acanthodian on its way to becoming a chondrichthyan — a snapshot of the evolutionary process.
In some ways, Doliodus is the shark equivalent of our own famous distant kin Lucy, the Australopithecus afarensis from Ethiopia: We can see primitive traits hanging on in a species while derived, or more evolved features, arise.
