In a study published in Nature this week, researchers now say that a fossilized whale skull discovered outside Charleston, SC presents all the tell-tales signs related to echolocation in present-day toothed whales, dolphins, and porpoises. The skull is approximately 28 million years old, belonged to what's now the oldest known creature to use echolocation to hunt.
First known ancestor
According to Nature World News, the ancient whale, classified as Cotylocara macei, existed in the same era as when toothed whales and non-toothed whales branched off on the evolutionary tree. That split occurred between 32 and 34 million years ago, meaning that echolocation evolved as far back as that time. "The most important conclusion of our study involves the evolution of echolocation and the complex anatomy that underlies this behavior," said lead study author Jonathan Geisler, a professor of anatomy at the New York Institute of Technology College of Osteopathic Medicine. Researchers say that the whale was slightly larger than a modern bottlenose dolphin and, crucially, has the asymmetrical skull structure and nasal passages that would allow for the vocalizations used in echolocative function. Nevertheless, the skull itself is rather unique. I've not seen anything like this in any other whale, living or extinct," Geisler said.
The find comes as something of a surprise given where it was found — a drainage ditch outside a housing development in College Park, SC. Construction began in the area in the 1970s, unearthing several fossils in the process. "You never know what you'll find in your backyard," said Dr. Geisler.