The fossilized skull of a 28 million-year-old whale may be the oldest evidence paleontologists have of echolocation. According to analysis of the new species of toothed whale, Cotylocara macei looked similar to modern-day dolphins and lived in shallow marine environments. It also had a deep cavity on the top of its head that would have stored air during dives and may have reflected sound.
“The anatomy of the skull is really unusual,” Jonathan Geisler, a professor of anatomy at the New York Institute of Technology College of Osteopathic Medicine and lead author of the study, said in a statement. “I’ve not seen anything like this in any other whale, living or extinct.”
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