In the past, partial fossils of juvenile Cosmopolitodus ... These fossilized bones showed debilitating teeth marks on the dolphin's ribs that were attributed to Cosmopilitodus hastalis, per ...

A dolphin fossil believed to be at least 25 million ... under five minutes as an ancestor of whales and dolphins. “Their teeth were a little different, their habits were a little.

teeth and other skull parts. Because dolphins use ultrasonic waves to sense their surroundings, their ears are characterized by complicated structures. The fossil bore no similarities to other ...