The skeleton of a 4.8-metre long dolphin ancestor that lived 25 million years ago in South Carolina during the Oligocene epoch has been identified by the scientists. The study of this skeleton says that based on the size it would’ve had large, tusk-like teeth and it was capable of feeding and hunting at high speeds like an orca.
The skeleton was found in 1990. It is the first nearly complete Ankylorhiza tiedemani skeleton to be analysed. The study of the skeleton has revealed that the two modern types of whales, toothed and baleen, evolved many of the same features in parallel independently of each other, rather than inheriting them from the same ancestor as previously thought.
The giant dolphin’s time as an ancient predator ended around 23 million years ago, when it became extinct. Since then, other whales and dolphins have taken turns, but today the only echolocating whale that’s also an apex predator is the orca. More Ankylorhiza fossils are awaiting study, and the researchers are hopeful that there are many more discoveries to be made.
The research was published in Current Biology.