Australian fossil find changes whales' evolutionary history

Australian researchers have found evidence that modern baleen whales - now docile filter-feeders - derived from a beast with razor sharp teeth and ferocious eating habits.

The findings are based on research of a 25-million year old fossil skull uncovered among cliffs in Southern Australia. The specimen, called Janjucetus hunderi was unveiled at the Melbourne Museum this week.

Caught up in a different crowd
In the past, scientists divided whale ancestors into two groups.

One group is made up of the filter fed whales which evolved into their modern filter feeders like the baleen whale.

The other group included whales that hunted and evolved into toothed species like the dolphin, sperm whale, and killer whale.

This new research, conducted by Monash University researcher and Victoria Museum research associate Erich Fitzgerald, suggests that the ancestor of the baleen whale may have been classified with their hunting relatives.

A change of diet
Modern-day baleen whales usually feed with a comb-like structure between their jaws, which filters out plankton and small fish.

But the ancient species, the research shows, had large teeth to help capture and chew their prey, which included sharks and other large fish.

Fitzgerald found distinctive features in the species' skull to classify it as an ancestor of the baleen whale.

The ancient species also had particularly large eyes, which the researchers suggest may have helped its hunting habits.

The study appeared in a recent edition in Proceeding of the Royal Society B.

Photography: Futura Sciences

Source: Discovery Channel Reports, August 19 edition