Dirty mud-sucker!

Fossilized cetaceans provide for one of the more robust evolutionary records. Especially with whales, it is abundantly clear that it takes the fundamental underlying theme of all of biology – evolution – to explain all that pesky empirical evidence we have. Now some light has been shed on the origin of baleen.

The fossil whale, thought to be between 25 and 28 million years old, hints that mud sucking might have been a precursor to the filter feeding used by today’s baleen whales.

Many modern whale species use hair-like structures called baleen to filter tiny prey such as krill from seawater. Baleen species include the humpback, the minke, and the largest animal ever to have lived on Earth, the blue whale.

The newfound fossil whale, which measures just nine feet (three meters) long, shares the same distinct jaw and skull structures as today’s baleens.

But the tiny whale also had teeth, said study author Erich Fitzgerald, a paleontologist at Museum Victoria in Melbourne, Australia.