The discovery of a bizarre species of fossil whale from Australia with huge eyes and flesh-ripping jaws provides valuable new insights into the evolution of whales, researchers say.
The previously unknown species lived about 25 million years ago and was an early ancestor of modern baleen whales, which feed by filtering plankton from seawater. This group includes the blue whale, the largest animal ever to inhabit the planet.
But the newfound predatory whale likely hunted sharks and other fish despite its relatively small size and suggests that baleen whales weren't always the toothless gentle giants we see in our oceans today.
The new species, Janjucetus hunderi, had a maximum body length of about 11.5 feet (3.5 meters) and sharp, serrated teeth measuring up to 1.4 inches (3.5 centimeters) long.
Discovered in cliffs on a surfing beach near Torquay in southeast Australia, the prehistoric whale is described in the latest issue of the journal Proceedings of the Royal Society B.
Scientists identified the new species as a baleen whale from distinctive skull features.
No Gentle Giant
The author of the study—paleontologist Erich Fitzgerald from Monash University in Clayton, Australia—says the weird sea mammal shows that the earliest baleen whales were surprisingly unlike their living relatives in appearance and lifestyle.
He says the fossil also forces a major rethinking of how modern baleen whales evolved their unique feeding system.
These whales use long, hair-fringed, flexible plates called baleen to filter huge quantities of seawater, capturing thousands of planktonic animals such as krill in a single mouthful.
(Related story: "Rare Whales Can Live to Nearly 200, Eye Tissue Reveals" [July 13, 2006].)
"It is most likely that Janjucetus preyed upon large fish, and maybe even some of the smaller sharks that cruised the seas off southern Australia 25 million years ago," Fitzgerald said.
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