Shedding light on the origin of the baleen whale

Date: November 30, 2016

Source: Monash University

Monash University scientists have played a key role in discovering the origin of filter feeding in baleen whales -- the largest animal known to have ever existed.

The discovery is detailed in a paper co-written with international researchers and palaeontologists from Museum Victoria. 'Alfred' the 25- million-year-old fossilised whale skull was unveiled at the Museum today.

"Alfred shows how ancient baleen whales made the evolutionary switch from biting prey with teeth to filtering using baleen," said Monash Science Senior Research Fellow, Dr Alistair Evans, one of the authors of the paper.

"They first became suction feeders. Feeding in this way resulted in reduced need for teeth, so over time their teeth were lost before baleen appeared."

There has been a lot of mystery around how and when baleen first formed.

"But we now have long-sought evidence of how whales evolved from having teeth to hair-like baleen -- triggering the rise of the biggest beasts on the planet," said Dr Evans. Nick-named 'Alfred', the fossil skull is from an extinct group of whales called aetiocetids, which despite having teeth were an early branch of the baleen whale family tree.

Alfred's teeth show exceptionally rare evidence of feeding behaviour suggesting an entirely new evolutionary scenario -- before losing teeth and evolving baleen, these whales used suction to catch prey.

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