Australian fossil unlocks secrets to the origin of whales

December 21, 2009

Museum Victoria palaeobiologist Dr Erich Fitzgerald has made new groundbreaking discoveries into the origin of baleen whales, based on a 25 million year old fossil found near Torquay in Victoria.

Dr Fitzgerald's study, which is published in the Zoological Journal of the Linnean Society, is centred on Mammalodon colliveri, a primitive toothed baleen whale, one of a group of whales that includes the largest animal ever to have lived, the blue whale. Although Mammalodon was discovered in 1932 and named in 1939, it has remained relatively unknown until now.

"Through study of Mammalodon, I hypothesise that it was a bottom-feeding mud-sucker that may have used its tongue and short, blunt snout to suck small prey from sand and mud on the seafloor. This indicates early and varied experimentation in the evolution of baleen whales", explained Dr Fitzgerald.

The research conducted by Dr Fitzgerald supports Charles Darwin's speculation in The Origin of Species, that some of the earliest baleen whales may have been suction feeders, and that their mud grubbing served as a precursor to the filter feeding of today's giants of the deep.

Although Mammalodon had a total body length of about 3 metres, it was a bizarre early offshoot from the lineage leading to the 30 metre long blue whale. The new research shows that Mammalodon is a dwarf, having evolved into a relatively tiny form from larger ancestors.

Mammalodon belongs to the same family as Janjucetus hunderi, fossils of which were also found in 25 million year old Oligocene rocks near Torquay in Victoria. This family is unique to south east Australia, their fossils only being discovered in Victoria. "Clearly the seas off southern Australia were a cradle for the evolution of a variety of tiny, weird whales that seem to have lived nowhere else", said Dr Fitzgerald.
-end-
Dr Erich Fitzgerald is a palaeobiologist specializing in the evolution of marine mammals. Having recently returned from the USA, where he held a Postdoctoral Fellowship at the Smithsonian Institution, Erich is now the Harold Mitchell Fellow at Museum Victoria in Melbourne. Erich also holds honorary appointments at the Smithsonian Institution and Monash University. This research is a result of five years of study across Monash University, the Smithsonian Institution and Museum Victoria.

Fossils from Mammalodon colliveri will go on display in the foyer of Melbourne Museum from December 22.

Dr Erich Fitzgerald's paper will be available online from December 22 at http://doi.wiley.com/10.1111/j.1096-3642.2009.00572.x

Melbourne Museum
Nicholson Street, Carlton
Adults $8, children and concession card holders FREE
Ph 13 11 02 or visit museumvictoria.com.au

Wiley

Related Evolution Articles from Brightsurf:

Seeing evolution happening before your eyes
Researchers from the European Molecular Biology Laboratory in Heidelberg established an automated pipeline to create mutations in genomic enhancers that let them watch evolution unfold before their eyes.

A timeline on the evolution of reptiles
A statistical analysis of that vast database is helping scientists better understand the evolution of these cold-blooded vertebrates by contradicting a widely held theory that major transitions in evolution always happened in big, quick (geologically speaking) bursts, triggered by major environmental shifts.

Looking at evolution's genealogy from home
Evolution leaves its traces in particular in genomes. A team headed by Dr.

How boundaries become bridges in evolution
The mechanisms that make organisms locally fit and those responsible for change are distinct and occur sequentially in evolution.

Genome evolution goes digital
Dr. Alan Herbert from InsideOutBio describes ground-breaking research in a paper published online by Royal Society Open Science.

Paleontology: Experiments in evolution
A new find from Patagonia sheds light on the evolution of large predatory dinosaurs.

A window into evolution
The C4 cycle supercharges photosynthesis and evolved independently more than 62 times.

Is evolution predictable?
An international team of scientists working with Heliconius butterflies at the Smithsonian Tropical Research Institute (STRI) in Panama was faced with a mystery: how do pairs of unrelated butterflies from Peru to Costa Rica evolve nearly the same wing-color patterns over and over again?

Predicting evolution
A new method of 're-barcoding' DNA allows scientists to track rapid evolution in yeast.

Insect evolution: Insect evolution
Scientists at Ludwig-Maximilians-Universitaet (LMU) in Munich have shown that the incidence of midge and fly larvae in amber is far higher than previously thought.

Read More: Evolution News and Evolution Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.