Climate change and whale evolution

30 September, 2009

Dr Erich Fitzgerald with three extinct whale skulls.
Dr Erich Fitzgerald with three extinct whale skulls.
Image: Nicole Alley
Source: Museum Victoria

Museum Victoria welcomes back Dr Erich Fitzgerald, who has returned from a year at the Smithsonian Institution to take up the Harold Mitchell Fellowship.

Erich completed his PhD on the palaeobiology of ancient baleen whales in 2008. He is a familiar face around the museum, having worked as a research associate in the palaeontology department for several years. In 2006 he described the extraordinary extinct whale Janjucetus hunderi from a 25 million-year-old fossil skull uncovered at Jan Juc.

Modern baleen whales, such as Humpback Whales and Blue Whales, have no teeth as adults. Instead, they filter small prey such as krill with comb-like plates in their mouths called baleen. Janjucetus belongs to the same group as baleen whales, but instead of baleen it had ferocious teeth for hunting large prey. Thus, it dates from before the evolution of baleen and had a completely different way of life to its modern-day relatives.

Erich’s new research will build upon his work with Janjucetus to link the impact of past environmental changes on the evolution of marine mammals. This three-year project is supported by the Harold Mitchell Fellowship, which honours former Museum Victoria Board president, Harold Mitchell AO, and targets the unique insights that palaeontology can provide about the effect of long-term climate change on biodiversity.

Working with the museum’s palaeontology and mammal collection, Erich will reconstruct how the marine mammals of southern Australia responded as the global climate changed and Australia drifted northward after separating from Antarctica. “About 95 per cent of the fossil record of marine mammals in this part of the world is locked up in the vaults of Museum Victoria, so it’s a fantastic resource,” said Erich.

He will continue field work at the 25-million-year-old rock formation near Torquay that has already yielded Janjucetus and a wealth of sharks, fishes, shells and corals – traces of ecosystems of the past. But to examine change, comparison with other eras – older, younger and contemporary –  is critical. “Five million years ago, Port Philip Bay hosted an incredible ecosystem quite unlike what we see today,” he continued, “and it is all here in the fossil record.”

“Within metropolitan Melbourne, we have the richest assemblage of five-million- year-old marine critters yet discovered in Australia.” Among the extinct wonders of the area are seals, giant penguins, sharks the size of a whale and even dugongs. Erich’s research will help us understand how such an incredible biodiversity came to be and why it declined.

He will also revisit his old friend Janjucetus and re-examine the fossil in the light of new data. He expects further surprises. “The book is not yet closed on Janjucetus. It’s only revealed some of its secrets.”

Comments (1)

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Albert Hertaeg 25 November, 2013 21:39
We found a fossil tooth at Janjuc a while back. Its about 5cm long. Could it be from a janjucetus!! Thought it was a shark tooth at the time. Its at home in Switzerland at the moment and could send a picture when I get back if you want.
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