My, what big teeth you have

Not long ago, an Australian citizen scientist found buried in a boulder the rare fossilised remains of a mammoth prehistoric shark — providing the first evidence that this predator once swam in Australian waters.

The discovery was made by Philip Mullaly on a beach at Jan Juc in the Australian state of Victoria. The seven-centimetre-long teeth were identified as belonging to an extinct species of mega-toothed shark, Carcharocles angustidens, the Great Jagged Narrow-Toothed Shark.

C. angustidens, which lived during the Oligocene epoch, nearly 25 million years ago, was first identified in 1835 by Swiss naturalist Louis Agassiz. Subsequent fossil evidence allowed scientists to estimate the creature grew up to nine metres long, one-and-a-half times the length of today’s Great White Shark. 

Mullaly’s internationally significant finding — which marks only the third time multiple teeth of this species have been found — was handed over to palaeontologist Erich Fitzgerald of Museums Victoria. 

This led Fitzgerald and his team to carry out subsequent excavations of the site. They found more than 40 teeth belonging to another small species known as the Sixgill Shark (from the genus Hexanchus). These would have scavenged on the carcass of the mega-tooth, sloughing off their teeth and leaving them to fossilise by its remains. 

The public can view this collection as part of The Mega Shark Fossil Find display, at Melbourne Museum in the suburb of Carlton, starting August 9. If you would like to hear more about this and other paleontological wonders, Fitzgerald and his colleague Tom Rich will speak at the museum on August 19.