Scientists in Queensland (Australia) have uncovered part of a fossilised jawbone that suggests the rivers and lakes of ancient Australia may have been home to a super-sized crocodile that would not have looked out of place if it had lived at the time of the dinosaurs. The island of Australia has been isolated from other land masses for millions of years, this has permitted the fauna and flora to evolve without competition from other genera migrating into the country.
Marsupial mammals still dominate today and in the past Australia had its own, unique mega-fauna including cow-sized wombats, a giant monitor lizard called megalania and fearsome predators such as marsupial lions. The megafaunal assemblage of Australia survived into the Pleistocene, but the arrival of human settlers and climate change led to the extinction of most of these animals.
Scientists were aware that crocodiles had diversified and evolved into a myriad of different species. The discovery of a partial jawbone suggests that at least one type of crocodile evolved into a giant, perhaps a contender for the biggest crocodylian known from the fossil record. Australia is home to the Saltwater crocodile, otherwise known as the Estuarine crocodile (Crocodylus porosus), it is the largest species of reptile on the planet, with males reaching lengths in excess of seven metres and weighing more than a tonne.
It is often referred to as “Australia’s own dinosaur”, but like all Crocodylians, it is only very distantly related to the Dinosauria. University of New South Wales palaeontologists who found the fragment of crocodile jaw state that this individual was at least eight metres long and there may have been others of its kind that were even larger, perhaps reaching the size of Sarcosuchus, a twelve metre long Crocodylian that lived during the Late Cretaceous geological period and preyed on dinosaurs.
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