Mega rodents: Researchers discover largest rat species

They've found the fossils of seven giant rat species on East Timor, with the largest up to 10 times the size of modern rats.

"They are what you would call mega-fauna", Julien Louys, a researcher with Australian National University, said in a news release.

They weighed as much as a modern miniature dachshund or Boston terrier. The terrifying scenario could become a reality as super-adaptable rats take advantage of larger mammals becoming extinct, an expert predicted previous year.

Evidences suggest that on East Timor humans were living around 46,000 years ago while the oldest evidence of giant rats dates back to 44,000 years ago, suggesting humans were coexisting with the enormous rodents and hunted and ate them regularly.

Getty You dirty rodent Retro rats made modern ones look positively loveable

The researchers hope to gain insight into human movement through the region during the time of the giant rats' existence, and the effects that human activity may have had on local ecosystems.

"We know they're eating the giant rats because we have found bones with cut and burn marks", Dr Louys says.

Humans and large rats co-existed in East Timor for a thousands of years until the rats became extinct. Now researchers are looking into what may have caused these dog-sized rats to die out (but for real, let's just be glad that they're not scurrying around anymore). They believe this information could help guide today's conservation efforts.

"We're trying to find the earliest human records as well as what was there before humans arrived", said Louys.

Louys, who returned from East Timor in August, presented his findings at the Meetings of the Society of Vertebrate Palaeontology in Texas.

The project forms part of Sue O'Connor's ARC Laureate 'From Sunda to Sahul: Understanding Modern Human Dispersal, Adaptation and Behaviour en route to Australia'.

'Animals will evolve, over time, into whatever designs will enable them to survive and to produce offspring, ' said geologist Dr Jan Zalasiewicz, from the University of Leicester. These specimens represent the largest known rats to have ever existed, according to a news release.

Julien and his team blamed human intervention along with tough competition with predators like monitor lizards and large birds were responsible for the extinction of these species.