Giant dog-sized rat bones found in Australia
The rats, detailed in the Bulletin of the American Museum of Natural History this week, were thought to be around 13 pounds, three times the size of the largest living species.
Ken Aplin, of Australia's Commonwealth Scientific and Industrial Research Organisation, told AFP the rats lived in East Timor until 1,000 to 2,000 years ago, and were likely wiped out by changes in agricultural practices and habitat clearance.
"Large-scale clearing of forest for agriculture probably caused the extinctions, and this may have only been possible following the introduction of metal tools," Aplin said.
The largest living rats weigh around 4 pounds and live in rainforests in the Philippines and Papua New Guinea.