Upper toothrows of Timor's extinct giant rat (left), the biggest rat that ever lived, compared with the skull of a black rat (right). Archaeological research in East Timor in 2010 unearthed the bones of the biggest rat that ever lived, with a body weight around 6 kg. The cave excavations also yielded a total of 13 species of rodents, 11 of which are new to science. Eight of the rats weighed a kilogram or more. Carbon dating shows that the biggest rat that ever lived survived until around 1000 to 2000 years ago, along with most of the other Timorese rodents found during the excavation. Only one of the smaller species found is known to survive on Timor today.