Fossils reveal new species of extinct mammals

Ancient mammal remains digested by crocodiles have revealed new species of extinct creatures.

The fossilised bones, that appear to have been digested by crocodiles in the Cayman Islands, have uncovered three new species and subspecies of mammal that roamed the island more than 300 years ago.

A team led by the Zoological Society of London (ZSL), the American Museum of Natural History, and the New Mexico Museum of Natural History studied the bones from collections in British and American museums.

The bones had been previously collected from caves, sinkholes and peat deposits on the Cayman Islands between the 1930s and 1990s.

Published in the Bulletin of the American Museum of Natural History, the team describe two new large rodents (Capromys pilorides lewisi and Geocapromys caymanensis), as well as a small shrew-like mammal named Nesophontes hemicingulus.

Fossil remains of the land mammal have been previously reported from the Cayman Islands, but have not been scientifically described until now.

The three mammals were unique to the Cayman Islands, existing nowhere else in the world.

The scientists calculated that they would have probably become extinct around the 1700s, likely due to the arrival of European settlers and introduced mammals such as rats, cats and dogs.

Animals described as “coneys” and “little beasts like cats”, which were probably the now-extinct rodents Capromys or Geocapromys, were seen and recorded by Sir Francis Drake when he visited the Cayman Islands in 1586, the ZSL said.

Professor Samuel Turvey, senior research fellow at ZSL’s Institute of Zoology, and co-author of the paper, said: “Humans are almost certainly to blame for the extinction of these newly described mammals, and this represents just the tip of the iceberg for mammal extinctions in the Caribbean.

“Nearly all the mammal species that used to live on these tropical islands, including all of the native Caribbean sloths and monkeys, have recently disappeared.

“It’s vitally important to understand the factors responsible for past extinctions of island species, as many threatened species today are found on islands.

“The handful of Caribbean mammals that still exist today are the last survivors of a unique vanished world and represent some of the world’s top conservation priorities.”