toothless rat
August 23, 2012

New Rat Species Unable To Chew And Gnaw

Lee Rannals for — Your Universe Online

Imagine a rodent that doesn't come out of a U-shaped hole in your wall to eat cheese, simply because it is unable to craft such a home. Well, a new species of rat lives up to that thought.

A species of near-toothless rat was found in Indonesia, living off earthworms and spending its time sucking and slurping instead of chewing or gnawing.

The animal, paucidentomys vermidax, is the only rodent scientists have found out of the 2,200 known species that does not have molars, but instead has bicuspid upper incisors.

“The specialized incisors of rodents give them the distinct ability to gnaw - a defining characteristic of rodents worldwide. In having lost all teeth except a pair of unusually shaped incisors that are incapable of gnawing, this new rat is unique among rodents,” Mr. Anang Achmadi, Curator of Mammals at Museum Zoologicum Bogoriense, said in a press release.

Two rats were found in the mountainous rain forset of southern Sulawesi Island last year on Mount Latimojong, and 62 miles northwest on Mount Gandangdewata.

The rat uses its long snout to suck out earthworms, and then slices them with its incisors before spitting out pieces and slurping up bites, according to Anang Achmadi from Indonesia's Museum Zoologicum Bogoriense.

The scientists who reported the find in the journal Biology Letters said the discovery is important because it shows how rodents were forced to evolve to survive in Sulawesi's environment.

“This is an example of how species, when faced with a new ecological opportunity, in this case an abundance of earthworms, can evolve the loss of traits that were wildly successful in previous circumstances,” co-author Kevin Rowe, senior curator of mammals at Museum Victoria in Melbourne, Australia, said in a press release.

“In the mountains of Sulawesi, where we discovered Paucidentomys, healthy forests still nurture rare and remarkable species, however, they are isolated patches imperiled by expanding logging, mining, plantations and other human activities.”

The paucidentomys vermidax, which stands for few-toothed mouse" and essentially "worm eater," is not completely out of the norm when it comes to being a rodent. The researchers said that it has a rat-like tail.

“While we face a global crisis of biodiversity loss, this new species reminds us that we are still in an age of biodiversity discovery. Wild habitats where new species wait to be discovered are still out there,” Dr. Rowe said in a statement.