A Rodent Without Molar

A peculiar rodent without molars grabbed the attention of the researchers from McMaster University in Ontario, Canada. This unique shrew like animal with a long pointed snout was found in Indonesia's forests of southern Sulawesi Island.  Its study is being published in the journal Biology Letters. 

Paucidentomys vermidaxt stands out of the known 2,200 species and has bicuspid upper incisors instead of molars.

LiveScience quoted Jacob Esselstyn, a postdoctoral researcher in biology at McMaster University in Ontario, Canada, "When we caught the animal, we were in the forest, and we knew right away that it was something different. But we couldn't see inside of its mouth, so had no idea of the unusual lack of teeth. The rats live in wet, mossy forests at high elevation. It's not yet clear how common they are, though they do seem difficult to trap. One of the rats had a stomach full of worm segments and nothing else, suggesting that the rodents eat mostly or only earthworms."

According to Discovery Magazine, Esselstyn thinks that the rat has lost the ability to chew and gnaw because it only eats soft prey. Its teeth are used for capturing food rather than processing it.

Dr Anang Achmadi, curator of mammals at Indonesia's Museum of Zoology in Bogor told Dailymail, "the specialized incisors of rodents give them the distinct ability to gnaw - a defining characteristic of rodents worldwide."

"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," informed Dr Kevin Rowe from Museum Victoria in Australia, a member of the discovery team.

The presence of rat's tail, long thin nose indicates that it shares some characteristics with shrew rats from the Philippines. But it is the lack of chewing molars that differentiates it.

Like the lost limbs of snakes and whales, this new discovery throws light on the fact that species evolve in order to withstand the changing and challenging dynamic environments.