More Hibernating Lemurs Found In Madagascar [VIDEO]

Plenty of animals go into hibernation each winter, but until recently the only known primate to hibernate was Madagascar's western fat-tailed dwarf lemur.

But it turns out there are more languishing lemurs that we thought.

Scientists at Duke University report two other lemur species that go into hibernation when they burrow into the soft rain forest floor in the eastern part of Madagascar, curling up for three to seven months of underground snoozing.

In eastern Madagascar little-known lemurs -- Crossley's dwarf lemur and Sibree's dwarf lemur - are being studied by scientists who hope to gain new information on what sends hibernating animals into standby mode, and whether lemurs -- our closest genetic relatives known to hibernate -- do it differently from other hibernating animals.

"Exactly what triggers hibernation is still an open question," said lead author Marina Blanco a postdoctoral researcher at the Duke Lemur Center, according to a statement.

While bears, squirrels and other animals hibernate to survive the cold winter, lemurs in western Madagascar apparently hibernate to survive the during Madagascar's long dry season, a time when temperatures top 85 degrees F, trees drop their leafs and food and water supplies are scarce.

But the hibernation habits of eastern dwarf lemurs are of interest to the researchers because the lemurs there are exposed to winter temperatures that occasionally drop below freezing in the high-altitude forests where they make their homes.

"It's a very different environment," Blanco said.

To the untrained eye, the hibernating lemurs may appear to be dead.

"Their bodies are cold, they are utterly still and they take a breath only once every several minutes or so," said co-author Anne Yoder, director of the Duke Lemur Center.

The study "Underground Hibernation in a Primate," appears in the journal Scientific Reports.