Chimpanzees Like to Sleep on Beds Made of Sturdy Ugandan Ironwood, Researchers Find

Researchers have found that Chimpanzees like to sleep on beds made of Ugandan Ironwood.  

The study on Chimpanzee sleeping habits was conducted by researchers at University of Nevada Indiana University. The team found that the Ugandan Ironwood is tough and provides the chimpanzees a stable, firm bed.

 The research also advances the idea that good sleep was linked to primates evolving into humans, National Geographic reported

It is known that chimpanzees are choosy about the wood that they use to make beds (called nests). However, scientists wanted to know why they preferred one kind of tree over others.

For the study, researchers analyzed physical characteristics of tree species found in Toro-Semliki Wildlife Reserve, Uganda. They looked at stiffness of tree branches and leaf surface area of trees commonly used by chimpanzees. In all, 1,844 chimpanzee nests were studied.

Even though the Ugandan Ironwood makes up just 9.6 percent of all trees in the sample area, it accounted for 73.6 percent of all Chimpanzee nests.

"Despite the fact it's relatively rare, they're saying seven out of ten times, 'I want to sleep in this species,'" David Samson from the University of Nevada, one of the study authors, told The National Geographic.

The team found that Ugandan Ironwood was the stiffest among all trees sampled in the area. Also, the tree had the least distance between leaves and branches.

"Chimpanzees, like humans, are highly selective when it comes to where they sleep. This suggests that for apes there is something inherently attractive about a comfortable bed--down to what kind of wood you use to make it," Samson said in a news release.

Samson and team want to know whether or not unique sleeping habits of great Apes (including humans) are linked to higher intelligence.

According to the National Geographic, only higher apes are known to make beds using branches from specific trees.

Science has shown that there is a link between a good night's sleep and cognitive function. So, traits that allow for longer sleep duration might be connected with better-functioning brains.

The study is published in the journal PLOS One.