Giant Pandas Poop All Day Because They Can't Digest Bamboos

Giant pandas have been eating bamboo for about 2 million years now, but they are horrible at digesting it, according to a new study.

Researchers studied the gut microbiome of the giant-bacteria, and found that the animals have relatively few bacteria that help digest fibrous plants such as bamboo.

Interestingly, researchers found that most of panda's gut is covered with bacteria that are typically found in meat eaters, according to researchers.

Evolution of giant panda might explain this behavior, as researchers noted that from bears that ate both plants and meat. Ancient giant pandas likely began eating bamboo about 7 million years ago but became exclusive bamboo eaters about 2 million years ago, the researchers added.

Modern pandas spend about 14 hours a day eating bamboo and yet it isn't easy for them digest it.

"Unlike other plant-eating animals that have successfully evolved anatomically specialized digestive systemsto efficiently deconstruct fibrous plant matter, the giant panda still retains a gastrointestinal tract typical of carnivores," Zhihe Zhang, the study's lead author and director of the Chengdu Research Base of Giant Panda Breeding in China, said in a statement.

"The animals also do not have the genes for plant-digesting enzymes in their own genome," Zhang said. "This combined scenario may have increased their risk for extinction."

Researchers did a genetic analysis of the gut bacteria in the poop of 45 healthy pandas residing at the Chengdu Research Base.

"This result is unexpected and quite interesting, because it implies the giant panda's gut microbiota may not have well adapted to its unique diet, and places pandas at an evolutionary dilemma," said study co-author Xiaoyan Pang, an associate professor in the School of Life Sciences and Biotechnology at Shanghai Jiao Tong University in China.

Researchers published their findings in the journal mBio.