A group of scientists in China studied the metabolic pattern of pandas, in relation to their food source, and what they found was that pandas aren't like typical herbivores.

Their gut bacteria is actually not capable of properly digesting their steady diets of bamboo and, in fact, pandas are more similar to their cousins, omnivorous mammals like the black bear.

For the study, the team analyzed 121 fecal samples of 45 panda bears. Twenty-four of the pandas were adults, while 16 were juveniles and five were cubs. Like previous studies of wild pandas, this new study showed that there was an absence of both Ruminococcaceae and Bacteroides, which are plant-degrading bacteria, in the guts of the bears.

"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," coauthor of the study Xiaoyan Pang says.

Taken together, other studies along with the new analysis underscore the giant panda's place as a bear in the animal kingdom says Mike Maslanka, head of the nutrition science department at the Smithsonian's National Zoo in Washington, D.C.

"Regardless of their diet, giant pandas are bears. They're cool and fuzzy, black and white, but they're bears," says Maslanka, who was not involved in the study. "It just reinforces that, from the inside out."

So how do pandas continue to survive when their guts are not suited to digest their favorite meals? It's simple. They stuff themselves.

"Let's say their GI tracts had these microorganisms. Maybe we would only have to feed them a quarter of what they're eating now. But because they don't have that mechanism, to compensate they eat a whole bunch," Maslanka says. "They essentially adapted to a very poorly digestible diet, and they do it well."

Giant pandas are endangered and on the brink of extinction, but now that scientists understand how their guts actually work, scientists hope that by giving them probiotics or even bacteriotherapy they could one day help them better adapt to their environments and better survive when food is scarce. 

Currently, for example, pandas in zoos are given anywhere from 50 to 100 pounds of bamboo a day. Using these therapies, pandas could reduce their reliance on such vast quantities of bamboo, which would better equip them to survive in the wild when their favorite food may not be so abundant.