Despite the important role of understory plants in forest ecosystems, climate impact assessments on understory plants and their role in supporting wildlife habitat are scarce in the literature.

That’s part of an abstract in a new paper in Nature Climate Change. A group of researchers at Michigan State University and the Chinese Academy of Sciences decided to look at the future of a few bamboo species under different climate change models.

The scientists studied bamboo species that carpet the forest floors of prime panda habitat in northwestern China. Unlike some of the more common, fast growing-species, the bamboo species that serve as understory in the Qinling Mountains only flower and reproduce every 30 to 35 years, which limits the plants’ ability to adapt to changing climate and can spell disaster for a food supply and more.

These mountains are home to about 275 wild pandas, or 17 percent of the remaining wild population. Bamboo makes up 99% of the giant pandas’ diet. Sadly, even under the most optimistic climate change scenario, bamboo die-offs would effectively cause this prime panda habitat to become inhospitable by the end of the 21st century.

The scientists are aware of how important the pandas are in telling this story. “The giant panda is a special species,” says lead researcher Mao-Ning Tuanmu. “People put a lot of conservation resources into them compared with other species. We want to provide data to guide that wisely.”

But the pandas are only a part of the story. Bamboo is a vital part of forest ecosystems—providing essential food and shelter for other wildlife, including other endangered species like the ploughshare tortoise and purple-winged ground-dove. It’s all interconnected. From Science News:

Scientists need to pay more attention, the team writes, to how changes in one part of the ecosystem (like bamboo) affect others within the same ecosystem (like pandas).

Image: MSU

The animals are built like carnivores, too. A genomic study on the wild panda in 2009 proved that that the bears have none of the features that other herbivores (like cows) have to breakdown the tough cellulose fibers of bamboo.

In fact, of the 12.5 kg (27.5 lbs) of bamboo the pandas eat in a day, they’re only able to digest about 17% of it. According to National Geographic News:

This explains why pandas also evolved a sluggish, energy-conserving lifestyle.

Scientists from the Chinese Academy of Sciences decided to look at the microorganisms that live in the guts of these bears. So they grabbed some panda poop, or, rather, stool samples from seven wild pandas and eight captive pandas. (Their diets vary a bit.)

Analyzing the samples, the researchers found 13 different types of Clostridium-related bacteria, known to breakdown cellulose. Of those, seven were unique to the pandas compared to other mammals. The researchers conclude that these microbes allow the panda to gain extra energy from the bamboo stalks.

Nature News describes this extraordinary feat in context:

These microbes are part of a suite of evolutionary adaptations — alongside powerful jaws and teeth, and pseudo-thumbs, bones that allow them to grip plant stalks — that help pandas to live on bamboo, despite having a carnivore’s digestive system.

The new research is published in this week’s Proceedings of the National Academy of Sciences.

Image: Mfield, Matthew Field/Wikipedia