On the outside, giant pandas look like herbivores, largely sticking to a bamboo diet. But on the inside, they're built like carnivores. About half their calories come from protein, a study said, putting their diet on a par with wolves, feral cats and other animals that depend on meat to survive. A typical herbivore gets less than a quarter of its calories from protein.

Researchers found that pandas make the most of their vegetarian diet by following the protein. Between August and April, they ate Bashania fargesii leaves until they got the chance to feast on young shoots with more protein. When the shoots grew, and the protein became diluted by fiber, pandas moved to higher ground, where Fargesia qinlingensis grew. Again, they ate the shoots until these, too, went from being protein-rich to fiber-rich. The pandas then switched to the leaves before walking back down the mountain to resume the cycle.

Flowering plant seems to remember

Nasa poissoniana, a star-shaped flowering plant from the Peruvian Andes, can wave around their stamens — the organs they use for fertilization — to maximize the distribution of their pollen. More surprisingly, a study published in Plant Signaling and Behavior suggests that individual plants can adjust the timing of these movements based on their experiences with pollinators. In other words, they remember the past, and try to repeat it. The study "presents a promising and intriguing new system to study plant memory," said Peter Crisp, a plant geneticist at the University of Minnesota who was not involved in the study.

New sources of flaming mountains

Atop a mountain in Turkey, the ground spits fire, flames that have burned for millenniums. The source for the Flames of Chimaera is gas escaping from deep within Earth — not from the decay of ancient plant or animal life, but from a chemical reaction inside rocks. And it's more common than thought. A group of scientists known as the Deep Carbon Observatory reported that it has found hundreds of similar gas deposits in more than 20 countries.