From watching Planet Earth, I learned a few things about giant pandas which make me question how the animal is still in existence: 

1. A panda's diet consists almost entirely of bamboo shoots, which provide little nutritional benefit.  For that reason, pandas don't hibernate; they wouldn't survive long without a belly full of nutrition-less bamboo.
2. "Because of the synchronous flowering, death, and regeneration of all bamboo within a species, pandas must have at least two different species available in their range to avoid starvation." (from wiki)
3. Because of increased temperatures in their normal habitat, pandas have moved to higher elevations, where less species of bamboo are available, thus further limiting their food sources.
4. Baby pandas are born completely helpless and defenseless, so they require the mother's undivided attention.  If a mother gives birth to more than one baby, she only has time to care for one, so she'll let the other one(s) die.
5. "Breeders and biologists often experience difficulty in inducing captive pandas to mate." (from wiki)

All in all, pandas seem to lack any type of "survival of the fittest" instinct.  Poor pandas. #nature