From why they use Viagra to why we once drank their urine, these panda facts reveal everything you never knew about nature's most mysterious bears.

Newborn cubs are blind, helpless, and only about the size of a stick of butter.Flickr (left), Flickr (right)

At 1/900th the size of its mother, a newborn panda is one of the smallest newborns, relative to its mother's size, on Earth.Flickr

Pandas can grow to be 2-3 feet tall at the shoulder, 4-6 feet in length, and up to 250 pounds.Flickr

While most people know that pandas eat bamboo (which accounts for 99% of their diet), they're definitely not strict vegetarians...Flickr

Whether eating small creatures or bamboo, pandas make use of the largest molars of any mammalian carnivore on earth.Flickr

Because of its extremely inefficient digestive system, an adult panda must spend 10-16 hours per day foraging and eating.Flickr

Uniquely, pandas eat while sitting upright, in a position resembling the way a human would sit on a floor.Pixabay

This seated position allows them to grasp bamboo, with the help of another unique adaptation, their "pseudo thumb," actually an elongated wrist bone.Flickr

Over the course of the 10-16 hours of eating each day, a panda will consume 20-40 pounds of bamboo.Flickr

Although they spend so much time resting and sleeping, pandas are relatively unique among bears in that they do not hibernate.Flickr

The giant panda first appeared toward the end of the Pliocene epoch, between 2 and 3 million years ago.Flickr

However, by most accounts, the Western world didn't become aware of pandas until the late 19th century.Flickr

The first Westerners given the "privilege" to hunt and kill a panda were two of Theodore Roosevelt's sons, Theodore Jr. and Kermit.Flickr

Some schools of traditional Eastern medicine claimed that drinking panda urine could melt accidentally swallowed needles.Flickr

Adult pandas are extraordinary loners, and use their keen sense of smell to avoid other pandas.Flickr

Because of its numerous differences from most other bears, the panda was long thought to actually be a closer relative of the raccoon.Flickr

Researchers don't know for sure why pandas have their distinctive black and white coat. Some speculate that it provides camouflage in their snowy and rocky habitat.Flickr

Due to dwindling habitats, there are less than 2,000 pandas left in the wild and only about 400 in captivity.Flickr

Without human intervention, pandas will become extinct.Animal Planet/Mark Orton

Panda populations recover slowly from decreases chiefly because females are only able to conceive on two or three days per year.Flickr

Furthermore, captive pandas exhibit great reluctance to mate. Scientists have shown pandas pornography and given them Viagra to combat this problem. Wikimedia Commons

Leading the fight against extinction, China's Bifengxia Panda Center has been safely breeding pandas in captivity since 2004.Flickr

Even more ambitiously, China's Wolong Panda Center is breeding and raising pandas for the expressed purpose of eventually releasing them into the wild.Flickr

Researchers at Wolong believe that pandas will be more easily introduced into the wild and less likely to gravitate toward humans if they're not used to seeing humans in normal human clothing. Thus, all who work with pandas there must wear panda suits.Animal Planet/Mark Orton

While the adult pandas at Wolong can see through the disguises and spot the humans, the cubs, by all accounts, cannot.Animal Planet/Mark Orton

Due in large part to the efforts at Wolong and Bifengxia, the world's total panda population has increased by 17% since 2003.Flickr
We adore pandas. We make special trips to a small number of select zoos just to see them. They're the face of the World Wildlife Fund. But how much do we really know about them?
We know they eat bamboo, but few people are aware of the rest of their surprising (and bloody) diet. We know they're black and white, but even the scientists researching them aren't entirely sure why. We know they're endangered, but you'd be amazed at the lengths conservationists have gone to, to get them to mate (panda porn, believe it or not, is a thing).
Discover more strange-but-illuminating panda facts above.
After checking out these panda facts, have a look at some elephant facts and shark facts that are guaranteed to blow your mind.