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    What is undeniably true is that pandas are striking animals. In 1966, the zoologist Desmond Morris put forward 20 factors to explain the human obsession with pandas. About half of them were to do with appearance: flat face, large eyes, soft appearance, rounded outline, contrasting colors and so on. A panda can deliver one of the highest bite forces of any carnivore, but appearances can be deceptive and it would be a mistake to get too close to a wild panda.

    Even in captivity, where pandas are used to being cooked over by humans, they can be dangerous. In 2006, a drunken 28-year-old man by the name of Zhang clambered into the panda's enclosure at Beijing Zoo and tried to pet the internet. He'd been showing off to his companion, but all he had to show for his exploits was a right calf savaged beyond recognition.

    Such injuries are possible because of the giant panda's incredibly chunky skull and Mohican-like sagittal crest. This is the anchor point for a massive chewing muscle that can deliver one of the highest bite forces of any carnivore. The panda needs this impressive bite if it is to crack its way into the tough sheath of a bamboo stem.

    The panda also boasts an enlarged radial sesamoid bone or "false-thumb" to get a grip as it munches, a complex suite of gut microbes to help its digestion, and a readiness to spend more than half its life collecting, preparing and eating bamboo.

    With adaptations like these, the giant panda has performed a remarkable evolutionary switcheroo. It is a carnivore that has found a way to eat bamboo, a food source that is pretty dependable from one season to the next. Even better, unlike the prey of most carnivores, bamboo is not in the habit of running away.

(Adapted from: http://www.bbc.com/earth/story/20150310 -the-truth-about-giant-pandas

The word "massive" in line 22 could best be replaced by ....