Why are giant pandas black and white?
The giant panda's graphic pattern has stumped biologists for years ... now they have an answer.
Mother Nature is nothing if not clever, especially as evidenced in the beautiful ways that organisms evolve. Take the zebra and its stripes. Why does a zebra have stripes? As it turns out, the stripes help deter biting flies like horseflies and tsetse flies. Genius!
Most often, animals and their colors or patterns make sense – there’s not much mystery behind why an Arctic fox is white. But where does the beloved giant panda fit into this scheme? Aside from turning grown-ups into cooing blubbering mushes, what purpose do those cartoon-animal black and white patches serve?
This was the question put forth in a study by scientists from the University of California, Davis, and California State University, Long Beach, who determined that the giant panda's distinct black-and-white markings have two functions: camouflage and communication.
"Understanding why the giant panda has such striking coloration has been a long-standing problem in biology that has been difficult to tackle because virtually no other mammal has this appearance, making analogies difficult," says lead author Tim Caro from the UC Davis Department of Wildlife, Fish and Conservation Biology. "The breakthrough in the study was treating each part of the body as an independent area."
The team compared the giant panda’s different areas of fur with the dark and light coloring of 195 other carnivore species and 39 bear subspecies. With that, they matched the dark regions to various ecological and behavioral variables to determine their function.
What they found is that the panda’s face, neck, belly, and rump – the white parts – help it hide in snowy habitats. Well that makes sense, but what about the bold back parts? They help it hide in the shade.
What’s fascinating is that the giant panda requires this convertible camouflage in the first place – for which we can thank the bear’s taste for bamboo. Since giant pandas are unable to digest a wide variety of plants, they’re stuck with bamboo. Bamboo is a relatively poor food source that doesn’t allow for the storage of enough fat for the pandas to go dormant during the winter like other of their bear brethren do. Instead, the panda is active year-round and traverses many miles and habitat types, from snowy mountains to tropical forests.
Which still doesn’t account for those giant panda giant eyes. We swoon for those panda faces because of “neoteny” – the retention of juvenile features (big eyes, big head, roly-poly demeanor), which we are programmed to adore. But since giant pandas’ survival isn't dependent on making humans go weak in the knees, the team looked further into the function of the markings on the head.
They concluded that the marking are used to communicate. “Dark ears may help convey a sense of ferocity, a warning to predators,” the study notes. “Their dark eye patches may help them recognize each other or signal aggression toward panda competitors.”
© Ricky Patel
"This really was a Herculean effort by our team, finding and scoring thousands of images and scoring more than 10 areas per picture from over 20 possible colors," says co-author Ted Stankowich, a professor at CSU Long Beach. "Sometimes it takes hundreds of hours of hard work to answer what seems like the simplest of questions: Why is the panda black and white?"