UC Davis Wildlife Biology Professor Tim Caro says it was challenging to solve the riddle of a panda's signature fur because no other mammal species looks anything like it. It made it difficult to draw scientific comparisons.
So Caro and fellow researchers at UC Davis and California State University, Long Beach found a different way to perceive the panda.
They focused on the head, the back and the legs as different “units” on the giant panda. And Caro says that shift allowed them to compare color blocks of panda fur with similar fur colors in other mammals.
“(At that point) we could start to make serious quantitative comparisons looking at what the different ecological and social factors might be associated with having a white back or black legs," explains Caro.
They looked at potential advantages of various fur colors, like temperature reduction and communication within and between species.
The researchers found a link between the panda’s black and white fur patterns and its need to travel to different habitats throughout the year to stay nourished.
Caro points out giant pandas have a diet made up exclusively of nutrient-poor bamboo. So, the mammals don’t store enough fat calories to spend the colder months in dormancy like their bear cousins. They’ve got to stay on the move and that means they live in strikingly different habitats.
Back to that striking black and white pattern. Caro and his collaborators found a panda's white backside helps it hide from predators in snowy terrain while black legs and shoulders provide camouflage in the shady sub-tropical forest.
“When you’re in kindergarten you learn about nature very early on by being shown that giant pandas are black and white and zebras are striped,” says Caro. “But,” he adds, “we’re never told why these animals are such beautiful colors.”
Caro says he hopes the story (and the science) behind the unique patterns of the panda's fur will draw children's curiosity, and perhaps inspire students to connect with the animal world up close.
(CSU Long Beach assistant professor Ted Stankowitch is co-author of the study which appears in the journal Behavioral Ecology.)