It’s hard to find someone who is not charmed by the entertaining antics of a roly-poly panda bear. Being one of only four zoos in the United States to exhibit pandas, the San Diego Zoo certainly sees its fair share of panda fans. Guests love watching the cute black-and-white bears munch on bamboo, roll through bark chips, or do handstands against a tree. Although these behaviors are enthralling and endearing, scientists believe they may also be serving as an essential means of communication between the bears.
The most distinguishing feature of a panda is their black-and-white fur. The fur keeps them warm during the snowy mountainous winters of Sichuan, and scientists believe that the black-and-white coat may provide some camouflage in the shadowy bamboo forests where pandas are found. Because these bears are solitary, and are not necessarily easy to see in their native habitat, pandas use scent marking as a means of communication. Instead of sending e-mails or posting fliers, pandas will “post” their personal information on a nearby stump, rock, or tree. This is done by lifting their stubby, white tails and rubbing their scent gland on the chosen item to broadcast vital information. A male panda, such as the San Diego Zoo’s very own Gao Gao, may even do a handstand to urinate or rub his scent gland high on a tree to advertise his size and virility. This message communicates to other passing males and females that he is strong, mature, and healthy. Other males may think twice about crossing paths with this formidable opponent, and it may help females become acquainted with the smell of Mr. Big, Strong, and Healthy. This could bolster the male’s chances of breeding with females in the future.
Communication works best when it’s a two-way street, so female pandas also do their fair share of scent-marking. A female panda’s personal scent changes during her estrus cycle, and male pandas can identify the changes in her scent, some of which are related to the changes in her hormone levels. Let’s picture a male panda roaming through the shadowy forest, looking for a female. His best chance is to sniff her out because the female will have spent some time using the scent gland under her tail to broadcast her olfactory message. Once the male actually locates his potential mate, he may keep tabs on her and check in periodically to see if she’s close to estrus. When he thinks the timing is right, he will approach, although he may not be the only potential suitor vying for the female’s attention. Males may compete to be her mate, but even the winner may not be chosen to couple with the female. It seems that sometimes the ladies have a preference about which male becomes the father to their cubs. Perhaps in the panda species the nice guy actually wins?
Although it does not seem related to reproduction, female pandas have been observed rolling and rubbing novel scents such as flowers and bark chips on their backs, much like applying perfume. The San Diego Zoo’s female, Bai Yun, particularly enjoys rolling in cinnamon and nutmeg. She then proceeds to spend her day cruising around smelling like a giant black-and-white pumpkin pie. There is yet no known reason why pandas do this, but it makes one wonder if pandas sometimes fragrance themselves just because they enjoy the aroma.
It is interesting to note how much information can be passed between pandas without a spoken word. Detailed information is communicated using only local, renewable, natural resources. In essence, pandas have found an extremely efficient means of communication without creating a carbon footprint. Could humans create a method of communication that is so effective, yet Earth-friendly?
This post highlights a few examples of what makes pandas such an amazing species and offers an example of biomimicry. The field of biomimicry involves learning about nature, learning from nature, and being inspired by nature. If you would like to learn more about the Zoo’s efforts in biomimicry, please visit our recently renovated Biomimicry section.
Sunni Robertson is a lead educator at the San Diego Zoo.