Biologists from California have advanced their version of the explanation of the contrasting black and white coloration of large pandas: white color helps them remain invisible against the background of snow, and blacks hide in the shade. In addition, black ears and blackness around the eyes are used by pandas to communicate with each other.
First, to test all options, the researchers divided the body of the panda into areas of different colors and compared them to the corresponding parts of the body in other predatory animals. For the analysis, 195 species of carnivorous animals were selected, including 39 representatives of the bear family. Then each section of all species of animals was related to various aspects of the environment: in what conditions does this species live – in snowy terrain or shaded, the climate of habitat, when awake and asleep, leads a social life or a single life. After that, the scientists made a correlation between the coloring of each selected area of the body and the environmental aspects.
As a result, a high degree of correlation was found between habitat in shaded forests and dark coloring of the limbs and upper back and between living in snow-covered terrain and white coloring of animals. The contrast in the coloring of pandas, therefore, will be explained by their bamboo diet. Because of the low-calorie diet, pandas can not stock up a lot of fat, so they do not hibernate in winter, like many other bears, but change their habitat depending on the season. In snow-capped mountains, white color helps them to merge with snow, and black stripes allow to get lost in the shade of tropical trees. That is, evolution awarded them a contrasting color, which is won simultaneously in the shade of the forest, and against the background of snow.
However, this assumption still does not explain what adaptive value the white parts of the body have outside the snow-covered habitats (for example, in the forest), and whether pandas prevent the black limbs from remaining unnoticed in the snow, reports Behavioral Ecology.
Also, American biologists have revealed a correlation between the presence of dark color of the ears and “glasses” around the eyes and the sociality of animals. Black “glasses” around the eyes, most likely, are used for individual recognition of relatives, or for demonstrating aggressive intentions. The last version looks plausible: the pandas, in order to demonstrate to other individuals peaceful intentions, often hide the muzzle and cover the dark marks around the eyes with paws.