Scientists have been arguing for decades.evolutionary causes of black and white stripes on the body of zebras. At the moment they have three theories about the purpose of the unusual texture of animals - they may be needed to protect against insects and predators, easy recognition of relatives and for proper heat exchange in hot African conditions. The latter theory seems the most plausible, and recently the heat transfer properties of the strips have been proven by two amateur naturalists.
The study was conducted by spouses Stephen andElisson Cobb - they have spent years in Africa and have done various environmental studies. During the collection of field data on a number of animals in Kenya, they conducted the first ever study to identify the heat exchange functions of the stripes of zebras, while in their natural habitat. Previous studies were usually conducted in special pens.
Black and white stripes of zebra needed for heat transfer
While tracking two zebras, a stallion anda mare, the researchers noticed a difference in the temperature of black and white stripes - the same thing previously observed by other scientists. According to biologists, temperature differences help maintain the body temperature of the animal at an optimal level, creating convective air movement. However, the Cobb couple made a new discovery.
By measuring the body temperature of a dead zebra theyfound that if there is the same strip cover, it has a higher temperature - this is a clear sign that other processes are involved in thermoregulation. According to researchers, thermoregulation works only with live zebras, because they have an amazing skill to lift hair on black stripes, leaving white stripes even. They are sure that this is what helps them to take away the excess heat from themselves.
Alison Cobb in Nairobi, 1991
Also in thermoregulation, the sweat removal method plays a big role - all the moisture from the skin is transferred to the ends of the hair in the form of foam drops, which evaporate much faster than ordinary drops of moisture.
The mechanism of regulation of heat in the body of a zebra -much more complicated and interesting process than we could ever imagine. To fully understand how the bands help the zebras to control the temperature, we still have a lot of work to do to collect evidence, ”shared Alison Cobb.
Why zebra black and white stripes? Other theories
With all this, do not forget about otherspossible destinations of black and white stripes on the body of zebras, because they can have several functions at once. For example, they are absolutely sure to scare away flies and other insects from animals - this was proved during the experiment, where the usual horse was dressed in a striped suit.
Also strips can be used ascamouflage that protects animals from predators. This is evidenced by studies whose results were published in the scientific journal PLoS ONE in 2011 and 2013. Read about all the assumptions of scientists can be in our material.
Which of the three theories seems to be the most realistic? You can share your opinion in the comments, or in our Telegram-chat.