People have long wondered why zebras have stripes. There are many hypotheses. But only recently, studies have shown that the stripes serve as a warning coloration. We talk about the discoveries of scientists.
Where do zebra stripes come from?
First, let’s clear this up once and for all: zebras are actually black with white stripes. At first glance, it may seem that the opposite is true – after all, the black stripes on many zebras end on the stomach and closer to the inside of the legs, exposing the rest of the body as white. But looks are deceiving.
All zebra fur, both black and white, grows from follicles containing melanocyte cells. All animals have them and are responsible for the production of the pigment that gives color to the skin and hair. In both cases, melanocyte cells produce melanin, a pigment that is visible from the outside. In zebras, chemical messengers determine which melanocytes deliver pigment to which area of the fur, thus creating a black and white pattern. What is important is that their white fur is indicative of the absence of melanin. Black is considered the “default” zebra color.
Under all that fur, zebras also have black skin. A shaved animal without any stripes is not so easy to spot among other black ungulates.
Why do zebras have stripes?
In recent years, one particular idea has been gaining momentum, which basically says that zebra stripes serve as a deterrent, but not for predators – for insects, and specifically horseflies. Researchers from the University of Bristol have figured out why zebra fur has thin stripes and distinct contours.
The team of researchers suggests that the thin dorsal stripes serve to minimize the size of the zebra’s localized features that are attractive to biting flies. Horseflies have been around since dinosaur times, and their bites are quite nasty. Of course, horses and zebras have thicker skin than humans, but even for them horseflies are problematic. It is difficult for animals to get rid of flies because they do not have hands or insecticides.
Scientists have found that horseflies are attracted to large dark objects, but to a lesser extent dark broken patterns. All-gray designs were associated with the most insect landings, followed by patterns with large black triangles at different angles, and then small checkerboard patterns. In another experiment, it was found that contrasting stripes attracted fewer flies, while more uniform stripes beckoned more. Since the researchers simply couldn’t take the zebras and swap their stripes, they wrapped the horses in different sheets.