Black and white stripes look beautiful on a zebra, but why do they need them? A new study has shown that such a funny color helps animals fight biting flies that can tolerate dangerous diseases. This statement contradicts the opinion that the stripes serve as camouflage, which protects the zebra from large predators. Until recently, this theory was supported by various studies. It turns out that the extreme color is not enough that it does not protect, it also makes the zebras more visible to predators on the dusty African plains? Not certainly in that way. Let's figure it out.
Contrast stripes in the role of camouflage
Previously, scientists had suggested that during movement, the stripes create a flickering effect that confuses predatory animals that hunt zebras. Studies published in the journal PLoS ONE in 2011 and 2013 said that the stripes help to mask a moving object and prevent lions from estimating the speed of movement of a particular individual due to the fact that it becomes more difficult to distinguish the outlines of an animal, especially in the herd.
Similar contrasting camouflage was used on warships during the First World War. The color of the vessel, as in the photo below, created a distortion of its appearance.
Early studies have shown the efficiency of this strategy, but they were all carried out in the laboratory using computers and humans, not animals. Therefore, it cannot be argued that in animals the eyes react to black and white stripes in the same way as in humans.
Even if zebra stripes serve as a kind of camouflage, this does not mean that they are intended for this purpose. Another question arises: why did nature not award other animals with black and white stripes? Perhaps because they are meant for another.
Protection against flies
New research has shown that black and white stripes scare away flies. For the first time such an idea was put forward in a paper published in the Journal of Experimental Biology last year. Scientists have discovered that it is the zebra, and not the horse with white, gray or black color of wool, that attracts the least gadflies. Moreover, the narrower the strips, the smaller the flies.
Flies are attracted by the light reflected from the water. The researchers suggested that the black and white stripes of a zebra give the opposite effect, confusing them. Scientists investigated seven species of the horse family, with and without stripes.
A paper published in early April in the journal Nature Communications compared the geographical distribution of species and subspecies of these animals and biting flies, known as gadflies, which are carriers of dangerous diseases. Scientists have discovered that zebras with a black and white color prevail in the permanent habitats of these insects.
The figure below shows how the color and pattern of the animal's fur (dots from white to black inside the circle) coincide with the activity of biting flies in their habitat (dots from blue to red / orange, located outside the circle).
However, the study did not provide any evidence that contrasting camouflage scares predators.
The article is based on materials .
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