SSS 2012-02-09

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How did the zebra get stripes. One theory holds that stripes help confused predators¹. But stripes might be primarilly to protect zebras from ferocious² insects. That's according to the study in the Journal of Experimental Biology. Horseflys are abundant in Africa, they deliver a painful bite that's spread diseases and destruct animals from grazing, the flies use polarized light hiding water as a guide to place to mate and lay leggs. And they readlike such light hiding dark in mamal hairs as sign of blood meal. Zebra embryos³ start out dark and developed their white stripes before birth. Could the stripes confuse flies?

 

The researchers just went to a farm infested⁴ with horse flies ,where they set up models a black and white stripes of varying angels and widths. That's changing the direction of their reflected polarized eyes light. They tracked at the patterns that the flies are interested. They then tested the models of horse's colour, black, brown, white or zebra's striped. and again tracted the effect on flies. Turns out that black and white stripes on zebra are optimal⁵ for avoiding of horseflies attention.Meaning that zebra may evolve  stripes to ward⁶ off the disease-carrying insects and to dine in peace. 

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