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Scientists have learned, as a symbol of the connoisseurs — owl owl — rotating head

photo: morguefile.com

As it became known «MK», scientists in the past have noticed the unique ability of owls to rotate the head «around its axis». However, so far no one has described how they do it. Biologists Catherine Gritsyshin, Alexander Kuznetsov and Alexander Panutina examined the carcass tawny owl (who died with his death the owl was taken from scientific biological collections of the Institute of ecology and evolution named after. A. N. Severtsov). In the study, the object is turned counter-clockwise to the maximum possible angle – he was equal to 360º, frozen in a normal freezer and in this position did a CT scan. After the examination, the carcass was thawed, prepared and made sure that the joints, muscles and ligaments of the neck remained intact. From this it followed that the structure of owl is designed for such a huge turn of the head.

Thanks to computer scanning in the hands of scientists turned out to be a three-dimensional skeleton model of a tawny owl, which they calculated the angles of rotation in all 13 joints of the neck. It became clear that the owl can turn his head at an angle up to 360º only in the case when the head tucked against her shoulder. In this position, the cervical vertebrae of birds can not only rotate right and left, but also to drift forward, backward and to the sides, like the links of the cardan drive. The neck vertebrae owls can be compared with a children’s toy the «Rubik’s snake».

According to biologists, nature has endowed owls with this unique ability for a reason. Such mobility is not available from one group of birds. Owls — nocturnal raptors, are very large and so deep-set eyes. For this reason, they are inactive and can’t be rotated, as, for example, people who want to see sideways. In addition to this, owls, like humans, the eyes are focused forward for the bulk of the so-called binocular vision. To see her back, owls, unlike other birds whose eyes are located at the sides of the head, have to turn my head entirely. And since owls often hunt «with prisady» (sit on a branch waiting for a long time and his victim) to keep potential prey in sight they need to have the opportunity to «lead» the victim’s eyes, for a moment not letting her out of my sight. So we have to twist the head.

Perhaps Russian scientists measured the mobility of the neck of the owl is more than what the bird actually uses in your life. But there is another option. Owls use the full rotation of the head, but to the observer it is hard to notice: under plumage he looks like the owl did not turn his head. Now the researchers plan to figure out how many degrees the owl turns his head in vivo.