A photo from open sources
Reindeers are closely associated in western countries with Merry Christmas and Happy New Year. It is believed that it is the reindeer pulled by a sleigh of Santa Claus delivering gifts to children. However not everyone knows one curious fact: closer to winter Holidays in these artiodactyls sharply and noticeably change color eye. Despite the fact that it looks like a real Christmas “bike”, we are talking about a long scientifically proven phenomenon.
Annually, towards the end of December, the color of reindeer eyes changes from brown to beautiful dark blue. Norwegian biologists studied this phenomenon and recently established its causes. According to scientists, metamorphoses that occur with the eyes of these animals, caused by the unique light conditions beyond the Arctic Circle. It turned out that the reindeer eyeballs are adapting to radically opposed types of lighting characteristic of Arctic.
Catholic Christmas, as you know, falls in the middle A 10-week period of constant twilight in the Arctic. Thanks the lack of sun in the arctic landscape is dominated by bluish shades and blurry shapes. But since mid-May, the local lighting becomes incredibly intense because the sun is not sits completely, and its rays blind all life, reflecting off not had time to melt the snow. The contrast is striking.
A photo from open sources
So that horned Arctic inhabitants can see better in each of these seasons, nature has allowed deer to change eye color with brown to blue. Brown eyes function well in bright blinding lighting. The blue ones, although they see less clearly, a thousand times more sensitive to light, because artiodactyls can beautiful to see in the darkness when the sun leaves for a long time Arctic.
Scientists have been figuring out how this happens for 10 years. As a result, the Norwegians determined that the deer does not change the color of the iris, but reflective surface behind the central area of the retina. This part the eye, called a “mirror”, is absent in humans, however found in many nocturnal animals. “Mirror” reflects the slightest light inside the eye, allowing nocturnal animals to see even in negligible light. For example, a cat’s eyes “glow” in due to this effect, due to which it perfectly sees at night.
The sun
