Striking features of color vision in animals
In the eyes of ordinary butterfly is five times more color-sensitive cells than the human eye. Why would she and other animals need so many?
The world of nature is buried in the shades - a dazzling plumage of parrots, endless fields of wild flowers, but people see only a small part of the whole palette.
We perceive color by special cells in our retina - photoreceptors, subdivided into rods and cones, which are responsible for the latest and color vision.
Most people have three types of cones - perceiving red, green or blue, which in combination provide the millions of colors. Some people can not distinguish all shades, that they lack to one of the types of cones -.. Usually red.
And others, on the contrary, there is a fourth type of cone. These tetrachromacy have additional cones, which are somewhere between red and green, allowing their owners to distinguish between shades where others see one and the same color.
We are accustomed to thinking of human vision more perfect than the animals, however, some representatives of the animal world is far ahead of man's ability to distinguish colors. Just look at these examples of the incredible range of color vision in animals!
Butterfly Graphium sarpedon has 15 types of photoreceptors
Butterflies species Graphium sarpedon one type of cones perceive ultraviolet, one purple, three - different shades of blue, a blue-green, four - and five green - red. Total out of 15, that five times more than that of men. Why it so much? Many other insects cost three.
Researchers believe that the butterfly in everyday life use only four types of their photoreceptors, while the other 11 are used for narrow tasks, for example, to distinguish between the rivals against the backdrop of lush greenery and blue sky. A similar system of detected in 6 photoreceptor butterfly, Papilio xuthus.
In the sea mantis shrimp types of color photoreceptor 12
These crustaceans stagger the imagination. Under the rainbow colored hiding formidable hunters, a shot so fast that generates an underwater shock wave and is able to break the glass aquarium.
Why do they need 12 types of cones? And does this mean that they perfectly distinguish colors?
A study in 2014 revealed that in fact their color vision is not so good. The spectrum of perception rather narrow cone, that is, one sees only a specific color. This means that the brain does not have to handle millions of incoming signals to determine the color and therefore recognition of different colored recovery is faster.
Some birds can see ultraviolet colors plus the usual
The whole color range, advanced UV light, allowing the birds to see one another feather in all its glory.
Where we see a sparkling palette of colored feathers, birds see more. Many of them not only to distinguish colors better than we do, but also have additional UV cones, and see what is hidden from us.
Bumblebees - trichromats
As with humans, the good old bees have three types of color photoreceptor. But, unlike us, their cones are shifted closer to the ultraviolet end of the spectrum. This allows them to see the mark on the flowering plants, directing them to the location of nectar, the lights along the runway.
boas and pythons can "see" in the infrared part of the spectrum
A detailed color vision snakes are not too developed, but some of them may feel the long-wave infrared range using a set of bodies that act as infrared goggles.
These "pit organs" are usually located on the head of a snake between the eyes and nostrils, and contain thousands of receptors that are sensitive to infrared light with a wavelength longer than that of the visible spectrum. People also feel the infrared light as heat.
Use the "eye spots" starfish see the light, but not the color of
And at the other end of the row are starfish and some worms that have "eyespots" - light-sensitive organs in the skin.
Starfish does not distinguish between colors and is not able to observe the fish swimming by, but can navigate among the coral reefs - large stationary objects.