how do they know some animals are color blind?

Answer 1

Color vision is caused by certain chemical pigments in the retina of the eye, known as opsins.

In humans, there are three different opsins that are sensitive to different colors: red, green, and blue. The brain interprets levels of response from each type to create color perception.

Color vision based on three pigments is called "trichromatic vision." However, most mammals (and humans with red-green colorblindness) have only two pigments, and the result is "dichromatic vision."

This does not result in a complete absense of color vision. For example, most "colorblind" people tend to see the world in what a normal-visioned person would call shades of yellow and blue. (See illustration: http://img512.imageshack.us/my.php?image=cbsamplevs7.gif )

By analyzing the opsins present in the retina of an animal, we can determine how sensitive they are to color. It turns out that most mammals only have two. Most old-world monkeys and the great apes (including man) have three. Many marsupials probably also have three. Whales and dolphins, however, only have one, and are thus truly colorblind: everything appears to them as either shades of a single color, or as an absence of color.

Answer 2

Colorblind Animals

Answer 3

Scientists and researchers had done investigations and experiments to determine that. Scientists do examination of the cones inside the eyes and estimate what colors an animal could see.

For example: to determine the color vision of fish they use the technique called “MICROSPECTROPHOTOMETRY” in analyzing the VISUAL PIGMENTS and PHOTO-SENSITIVITY of cells to determine how and what colors a fish sees.

Scientists and researchers also do test for color vision with BEHAVIORAL TESTS.
For example: wiring up animals brains with ELECTRODES and observe how they respond to light of different color wavelengths.

They also test animal color sensitivity by trying to link color with different objects. A simple example of that is an experiment on a mouse using a soy milk dispenser with different colors. Only one dispenser will drop the soy milk so that will determine the mouse color sensitivity.

Answer 4

our and eye of any body has cone and roads like owl don't have con's that's why he is not able to see in day time and cock don't have roads that why they are not able to see in night time and in cone there are different cone for different colour after dissection of eye they came to know that animals are coulor blind

Answer 5

dissection of rods and cones. I would assume.

Answer 6

They asked them, of course. ;)