Re: What animals can see in color? How is it determined ?

Many animals have the ability to see colors. This ability is based on the types of visual pigments in a cell.

There are animals known with 2, 3, or 4 different pigments or visual cell types. Humans have 3 different pigments and can differentiate about 200 colors. Most of this analysis is done by the brain, not the eye. Therefore, it is difficult to tell how many colors an animal can differentiate based on the number of their eye pigments alone.

Many fish can see colors (e.g. Phoxinus, Crenilabrus). Some amphibians can see colors (frog: Rana temporaria, toads: Bufo bufo, some salamanders) and they usually have two pigments. Most reptiles can see colors (snakes, turtles). Birds: general rule: birds that are active during the day can see colors, but birds that are acitve during the night cannot. Mammals are generally bad in color vision. Examples of color-blind mammals are rats, hamsters, rabbits, and dogs. Cats are weak, but can see some colors. Mammals that are quite good are guinea pigs, sheep, zebra, horses.

Also some invertebrates are able to see colors. Some Cephalopods (e.g. sepia, but not octopus). Crabs are generally good in color vision. Many insects (all beetles, hymenopterans (bees, wasps, ants), homopterans (ture bugs), and all flies. All insects are unable to see red light (only known exception are ants), but some are able to see UV (ultraviolet) instead.

The color vision was determined by training an animal to respond to a color or by measuring the electrical response of single visual cells or the whole eye.

Best wishes
Dr. J. Ziesmann