Wonder why do some cats have two different colored eyes? The key to eye color is melanin. Melanin is a black or dark brown pigment which is present in hair, skin, and eyes of animals. According to Scientific American:
Brown eyes are rich in melanin deposits, and blue eyes indicate a lack of melanin.
When eyes are blue it is the scattering of light in the iris that causes it rather than pigmentation — it works just the same way that the sky looks blue.
All kittens are born with blue eyes and when they get older the melanin changes their eyes to copper, orange, yellow or green. Sometimes this happens in one eye and not the other. This happens particularly in white cat — the fur of white cats has no pigmentation, the cause being one specific gene.
Why Do Some Cats Have Two Different Colored Eyes? It’s in the genes–
It is rare for a non-white cat to have odd eyes, though this does arise. Normally the odd eyes are caused by the white gene interfering with the way the eye absorbs melanin. It is often believed all odd eyed cats are deaf. In fact many, though not all, white cats with blue eyes are deaf, and around 30% of odd-eyed cats suffer this problem. In the latter case deafness occurs on the side of the blue eye. White cats with orange eyes are no more likely to be deaf than any other cat though.
Why Do Some Cats Have Two Different Colored Eyes? Maybe god just made them that way because they are so cute
Odd-eyed cats have often been prized as special cats, especially in the east. According to Swimming Cats:
Mustafa Kemal Ataturk (1881-1938), who founded the modern Republic of Turkey in 1923, declared that his successor would be bitten on the ankle by an odd-eyed white cat. And secondly, legend has it that Mohammed (570 – 632), founder of the Islamic faith, possessed a Traditional Turkish Angora he regarded so highly that rather than disturb it as it slept on his robe, he cut off the sleeve. Mohammed’s Traditional Turkish Angora was reputed to have been odd-eyed (one blue eye and one gold eye).
It is not only cat’s of Turkish origin that have two different colored eyes. In particular, the Japanese Bobtail often exhibits odd-eyes in both all-white and calico colorings. These cats are also highly prized. One strange effect of the odd eyes is that the blue eye creates a red-eye with a flash photograph and the other eye does not. The result can be interesting.
In summary a cat has odd eyes because of the effect of melanin in one eye and not the other. This is frequently related to the gene involved in the creation of white coats.