Saturday, August 16, 2014

Albinism in Animals

Science class taught us that the traits of the parents get passed down to their offspring.  For example, two people who have genes for brown eyes will mostly likely have brown-eyed children.
A Leucistic American Goldfinch (photo: Gay Schroer)
But what happens when two perfectly normal parents produce an albino offspring?  Albinism is caused by a genetic mutation that prevents the development of melanin, the pigment that colors our eyes, skin, and hair.  That lack of pigment causes albino animals to appear entirely, or at least mostly, white, and have pale blue or pink eyes.  Some animals are naturally white, like Mute Swans for example, but only albinos will have the pale eyes.  Animals that depart from their normal coloration and have some white on their body, but not completely white, are leucistic.

In the wild, being albino can cause a variety of problems. The white coloration causes the animal to stand out, making it easier for potential predators to spot. However, the white coloration might also make the animal unrecognizable as a prey species.

Another issue caused by albinism is that members of the albino’s own species may reject it. Albino animals, especially birds, may not be able to find a mate because they lack the coloration and patterns necessary to catch the eye of the opposite sex.
A wild Albino Barred Owl (Photo: Kelly Bietsch)
Albinism also affects eyesight. Melanin helps in the development of the eye, and animals that lack melanin often have poor vision. An albino’s eyes are often more sensitive to light, less able to distinguish color, and less able to perceive depth. It is possible that an albino animal would have more trouble finding food or seeing danger, thus decreasing its chances of survival.

In the wild, albinism is not common. The frequency of albinism occurring varies from species to species, but generally albinism is more common in birds than in mammals. According to the Missouri Department of Conservation, albinism occurs in approximately one out of every 10,000 mammal births, while approximately one out of every 1,764 birds is albino. Although most, if not all, species can produce albinos, the only commonly albino species are those that are domesticated. Many people like to have albino pets, whether it be a cat, snake, or rat.
Kahn, WBS's albino Burmese Python (photo: JoHanna Burton)
At the World Bird Sanctuary, we do have a couple of albino animals. One of the most popular animals (depending on how you feel about snakes) is Kahn, our albino Burmese python. A normally pigmented Burmese python is patterned tan and dark brown, with dark eyes. Kahn is patterned white and pale yellow, and if that weren’t enough to convince you that he is albino, you could take a look at his pink eyes.
Kahn enjoying his pool on a hot summer day (photo: JoHanna Burton)
You can come to visit Kahn at World Bird Sanctuary's Nature Center, and on warm summer days you might just find him outside with a naturalist, enjoying a refreshing bath.

Submitted by JoHanna Burton, World Bird Sanctuary Naturalist

No comments: