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Name: Mostafa
Status: other
Grade: other
Location: Outside U.S.
Country: Egypt
Date: Winter 2012-2913

What is the scientific basis of changing gender in birds? Is there any hypothesis to be constructed for studying this phenomena? We have recorded some observations of pheasants changing plumage color of females to males.

Hi Mostafa,

Thanks for the question. Ultimately, the scientific basis for changing of gender in birds would be a change in gene expression. However, I cannot think of an example of sex changing occur in "real-life." If you know of one, please let me know.

I would be hesitant to assume that a change in plumage color is indicative of a change in sex (or gender). There may be environmental factors (such as temperature or food supply) that would trigger a change in plum color. For instance, mating is inhibited if there is a lack of food supplies. If mating is inhibited, one would expect that the other aspects of courtship (such as plumage color) would also be altered.

I hope this helps. Please let me know if you have any further questions.

Thanks Jeff


From this web site:

Due to an ovarian change that affects the balance of hormones in chickens and other birds, it is very rarely possible for a female bird to adopt male secondary sex characteristics (feathers, combs, and even crowing in a hen turned rooster). However, this is not a true sex change because the bird cannot fertilize eggs. On large farms of 10,000 or more hens, this has been definitively observed. There are some animals that actually change sexes, but the chicken isn't one of them.

Sincere regards, Mike Stewart

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