It is known that many differences between related species are due to genetic drift rather than selection. Is it known that differences between males and females within a species are due to genetic drift?
There is as much genetic drift on the X and Y chromosomes as on any of the other chromosomes, so at least some of the differences between sexes must be caused by it.
The Y chromosome is physically much smaller than all the other chromosomes. In particular, it’s not an equal partner to the X chromosome. From Wikipedia, I learned that the human Y chromosome contains 86 genes, which code for only 23 distinct proteins.
One example of a sex-linked trait that’s wasn’t due to selection is colorblindness, which is common only in males because the relevant genes are recessive and located on the X chromosome.
At some point, a population of organisms developed some sex determination genes. Over time, this system developed into the XY sex determination system: sexual dimorphism due to the segregation of sex-determining genetic information onto a single highly degenerate chromosome. I think it’s very implausible that this segregation is without evolutionary benefit. The occurence of sex-linked monogenic traits like the example you give here are a side effect whose evolutionary cost was outweighed by the benefit of the development of the XY system. So I don’t think this is a good example for the claim you are trying to defend.
It is known that many differences between related species are due to genetic drift rather than selection. Is it known that differences between males and females within a species are due to genetic drift?
There is as much genetic drift on the X and Y chromosomes as on any of the other chromosomes, so at least some of the differences between sexes must be caused by it.
The Y chromosome is physically much smaller than all the other chromosomes. In particular, it’s not an equal partner to the X chromosome. From Wikipedia, I learned that the human Y chromosome contains 86 genes, which code for only 23 distinct proteins.
One example of a sex-linked trait that’s wasn’t due to selection is colorblindness, which is common only in males because the relevant genes are recessive and located on the X chromosome.
At some point, a population of organisms developed some sex determination genes. Over time, this system developed into the XY sex determination system: sexual dimorphism due to the segregation of sex-determining genetic information onto a single highly degenerate chromosome. I think it’s very implausible that this segregation is without evolutionary benefit. The occurence of sex-linked monogenic traits like the example you give here are a side effect whose evolutionary cost was outweighed by the benefit of the development of the XY system. So I don’t think this is a good example for the claim you are trying to defend.