posted by Alex .
Can anyone explain why natural selection works on phenotypes? And how that affects genotypes?
phenotype is the natural life form of the genotype. Nature operates on the life form in function, so natural selection has to do with the phenotype. As differing phenotypes show reproductive advantages, then those associated genotypes are reproduced.
Thank you! But I don't understand how the phenotype would affect the genotype. Isn't it supposed to be the other way around?
genotype makes phenotype. Several genotypes could make the same phenotype (long nose, for instance....could have many genotypes to make long nose on different folks, caucasians, chinese, etc all can have long nose phenotype, but all have differeing genotypes). So assisting one phenotype may enhance several genotypes.
Curly hair (C ) is dominant over straight hair (c).If two heterozygous curly haired people had children. What would be the phenotype ratio?