Question

In five sentences or less, explain why the date of divergence between human pubic lice and gorilla hair lice might be a good estimate of the date at which humans living at the equator came under selective pressure favoring darkly pigmented skin. Make sure to indicate a) what this divergence date is thought to indicate and b) why this would lead to this type of selective pressure.

Genetic

Answer 1

Ans: The divergence date thought to indicate that license shared a common ancestor before million years ago, a divergence that is contemporaneous with their host.

The genes that are evolving faster in the lice are also the ones that are evolving faster in the primates, and those involve changes that actually affect the protein – changes that could make a difference in how the protein functions. That correlation, strongly suggests there was selective pressure applied to both host and parasite at those gene locations. This selective pressure due to changing environment, temperature etc.