I’m referring to the human race evolving in the African continent and then migrating to the rest of the world.
Evolving in Europe made people light skinned to account for the reduction in sunlight exposure, are there any other traits which other ethnicities developed to adapt to their new environment? Or are the diifferent traits in different ethnicities just stuff that developed by chance and got somehow reinforced because of the isolation between populations?
This question came to my mind first thinking about “Asian eyes”, do they serve any “purpose”?
There’s also sickle cell anemia: IIRC it protects against something like the tse-tse fly or mosquito borne illnesses native to parts of the African continent
I believe that it offers a degree of protection against malaria. Or, enough protection that you live long enough to reproduce before dying a terrible, agonizing death.
I think it’s protective when you have one copy of the gene, and detrimental when you have two copies. Unfortunately, malaria was a strong enough pressure that the sickle cell gene was selected for, up to a certain percentage of the gene pool.
I thought that there was supposedly something about the altered shape of the cells themselves that offered a degree of protection from malaria? IDK, I don’t live in an area where malaria is endemic, so it’s mostly not a concern, just something we covered in biology and genetics in high school.
Yeah, I think you’re right (on both counts unfortunately, but that’s evolution for you).