If too much exposure to the sun causes cancer, how are there still any fair-skinned people on earth? For the vast majority of human history, we didn’t have sunblock. Shouldn’t we gingers be extinct by now?

Question

If too much exposure to the sun causes cancer, how are there still any fair-skinned people on earth? For the vast majority of human history, we didn’t have sunblock. Shouldn’t we gingers be extinct by now?

In: Biology

Answer 1

Cancer usually occurs in older people, and people would have had children at much younger ages historically. It is highly unlikely that a person would develop fatal skin cancer from sun exposure before they already had kids. So it wouldn’t prevent them from procreating and passing their genes along. I would guess that historically most people didn’t live long enough to get cancer any ways, they would probably die from other diseases much sooner.