system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why Has Evolution Not Taken Care of the Need for Glasses and How Did our Early Ancestors Survive?

Before the invention of convex and concave prescription glasses, how did early humans 'see'?
gpt
Evolution is not survival of the perfect but survival of those who survive. Humans developed tool making skills. A nearsighted person who could produce a good spear point was as valuable as an eagle eyed person without a weapon.

Natural selection does not actually cull all deficient genes. There is so much genetic material some perfectly useless stuff gets passed on.

Until writing and sewing came along the need for perfect vision was not that great.