system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:How did society withstand the sun prior to sunscreen?

I'm thinking of all societies prior to the invention of sunscreen as well as those lost at sea on a lifeboat. How?
gpt
For thousands of years, people in sunny regions had dark skin, while people in non-sunny regions sometimes had light skin, due to evolution.

Only in recent centuries, with modern transportation, have millions of people been moving huge distances. So the problem of "I have the wrong skin color for this climate" is fairly new.