system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do we yell or make noise when we’re injured?

For example when you stub your toe or get a paper cut you often make a sound like ‘ouch’ or ‘tssssss’. Or if you are stabbed you would shout loudly. Is this ingrained in us or is it something we’ve developed over time?
gpt
Evolution.

Mammals from groups who yelled louder when hurt would warn their friends about a potential attacker who could help or run, both better than standing around doing nothing. The yelling also triggers a fear response so we are programed to be alert of potential threats.