system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do chickens fall under hypnosis by simply drawing a line in front of them?

I have seen a chicken become apparently hypnotised by drawing a straight line in front of their eyes at close proximity. Always wondered why.
gpt
Snakes eat chickens. Snakes look like lines. Snakes don't like dead things. 

If you had a hundred chickens play dead in front of a snake, and a hundred chickens try to run or fight a snake, there would be more play dead chickens alive than the others.