>>14071268It's called "behavariol sink" essentially some guy named John Callhoun got a bunch of rats and gave them all the food and water they'll ever need. It started out normally, rat population exploded.
But then something strange happened. At a certain point the rats stopped breeding, near the end of the experiment the rats were cannibalizing eachother and killing their kids. The rat population then collapsed, if you want more information there's a bunch of videos about it.