It was an experiment to make a perfect mouse society. 4 hand picked super healthy mice to populate a world with all their needs met. plenty of food/water space. Colony quickly grows to 600 or so, then it starts breaking down. Females become aggressive. Homosexuality becomes rampant. Females stop caring for and even attacking/killing their children. males and females stop mating. Little groups form that roam around attacking other groups for no reason. Much of the colony stays empty and they all huddle in one place. With no mating going on, within 2 years all the mouse are dead. Only ever reached a little over 600 when it was made to house over 3000.