Understanding mouse behavior is vital for researchers using murine models for scientific analysis. Mice are nocturnal animals, usually preferring to sleep during the day and eat and perform activity at night. Mice are a social species and thus are typically caged in groups or 4 - 5 mice. Male mice behave territorially and thus will not tolerate other males in their cages so male laboratory mice should not be mixed post-weaning. Females tend to be less aggressive than males.