社会性动物也称为群居动物，例如人类、狗、猴子、大猩猩、蜜蜂、狮子、蚂蚁。它们群族中，可能由一个到多个家庭组成。每个家庭成员各自有比较明显的地位。

家猫虽然是独立的猎人，但也算社会性动物，家庭饲养的猫与流浪猫都可以与同伴关系不错，包括共同抚育幼猫、母猫带小猫给其他只猫认识、送食物给哺乳中的猫妈妈、公猫也多少会照顾小猫、幼猫易有优先进食权等等；家猫最特别之处，是生理及心理可以适应独居生活，也可在食物充足情况下适应群居生活。

为保障其种族势力范围，社会化动物的群族中通常有首领。在繁殖期中，常有新一代挑战旧首领，并发生激烈打斗。为保障觅食优势，社会化动物的群族会霸占一个地方/地盘。

Social animals are those animals which interact highly with other animals, usually of their own species (conspecifics), to the point of having a recognizable and distinct society. Many animals are social to the extent that mothers and offspring bond, and males and females interact to mate, but the term "social animal" is usually only applied when there is a level of social organization that goes beyond this, with permanent groups of adults living together, and relationships between individuals that endure from one encounter to another. In the case of social animals, not having those social interactions can be detrimental to the animal's development; they are crucial. These interactions and socializing help to develop emotional stability and flexibility for the span of the animal's life.