Social play behaviour in the domestic cat

This detailed developmental study described how kittens in litters engage in social play, cataloguing motor patterns such as the belly-up, stand-up, pounce, and chase, and charting how their frequency changes with age. Social play peaks in the weeks after the eyes open and gradually gives way to more object- and predatory-oriented play as kittens mature, with the transition shaped by weaning and rising aggression among littermates. The careful ethogram became a standard framework for interpreting feline play, distinguishing it from true aggression, and it remains foundational reading for anyone studying the ontogeny of behaviour in cats.