6Object play occurs in diverse animals in addition to birds and mammals. Although many carnivores engage in object play in a predatory context, many non-predators do so also. Conjectures over the years on the motivation to play are reviewed dealing with intrinsic, developmental, and stimulus factors. We then report on quantitative studies of the play of puppies from 6 litters (3 breeds) when given 5 different toys with different sensory and functional properties at half week intervals from 3 to 7 weeks of age. The propensity to engage with objects begins early, play complexity increases rapidly, the structure of the play is similar to adult object play, and breed differences were found. Object play with predatory characteristics appears before weaning, suggesting that hunger is not the primary motivation. Studying the development of object play in different dog breeds may be useful in addressing questions of domestication and play evolution.
