Thesis (B.A., Honors in Sociology)--Harvard University, 2005. / Includes bibliographical references (leaves 82-83).

Thesis (B.A.)--Harvard University, 2005. / Includes bibliographical references (leaves 82-83). Also available online (PDF file) by a subscription to the set or by purchasing the individual file.

Playing is a common behavior among juveniles of many mammalian species, including rats (Rattus norvegicus). The mechanisms underlying the change that occurs in the play fighting of male rats at puberty were the focus of this thesis. It was found that castration at weaning disrupted the formation of male-typical dominance relationships, but did not alter the pubertal changes in play fighting, whereas neonatal castration prevented the shift from juvenile- to adult-typical behaviour at puberty. This transistion is male specific and cannot be induced in females by exposing htme to more extreme social contexts, involving interactions with unfamiliar males. The change in play by males at puberty is not, then, a byproduct of other sex differences, but results from a highly specific mechanism in early infancy. The significance of this sex difference is explored with respect to the functions of play fighting in rats and other species. / xii, 137 leaves : ill. ; 28 cm.

Play fighting in kindling-prone (FAST) and kindling-resistant (SLOW) rats: Potential genetic controls over the components of play. Even though the behavioral components of play fighting have been well characterized in the rat, little is known about the underlying neurobehavioral mechanisms that control them. FAST and SLOW lines of selectively-bred rats were used to determine whether the components of play fighting were dissociable. Differences in their respective play profiles suggest tht there are genetic differences in the expression of differnt components of play. The effects of gene-environment interactions on the components of play suggest that playful attack and playful defense may be differentially labile, and that socially-relevant envionmental manipulations may have a greater impact on social interactions in adulthood than in the juvenile phase. Furthermore, these findings suggest that the genetic constraints on each of the components of play fighting give each component a unique pattern of context-dependent change. Future experiments using FAST and SLOW, as well as other selectively-bred lines of rats may provide insight into the proximate mechanisms regulating play fighting. / viii, 125 leaves ; 28 cm.

Thesis (Ph. D.)--Psychology, Georgia Institute of Technology, 2006. / Terry Maple, Committee Chair ; M. Jackson Marr, Committee Member ; Rebecca Snyder, Committee Member ; Marc Weissburg, Committee Member ; Paul Corballis, Committee Member ; Roger Bakeman, Committee Member.

The prevalence of play in the animal kingdom makes it a well-studied phenomenon, yet little is known about play fighting behavior in bears. I investigated the effects of sex, partner (dam or cub), and early rearing conditions on play fighting behavior in giant panda cubs by observing video tapes that were recorded at two facilities in China over a three-year period. Two of the three factors, sex and partner, had significant effects on the play fighting behavior of giant panda cubs. I found sex differences in play fighting, with males exhibiting significantly higher rates of biting behavior than females during play bouts with other cubs. This lends support to the motor training hypothesis and suggests that there is a relationship between adult roles and earlier play fighting behavior. Partner had a significant effect on play fighting, in that cubs exhibited significantly higher rates of Bite, Break Away, Paw Swat, and Re-engage behaviors during play bouts with cubs. These differences suggest that cubs and dams might provide different opportunities as partners during play fighting bouts. Because some behaviors occurred at higher rates with dams, it is possible that dams engage in self-handicapping behavior during play fighting bouts with cubs. Early rearing conditions did not have significant effects on behaviors when they were examined by category or by individual behaviors. Similar results were found when cubs that had access to adult females after six months of age were excluded from the analyses. These results suggest that early rearing conditions have little effect on the play fighting behavior of captive giant panda cubs. Certain aspects of giant panda behavioral ecology, however, might contribute to stability in play signals, regardless of early rearing conditions. Future studies of play fighting behavior in bears should further examine these and other factors, and that data from these studies need to be interpreted in light of the relationship of bears to other carnivores.