Abstract: Hawk-dove games have been extensively used to predict the conditions under which group-living animals should defend their resources against potential usurpers. Typically, game-theoretic models on aggression consider that resource defense may entail energetic and injury costs. However, intruders may also take advantage of owners who are busy fighting to sneak access to unguarded resources, imposing thereby an additional cost on the use of the escalated hawk strategy. In this article we modify the two-strategy hawk-dove game into a three-strategy hawk-dove-sneaker game that incorporates a distraction-sneaking tactic, allowing us to explore its consequences on the expected level of aggression within groups. Our model predicts a lower proportion of hawks and hence lower frequencies of aggressive interactions within groups than do previous two-strategy hawk-dove games. The extent to which distraction sneakers decrease the frequency of aggression within groups, however, depends on whether they search only for opportunities to join resources uncovered by other group members or for both unchallenged resources and opportunities to usurp.

Abstract: In the wake of telling critiques of the foundations on which earlier conclusions were based, the last 15 years have witnessed a renaissance in the study of social learning in apes. As a result, we are able to review 31 experimental studies from this period in which social learning in chimpanzees, gorillas, and orangutans has been investigated. The principal question framed at the beginning of this era, Do apes ape? has been answered in the affirmative, at least in certain conditions. The more interesting question now is, thus, How do apes ape? Answering this question has engendered richer taxonomies of the range of social-learning processes at work and new methodologies to uncover them. Together, these studies suggest that apes ape by employing a portfolio of alternative social-learning processes in flexibly adaptive ways, in conjunction with nonsocial learning. We conclude by sketching the kind of decision tree that appears to underlie the deployment of these alternatives.

Abstract: The use of nonhuman primates, particularly rhesus macaques (Macaca mulatta), as the best model for human physiological and cognitive aging is broadly accepted. Studies employing nonhuman primates to investigate behavioral changes that may occur with increasing age, however, are not common mostly because of the unavailability of appropriate subjects. Recent longitudinal human studies suggest that individual personality might play a large role in aging “successfully” and in the retention of high levels of cognition into old age. As a result of the demographic trend of increasing numbers of aged monkeys and apes in captivity, an opportunity exists to further investigate behavioral aging using the monkey model.

Abstract: The work of innovation management involves cross-functional coordination among specialists and managers with different work orientations, time horizons, professional backgrounds, and values (Ford and Randolph, 1992). While strong connections across functions are critical for new product development success (Green et al., 2000), some managers may be more adept at fostering effective cross-functional relationships than others. In this article, the authors empirically examine the factors that distinguish reputationally effective innovation workers from their less effective peers. Drawing on the work of Tsui (1984, 1994), reputational effectiveness is defined as the degree to which a manager has been responsive to the needs and expectations of constituents. This research examines the relational skills and interaction patterns of more (versus less) reputationally effective managers. A large business unit of a Fortune 500 telecommunications firm provided the context for our study. Using a two-phase approach, the authors first captured the social network patterns of 268 managers from marketing, research and development (R&D), manufacturing, and other business functions that were involved in the new product development process. In addition, the reputational effectiveness of each person who was identified as a member of the network was measured. In the second phase, the authors examined the relational competencies (e.g., role-taking ability, interpersonal control, openness) of the managers who participated in Phase I of the research. As predicted, the results indicate that role-taking ability is related positively to a manager's reputational effectiveness. No support, however, was found for the relationship between interpersonal control and reputational effectiveness. Interestingly, the authors found evidence of an inverse relationship between openness and effectiveness. By sharing too much information?or alternatively information that does not relate to the task at hand?the reputational effectiveness of a manager is damaged. Importantly, the results reveal that the social network characteristics of a reputationally effective manager differ from those of less effective managers. Closeness centrality, a measure of the degree of access one has to other organizational members, was associated strongly with reputational effectiveness. The results demonstrate that managers who are successful in working across functions appreciate the cognitive and emotional perspectives of diverse constituents and develop relationship ties that provide them with ready access to others across the organization.

Abstract: In the time-left experiment (J. Gibbon & R. M. Church, 1981), animals are said to compare an expectation of a fixed delay to food, for one choice, with a decreasing delay expectation for the other, mentally representing both upcoming time to food and the difference between current time and upcoming time (the cognitive hypothesis). The results of 2 experiments support a simpler view: that animals choose according to the immediacies of reinforcement for each response at a time signaled by available time markers (the temporal control hypothesis). It is not necessary to assume that animals can either represent or subtract representations of times to food to explain the results of the time-left experiment.