Abstract: In a wide range of animal species, males coerce females to mate with them, either by physically forcing them to mate, by harassing them until they mate or by punishing persistent refusal to mate. The first section of this paper argues that the possibility of forced copulation can generate arms races between males and females that may have substantial costs to both sexes. In the second section, it is suggested that sexual harassment commonly represents a `war of attrition' between the sexes; existing game theory models that may apply to sexual conflict over mating decisions are reviewed. The third section develops a simple prospective model for the evolution of intimidation by punishment in situations where males can raise the probability that females will accept their advances in future by punishing them for refusal to mate. Where the benefits of sexual coercion to males are high, all three male strategies may develop to a point where they have substantial costs to females. In the final section, evidence that female behaviour is adapted to minimizing these costs is reviewed.

Abstract: This paper reviews the reasons why domestic dogs make good models to investigate cognitive processes related to social living and describes experimental approaches that can be adopted to investigate such processes in dogs. Domestic dogs are suitable models for investigating social cognition skills for three broad reasons. First, dogs originated from wolves, social animals that engage in a number of co-operative behaviours, such as hunting and that may have evolved cognitive abilities that help them predict and interpret the actions of other animals. Second, during domestication dogs are likely to have been selected for mental adaptations for their roles in human society such as herding or companionship. Third, domestic dogs live in a human world and “enculturation” may facilitate the development of relevant mental skills in dogs. Studies of social cognition in animals commonly use experimental paradigms originally developed for pre-verbal human infants. Preferential gaze, for example, can be used as a measure of attention or “surprise” in studies using expectancy violation. This approach has been used to demonstrate simple numerical competence in dogs. Dogs also readily use both conspecific and human social signals (e.g. looking or pointing) as information sources to locate hidden rewards such as food or favourite toys. Such abilities make dogs particularly good models for investigating perspective-taking tasks, where animals are required to discriminate between apparently knowledgeable and apparently ignorant informants.

Abstract: Relatively little is known about the relationship between social behavior and specific cognitive abilities of the chicken. It is uncertain whether dominant birds have a cognitive advantage over subordinate birds that might facilitate their superior position in the social hierarchy. Likewise, it is unknown whether subordinate birds compete successfully with higher ranking birds because their cognitive capacities compensate for physical deficits. In this study, the relationship between the chicken's position in the dominance hierarchy and its performance on a cognitive task was explored. Ten pairs of New Hampshire domestic roosters (Gallus gallus) were observed to determine dominance or subordinance within dyads. All birds were then trained and tested on a visual discrimination learning task. Discriminative stimuli were orange and green plastic discs. Correct stimuli (orange or green) were randomly assigned to birds. Placement of the discs (left or right of center) was also randomly assigned and counterbalanced to avoid a side bias. Birds were rewarded with food for pecking at the correct disc. Criterion for task completion was 80% correct responses on three consecutive test sessions or 86% correct on two consecutive sessions. All subjects met the test criterion. The number of trials to criterion was compared between dominant and subordinate birds using a paired t-test. No difference was found in performance between dominant and subordinate birds (p > 0.05) suggesting that in chickens, ability to learn a novel visual discrimination task is not well correlated with rank. Additional studies, particularly using different learning paradigms, are needed to confirm these results.

Abstract: Flehmen behaviour in Welsh pony (Equus caballus) mares and foals living on pasture was observed during 807 h of focal sampling. A series of flehmens performed at one site was defined as a flehmen incident. Colts exhibited flehmen incidents and performed flehmen more frequently during an incident than did fillies or mares. Filies exhibited flehmen incidents more frequently than did mares, but did not flehmen more frequently during an incident. Colts exhibited a peak frequency of performing flehmen and of flehmen incidents during weeks 1-4 with a subsequent linear decrease in frequency up to weeks 17-20. Usually, flehmen occurred without the subject having had direct contact of the nostrils, lips, or tongue with a possible stimulant. Twenty-six per cent of the flehmen incidents occurred during or after urination by another pony. Seven per cent of the incidents occurred during or after urination by the pony showing flehmen.