Abstract: Many animals appear to monitor changes in other individuals' dominance ranks and social relationships and to track changes in them. However, it is not known whether they also track changes in very transient relationships. Rapid recognition of a temporary separation between a dominant male and a sexually receptive female, for example, should be adaptive in species where subordinate males use opportunistic strategies to achieve mating success. Dominant male baboons (Papio hamadryas ursinus) form sexual consortships with oestrous females that are characterized by mate guarding and close proximity. To assess whether subordinate males track temporary changes in the status of other males' consortships, we conducted playback experiments using a two-speaker paradigm. In the test condition, subjects heard the consort male's grunts played from one speaker and his consort female's copulation call played from a speaker approximately 40 m away. This sequence suggested that the male and female had temporarily separated and that the female was mating with another male. In a control trial, subjects heard another dominant male's grunts played from one speaker and the female's copulation call played from the other. In a second control trial, conducted within 24 h after the consortship had ended, subjects again heard the consort male's grunt and the female's copulation call played from separate speakers. As predicted, subjects responded strongly only in the test condition. Eavesdropping upon the temporal and spatial juxtaposition of other individuals' vocalizations may be one strategy by which male baboons achieve sneaky matings.

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: The papers in this special issue examine the relationship between social and ecological cognition in primates. We refer to the intersection of these two domains as socioecological cognition. Examples of socioecological cognition include socially learned predator alarm calls and socially sensitive foraging decisions. In this review we consider how primate cognition may have been shaped by the interaction of social and ecological influences in their evolutionary history. The ability to remember distant, out-of-sight locations is an ancient one, shared by many mammals and widespread among primates. It seems some monkeys and apes have evolved the ability to form more complex representations of resources, integrating “what-where-how much” information. This ability allowed anthropoids to live in larger, more cohesive groups by minimizing competition for limited resources between group members. As group size increased, however, competition for resources also increased, selecting for enhanced social skills. Enhanced social skills in turn made a more sophisticated relationship to the environment possible. The interaction of social and ecological influences created a spiraling effect in the evolution of primate intelligence. In contrast, lemurs may not have evolved the ability to form complex representations which would allow them to consider the size and location of resources. This lack in lemur ecological cognition may restrict the size of frugivorous lemur social groups, thereby limiting the complexity of lemur social life. In this special issue, we have brought together two review papers, five field studies, and one laboratory study to investigate the interaction of social and ecological factors in relation to foraging. Our goal is to stimulate research that considers social and ecological factors acting together on cognitive evolution, rather than in isolation. Cross fertilization of experimental and observational studies from captivity and the field is important for increasing our understanding of this relationship.

Abstract: We studied seasonal changes in fecal cortisol metabolites (FCM), which have been widely used as indicators of stress, in a population of Pyrenean chamois (Rupicapra pyrenaica pyrenaica) in the Cadí Range of northeastern Spain. We collected fecal samples from 2001 to 2003 in 3 particular locations with different altitudes and male or female presence, and we analyzed them for FCM and fecal nitrogen as an indicator of diet quality. We observed a clear seasonal pattern, with the highest FCM in winter, and we obtained correlations between FCM and monthly mean minimum temperatures and fecal nitrogen. We observed no effects of tourism presence, trophy hunting, or rut season on FCM. Analysis of cortisol metabolites in feces can be a good measure of winter stress in Pyrenean chamois.