Abstract: Some researchers have proposed that natural selection has given rise in humans to one or more adaptations for altruistically punishing on behalf of other individuals who have been treated unfairly, even when the punisher has no chance of benefiting via reciprocity or benefits to kin. However, empirical support for the altruistic punishment hypothesis depends on results from experiments that are vulnerable to potentially important experimental artefacts. Here, we searched for evidence of altruistic punishment in an experiment that precluded these artefacts. In so doing, we found that victims of unfairness punished transgressors, whereas witnesses of unfairness did not. Furthermore, witnesses’ emotional reactions to unfairness were characterized by envy of the unfair individual's selfish gains rather than by moralistic anger towards the unfair behaviour. In a second experiment run independently in two separate samples, we found that previous evidence for altruistic punishment plausibly resulted from affective forecasting error—that is, limitations on humans’ abilities to accurately simulate how they would feel in hypothetical situations. Together, these findings suggest that the case for altruistic punishment in humans—a view that has gained increasing attention in the biological and social sciences—has been overstated.

Abstract: Animal communication generally occurs in the environment of a network of several potential signallers and receivers. Within a network environment, it is possible to gain relative information about conspecifics by eavesdropping on signalling interactions. We presented male great tits with the opportunity to gain such information by simulating singing interactions using two loudspeakers. Interactions were presented so that relevant information was not available in the absolute singing behaviour of either individual, only in the relative timing of their songs in the interaction as a whole. We then assayed the information extracted by focal males by subsequently introducing one of the 'interactants' (i.e. loudspeakers) into the territory of the focal male. Focal males responded with a reduced song output to males that had just 'lost' an interaction. Focal males did not respond significantly differently to 'winners' as compared with intruders recently involved in an interaction that contained no consistent information. Focal males also responded by switching song types more often when encountering males that had recently been involved in a low-intensity interaction. These results provide the clearest evidence yet that male songbirds extract information from signal interactions between conspecifics in the field.

Abstract: Chimpanzee (Pan troglodytes) societies are typically characterized as physically aggressive, male-bonded and male-dominated. Their close relatives, the bonobos (Pan paniscus), differ in startling and significant ways. For instance, female bonobos bond with one another, form coalitions, and dominate males. A pattern of reluctance to consider, let alone acknowledge, female dominance in bonobos exists, however. Because both species are equally “man's” closest relative, the bonobo social system complicates models of human evolution that have historically been based upon referents that are male and chimpanzee-like. The bonobo evidence suggests that models of human evolution must be reformulated such that they also accommodate: real and meaningful female bonds; the possibility of systematic female dominance over males; female mating strategies which encompass extra-group paternities; hunting and meat distribution by females; the importance of the sharing of plant foods; affinitive inter-community interactions; males that do not stalk and attack and are not territorial; and flexible social relationships in which philopatry does not necessarily predict bonding pattern.

Abstract: The aim of this comparative study was to gain more information about the excretion of steroid hormones in farm animals. This should help to establish or improve non-invasive steroid monitoring procedures, especially in zoo and wildlife animals. Over a period of 4 h the 14C-steroid hormones (3.7 MBq) progesterone (three females), testosterone (three males), cortisol and oestrone (two males, two females) were infused intravenously in sheep, ponies and pigs. Faeces were collected immediately after defecation. Urine was sampled via a permanent catheter in females and after spontaneous urination in males. A total of 88 +/- 10% (mean +/- SD) of the administered radioactivity was recovered. Considerable interspecies differences were measured both in the amounts of steroid metabolites excreted via faeces or urine and the time course of excretion. Progesterone and oestrone in ewes, and progesterone in mares were excreted mainly in the faeces (over 75%). The primary route of excretion of all other 14C-steroids was via the urine but to a different extent. In general, sheep showed the highest degree of faecal excretion and pigs the least. The highest radioactivity in urine (per mmol creatinine) was observed during the infusion or in one of the next two samples thereafter, whereas in faeces it was measured about 12 h (sheep), 24 h (ponies) or 48 h (pigs) after the end of the infusion. Thereafter the radioactivity declined and reached background levels within 2-3 weeks. In faeces, steroid metabolites were present mainly in an unconjugated form, but in blood and urine as conjugates. Mean retention time of faecal radioactivity suggested that the passage rate of digesta (duodenum to rectum) played an important role in the time course of the excretion of steroids. The information derived from this investigation could improve the precision of sampling as well as the extraction of steroids from the faeces. Furthermore, the study demonstrates that it should be possible to establish methods for measuring faecal androgen and cortisol metabolites for assessing male reproductive endocrinology and stress in animals.

Abstract: Stress responses play an important role in allowing animals to cope with challenges. Glucocorticoids, key elements in the neuroendocrine stress axis, are traditionally measured as a parameter for welfare assessment. As blood sample collection itself disturbs an animal, non-invasive or minimal invasive methods have gained importance for assessing stress. In horses saliva and faeces are most frequently used. Faecal samples offer the advantage that they can be collected easily and stress-free. In faecal samples circulating hormone levels are integrated over a certain period of time. As a consequence faecal glucocorticoid metabolites represent the cumulative secretion and they are less affected by short episodic fluctuations of hormone secretion.
However, in order to gain reliable information about an animal’s adrenocortical activity, certain criteria have to be met: Depending whether the impact of acute or chronic stressors is assessed, frequent sampling might be necessary whereas in other cases, single samples will suffice. Background knowledge regarding the metabolism and excretion of glucocorticoids is essential and a careful validation is obligatory. In addition, this presentation will address analytical issues regarding sample storage, extraction procedures, and immunoassays and various examples of a successful application in equids will be given. Applied properly, non-invasive techniques to monitor stress hormones are a useful tool for animal welfare assessment.