You sound familiar: carrion crows can differentiate between the calls of known and unknown heterospecifics

In group-living animals, it is adaptive to recognize conspecifics on the basis of familiarity or group membership as it allows association with preferred social partners and avoidance of competitors. However, animals do not only associate with conspecifics but also with heterospecifics, for example in mixed-species flocks. Consequently, between-species recognition, based either on familiarity or even individual recognition, is likely to be beneficial. The extent to which animals can distinguish between familiar and unfamiliar heterospecifics is currently unclear. In the present study, we investigated the ability of eight carrion crows to differentiate between the voices and calls of familiar and unfamiliar humans and jackdaws. The crows responded significantly more often to unfamiliar than familiar human playbacks and, conversely, responded more to familiar than unfamiliar jackdaw calls. Our results provide the first evidence that birds can discriminate between familiar and unfamiliar heterospecific individuals using auditory stimuli.     

The Changing Value of Skill Utilisation: Interactions with Job Demands on Job Satisfaction and Absenteeism

Opportunities to learn and apply new skills are generally considered a favourable job characteristic, but can there be too much of a good thing? In this paper, we draw on vitamin and resource perspectives to investigate a more nuanced perspective on where, when and why skill utilisation delivers value as a resource. Specifically, we examine whether skill utilisation exhibits non-linear relationships with job satisfaction and absenteeism in the presence of two different job demands: task workload, which captures the quantitative demands of work, and surface acting, which captures the qualitative demands of work. Using data from 278 hospital employees, we found that surface acting moderated the non-linear relationship between skill utilisation and absenteeism. Specifically, the relationship between skill utilisation and absenteeism became increasingly positive when surface acting was high, but not when surface acting was low. Interestingly, the linear relationship between skill utilisation and job satisfaction was less positive when surface acting was high. Task workload did not interact with skill utilisation to predict employee outcomes. Our findings highlight complexities in the relationship between job resources and demands and show that the value of skill utilisation changes under demanding conditions.     

The specificity of terms affects conditional reasoning

Conditional inferences can be phrased with unspecific terms (“If a person is on a diet, then the person loses weight. A person is on a diet. The person loses weight”) or specific terms (“If Anna is on a diet, then Anna loses weight. Anna is on a diet. Anna loses weight”). We investigate whether the specificity of terms affects people's acceptance of inferences. In Experiment 1, inferences with specific terms received higher acceptance ratings than inferences with unspecific terms. In Experiments 2 and 3, we used the same problems as in Experiment 1 but also problems with unspecific terms in the conditional and specific terms in the categorical and vice versa. When the conditional and the categorical had the same specificity, results were as in Experiment 1. When the specificity of the conditional and the categorical mismatched, acceptance ratings were lower. Our results illustrate the importance of phrasing on reasoning.