In contrast to the African great apes, orangutans (Pongo spp.) are semisolitary: Individuals are often on their own, but form aggregations more often than expected by chance. These temporary aggregations provide social benefits such as mating opportunities. When fruit availability is high, costs of aggregating should be lower, because competition is less pronounced. Therefore, average party size is expected to be higher when fruit availability is high. This hypothesis would also explain why orangutans in highly fruit-productive habitats on Sumatra are more gregarious than in the usually less productive habitats of Borneo. Here, we describe the aggregation behavior of orangutans in less productive Sumatran habitats (Sikundur and Batang Toru), and compare results with those of previously surveyed field sites. Orangutans in Sikundur were more likely to form parties when fruit availability was higher, but the size of daily parties was not significantly affected by fruit availability. With regard to between-site comparisons, average party sizes of females and alone time of parous females in Sikundur and Batang Toru were substantially lower than those for two previously surveyed Sumatran sites, and both fall in the range of values for Bornean sites. Our results indicate that the assessment of orangutans on Sumatra as being more social than those on Borneo needs revision. Instead, between-site differences in sociality seem to reflect differences in average fruit availability.

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Attention may be swiftly and automatically tuned to emotional expressions in social primates, as has been demonstrated in humans, bonobos, and macaques, and with mixed evidence in chimpanzees, where rapid detection of emotional expressions is thought to aid in navigating their social environment. Compared to the other great apes, orangutans are considered semi-solitary, but still form temporary social parties in which sensitivity to others’ emotional expressions may be beneficial. The current study investigated whether implicit emotion-biased attention is also present in orangutans (Pongo pygmaeus). We trained six orangutans on the dot-probe paradigm: an established paradigm used in comparative studies which measures reaction time in response to a probe replacing emotional and neutral stimuli. Emotional stimuli consisted of scenes depicting conspecifics having sex, playing, grooming, yawning, or displaying aggression. These scenes were contrasted with neutral scenes showing conspecifics with a neutral face and body posture. Using Bayesian mixed modeling, we found no evidence for an overall emotion bias in this species. When looking at emotion categories separately, we also did not find substantial biases. We discuss the absence of an implicit attention bias for emotional expressions in orangutans in relation to the existing primate literature, and the methodological limitations of the task. Furthermore, we reconsider the emotional stimuli used in this study and their biological relevance.

Attractiveness is an important aspect of human society. Attractive people enjoy multiple societal privileges and are assigned positive personality traits, and both men and women find attractiveness important when it comes to partner choice. Our universal preference for beauty might be reflected in implicit perception of human faces. In a series of three studies, we use Bayesian methods to investigate whether attractiveness or attractive traits modulate implicit attention and gaze cuing in a large community sample. In Experiment 1, we used a dot-probe task to measure attentional bias toward attractive faces. The results demonstrate that participants reacted faster when the probe appeared behind an attractive face but not when it appeared behind an unattractive face, suggesting that specifically attractive faces captured attention. In Experiment 2, we used a similar method to test whether facial symmetry, an oftenmentioned characteristic of attractive faces, modulated attention. However, we found no such effect. In Experiment 3, we used a gaze-cuing task to test whether participants were more likely to follow the gaze of attractive faces, but no such effect was found. To conclude, attractiveness affects our implicit attention toward faces, but this does not seem to extend to gaze cuing.

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Anecdotes in animal behaviour"It is just an anecdote", is an often-heard critique to scientists describing animal behaviour that has not been reported before. But what if this anecdote is a qualitative, rich observation, showing a truly unique behaviour or event that can change the way we think about a species? If an ethologist or another animal expert observes unforeseen behaviour that may be of interest, it is a loss for the field if this observation remains unreported and as a result forgotten. This is especially the case for very rare behaviours or unusual circumstances under which certain behaviours occur.In the past, anecdotal accounts have brought behaviours such as hunting, tool use, infanticide and tactical deception (these examples concern primates) to our attention, and have motivated researchers to study these behaviours quantitatively. Nowadays, such narrative accounts of unique behaviours are on a stark decline (Ramsay & Teichroeb, 2019).In order to safeguard valuable anecdotes in animal behaviour and prevent them from oblivion, at Behaviour, we deem it highly valuable to make them available again to the scientific community, and predict that by doing so, readers might recognize the behaviour that is described and, ideally, reply to these in a 'commentary / reflection'. This will help to contextualize the anecdote better, recognize its scope and generality, and stimulate the design of new directions of study based upon these anecdotes. Eventually, the initial report of a certain anecdote could, together with commentaries and more evidence, become a collection centred around a certain topic (for example: "Tactical deception in primates" (Whiten & Byrne, 1988)).We hereby invite scholars who have anecdotal evidence of unique behaviour in any species, to submit these as a commentary to Behaviour, and if possible, accompanied by a video or photograph. The narrative will be re-

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Examines attitude changes occurring in companies since the mid‐1980s through job disruptions and redundancies, and suggests leaders do not realize that companies are not running as efficiently as they should. Wilson Learning has studied group emphasis since 1985 and suggests that creating a sense of collaboration (or post‐heroic leadership) is a necessity for organizations to survive. Lists capacities required for people to meet this challenge and concludes managers must shift away from traditional top down hierarchical structuring.