Abstract: Teaching is a powerful form of social learning, but there is little systematic evidence that it occurs in species other than humans. Using long-term video archives the foraging behaviors by mother Atlantic spotted dolphins (Stenella frontalis) were observed when their calves were present and when their calves were not present, including in the presence of non-calf conspecifics. The nine mothers we observed chased prey significantly longer and made significantly more referential body-orienting movements in the direction of the prey during foraging events when their calves were present than when their calves were not present, regardless of whether they were foraging alone or with another non-calf dolphin. Although further research into the potential consequences for the naive calves is still warranted, these data based on the maternal foraging behavior are suggestive of teaching as a social-learning mechanism in nonhuman animals.

Abstract: Abstract: Understanding animals" abilities to cooperate with and learn from each other has been an active field of research in recent years. One important basis for all types of social interactions is the disposition of animals to pay attention to each other-a factor often neglected in discussions and experiments. Since attention differs between species as well as between individuals, it is likely to influence the amount and type of information different species and/or observers may extract from conspecifics in any given situation. Here, we carried out a standardized comparative study on attention towards a model demonstrating food-related behavior in keas, dogs and children. In a series of experimental sessions, individuals watched different conspecific models while searching, manipulating and feeding. Visual access to the demonstration was provided by two observation holes, which allowed us to determine exactly how often and for how long observers watched the model. We found profound differences in the factors that influence attention within as well as between the tested species. This study suggests that attention should be incorporated as an important variable when testing species in social situations.

Abstract: Abstract: Hemispheric asymmetry in emotional perception has been put forward by different theories as the right hemisphere theory or the valence theory. But no consensus was found about the role played by both hemispheres. So, in order to test the different theories, we investigated preferential use of one eye in red-capped mangabeys, at the individual as well as at the group level. In this study we investigated the influence of the emotional value of stimuli on the direction and strength of visual preference of 14 red-capped mangabeys. Temporal stability of the bias of use of a given eye was evaluated by comparing our current results to those obtained 2.5 months previously. Two experimental devices, a tube and a box, tested five different stimuli: four food types varying in palatability and a neutral stimulus. The subjects" food preferences were evaluated before testing the laterality. The mangabeys used their left eyes predominantly at the group level for the tube task. The majority of the subjects showed a visual preference at the individual level for the box task, but this bias was not present at the group level. As the palatability of the stimuli increased, the number of lateralized subjects and the number of subjects using preferentially their left eye increased. Similarly, the strength of laterality was related to food preference. Strength of laterality was significantly higher for subjects using their left eye than for subjects using their right eye. Preferential use of a given eye was stable over short periods 2.5 months later. Our data agree with reports on visual laterality for other species. Our results support the valence theory of a hemispheric sharing of control of emotions in relation to their emotional value.

Abstract: Laterality is now known to be an ubiquitous phenomenon among the vertebrates. Particularly, laterality of auditory processing has been demonstrated in a variety of species, especially songbirds and primates. Such a hemispheric specialization has been shown to depend on factors such as sound structure, species specificity and types of stimuli. Much less is known on the possible influence of social familiarity although a few studies suggest such an influence. Here we tested the influence of the degree of familiarity on the laterality of the auditory response in the domestic horse. This species is known for its social system and shows visible reactions to sounds, with one or two ears moving towards a sound source. By comparing such responses to the playback of different conspecific whinnies (group member, neighbor and stranger), we could demonstrate a clear left hemisphere (LH) preference for familiar neighbor calls while no preference was found for group member and stranger calls. Yet, we found an opposite pattern of ear side preference for neighbor versus stranger calls. These results are, to our knowledge, the first to demonstrate auditory laterality in an ungulate species. They open further lines of thought on the influence of the social “value” of calls and the listener's arousal on auditory processing and laterality.

Abstract: Abstract  Although primates have often been found to co-orient visually with other individuals, members of these same species have usually failed to use co-orientation to find hidden food in object-choice experiments. This presents an evolutionary puzzle: what is the function of co-orientation if it is not used for a function as basic as locating resources? Co-orientation responses have not been systematically investigated in object-choice experiments, and requiring co-orientation with humans (as is typical in object-choice tasks) may underestimate other species’ abilities. Using an object-choice task with conspecific models depicted in photographs, we provide experimental evidence that two lemur species (Eulemur fulvus, n = 4, and Eulemur macaco, n = 2) co-orient with conspecifics. Secondly, by analysing together two measures that have traditionally been examined separately, we show that lemurs’ gaze following behaviour and ultimate choice are closely linked. Individuals were more likely to choose correctly after having looked in the same direction as the model, and thus chose objects correctly more often than chance. We propose a candidate system for the evolutionary origins of more complex gaze following: ‘gaze priming.’