Abstract: Social learning is taxonomically widespread and can provide distinct behavioural advantages, such as in finding food or avoiding predators more efficiently. Although extensively studied in bony fishes, no such empirical evidence exists for cartilaginous fishes. Our aim in this study was to experimentally investigate the social learning capabilities of juvenile lemon sharks, Negaprion brevirostris. We designed a novel food task, where sharks were required to enter a start zone and subsequently make physical contact with a target in order to receive a food reward. Naive sharks were then able to interact with and observe (a) pre-trained sharks, that is, ‘demonstrators’, or (b) sharks with no previous experience, that is, ‘sham demonstrators’. On completion, observer sharks were then isolated and tested individually in a similar task. During the exposure phase observers paired with ‘demonstrator’ sharks performed a greater number of task-related behaviours and made significantly more transitions from the start zone to the target, than observers paired with ‘sham demonstrators’. When tested in isolation, observers previously paired with ‘demonstrator’ sharks completed a greater number of trials and made contact with the target significantly more often than observers previously paired with ‘sham demonstrators’. Such experience also tended to result in faster overall task performance. These results indicate that juvenile lemon sharks, like numerous other animals, are capable of using socially derived information to learn about novel features in their environment. The results likely have important implications for behavioural processes, ecotourism and fisheries.

Abstract: The present study investigated the influence of temperament on long-term recall and extinction of 2 instrumental tasks in 26 horses. In the first task (backward task), horses learned to walk backward, using commands given by an experimenter, in order to obtain a food reward. In the second task (active avoidance task), horses had to cross an obstacle after a bell rang in order to avoid emission of an air puff. Twenty-two months after acquisition, horses exhibited perfect recall performance in both tasks. Accordingly, no influence of temperament on recall performance could be observed for either task. In contrast, in the absence of positive or negative outcomes, the horses’ ability to extinguish their response to either task was highly variable. Resistance to extinction was related to some indicators of temperament: The most fearful horses tended to be the most resistant to extinction in the backward task, while the least sensitive horses tended to be the most resistant to extinction in the active avoidance task. These findings reveal extensive long-term memory abilities in horses and suggest an influence of temperament on learning processes other than acquisition.

Abstract: The study examines whether untrained dogs and infants take their caregiver’s visual experience into account when communicating with them. Fifteen adult dogs and 15 one-year-old infants were brought into play with their caregivers with one of their own toys. The caregiver gave the toy to the experimenter, who, in different conditions, placed it either above or under one of two containers, with both the infant or dog and the caregiver witnessing the positioning; in a third condition, the caregiver left the room before the toy was placed under one of the two containers and later returned. Afterwards, for each condition, the caregiver asked the participant to indicate the location of the toy. Neither dogs nor infants—untrained to the use of the partner’s knowledge state—showed much difference of behaviour between the three conditions. However, dogs showed more persistence for most behaviours (gaze at the owner, gaze at the toy and gaze alternation) and conditions, suggesting that the situation made more demands on dogs’ communicative behaviours than on those of infants. When all deictic behaviours of infants (arm points towards the toy and gaze at the toy) were taken into account, dogs and infants did not differ. Phylogeny, early experience and ontogeny may all play a role in the ways that both species communicate with adult humans.