Abstract: Dogs' ability to recognise cues of human visual attention was studied in different experiments. Study 1 was designed to test the dogs' responsiveness to their owner's tape-recorded verbal commands (Down!) while the Instructor (who was the owner of the dog) was facing either the dog or a human partner or none of them, or was visually separated from the dog. Results show that dogs were more ready to follow the command if the Instructor attended them during instruction compared to situations when the Instructor faced the human partner or was out of sight of the dog. Importantly, however, dogs showed intermediate performance when the Instructor was orienting into 'empty space' during the re-played verbal commands. This suggests that dogs are able to differentiate the focus of human attention. In Study 2 the same dogs were offered the possibility to beg for food from two unfamiliar humans whose visual attention (i.e. facing the dog or turning away) was systematically varied. The dogs' preference for choosing the attentive person shows that dogs are capable of using visual cues of attention to evaluate the human actors' responsiveness to solicit food-sharing. The dogs' ability to understand the communicatory nature of the situations is discussed in terms of their social cognitive skills and unique evolutionary history.

Abstract: Dogs are more skillful than great apes at a number of tasks in which they must read human communicative signals indicating the location of hidden food. In this study, we found that wolves who were raised by humans do not show these same skills, whereas domestic dog puppies only a few weeks old, even those that have had little human contact, do show these skills. These findings suggest that during the process of domestication, dogs have been selected for a set of social-cognitive abilities that enable them to communicate with humans in unique ways.

Abstract: In previous studies great apes have shown little ability to locate hidden food using a physical marker placed by a human directly on the target location. In this study, we hypothesized that the perceptual similarity between an iconic cue and the hidden reward (baited container) would help apes to infer the location of the food. In the first two experiments, we found that if an iconic cue is given in addition to a spatial/indexical cue – e.g., picture or replica of a banana placed on the target location – apes (chimpanzees, bonobos, orangutans, gorillas) as a group performed above chance. However, we also found in two further experiments that when iconic cues were given on their own without spatial/indexical information (iconic cue held up by human with no diagnostic spatial/indexical information), the apes were back to chance performance. Our overall conclusion is that although iconic information helps apes in the process of searching hidden food, the poor performance found in the last two experiments is due to apes' lack of understanding of the informative (cooperative) communicative intention of the experimenter.

Abstract: The relative importance of an internal sense of direction based on inertial cues and landmark piloting for small-scale navigation by White King pigeons (Columba livia) was investigated in an arena search task. Two groups of pigeons differed in whether they had access to visual cues outside the arena. In Experiment 1, pigeons were given experience with 2 different entrances and all pigeons transferred accurate searching to novel entrances. Explicit disorientation before entering did not affect accuracy. In Experiments 2-4, landmarks and inertial cues were put in conflict or tested 1 at a time. Pigeons tended to follow the landmarks in a conflict situation but could use an internal sense of direction to search when landmarks were unavailable.

Abstract: Object permanence in Eurasian jays (Garrulus glandarius) was investigated using a complete version of the Uzgiris and Hunt scale 1. Nine hand-raised jays were studied, divided into two groups according to their different developmental stages (experiment 1, older jays: 2-3 months old, n = 4; experiment 2, younger jays: 15 days old, n = 5). In the first experiment, we investigated whether older jays could achieve piagetian stage 6 of object permanence. Tasks were administered in a fixed sequence (1-15) according to the protocols used in other avian species. The aim of the second experiment was to check whether testing very young jays before their development of “neophobia” could influence the achievement times of piagetian stages. Furthermore, in this experiment tasks were administered randomly to investigate whether the jays' achievement of stage 6 follows a fixed sequence related to the development of specific cognitive abilities. All jays tested in experiments 1 and 2 fully achieved piagetian stage 6 and no “A not B” errors were observed. Performance on visible displacement tasks was better than performance on invisible ones. The results of experiment 2 show that “neophobia” affected the response of jays in terms of achievement times; the older jays in experiment 1 took longer to pass all the tasks when compared with the younger, less neophobic, jays in experiment 2. With regard to the achieving order, jays followed a fixed sequence of acquisition in experiment 2, even if tasks were administered randomly, with the exception of one subject. The results of these experiments support the idea that piagetian stages of cognitive development exist in avian species and that they progress through relatively fixed sequences.