Chiara Passalacqua

Social eavesdropping in the domestic dog

Eavesdropping on third-party interactions has been observed in a number of species and is considered an important source of information in decision-making processes relating to fighting and mate choice. Human beings, however, use publicly available information flexibly in many different contexts including assessing others’ altruistic tendencies, which may in turn inform their choice of the most appropriate cooperative partner. We assessed whether dogs, Canis familiaris, were capable of discerning a generous versus selfish food-sharing interaction between humans, and investigated which communicative cues (voice versus gestures) may be more salient for them. Importantly a control condition was included to ascertain whether it was in fact the interaction between individuals as opposed to the direct actions of the actors that the dogs evaluated. We found that the dogs were capable of eavesdropping on human food-sharing interactions, and vocal communication was particularly important to convey the human’s cooperative versus noncooperative intent.

Gaze alternation in dogs and toddlers in an unsolvable task: evidence of an audience effect

Dogs have been shown to use human-directed gazing behaviour and gaze alternation in numerous contexts; however, it is still unclear whether this behaviour can be considered an intentional and referential communicative act. In the current study, adult dogs and preverbal toddlers were tested using the classic unsolvable task paradigm, but varying the attentional stance of the participating audience (the experimenter and the caregiver). The aims were to assess (1) whether dogs and toddlers would use gaze alternation behaviour in similar manners when the task became unsolvable, and (2) whether both dogs and toddlers would take into account the attentional stance of the audience when initiating a communicative interaction. Results indicated that both toddlers and dogs increased their gaze alternation behaviour between the apparatus and caregiver when the task became unsolvable, and toddlers also showed an increase in pointing behaviour. Furthermore, both species showed a capacity to take into account the attentional stance of the audience when manifesting gaze alternation behaviours towards them. Taken together, these results suggest that gaze alternation is both an intentional and referential communicative act and that both species can take into account the need for audience attention when communicating with them.

Comment on “Differential Sensitivity to Human Communication in Dogs, Wolves, and Human Infants”

Topál et al. (Reports, 4 September 2009, p. 1269) showed that dogs, like infants but unlike wolves, make perseverative search errors that can be explained by the use of ostensive cues from the experimenter. We suggest that a simpler learning process, local enhancement, can account for errors made by dogs.

Does Subjective Rating Reflect Behavioural Coding? Personality in 2 Month-Old Dog Puppies: An Open-Field Test and Adjective-Based Questionnaire

A number of studies have recently investigated personality traits in non-human species, with the dog gaining popularity as a subject species for research in this area. Recent research has shown the consistency of personality traits across both context and time for adult dogs, both when using questionnaire based methods of investigation and behavioural analyses of the dogs’ behaviour. However, only a few studies have assessed the correspondence between these two methods, with results varying considerably across studies. Furthermore, most studies have focused on adult dogs, despite the fact that an understanding of personality traits in young puppies may be important for research focusing on the genetic basis of personality traits. In the current study, we sought to evaluate the correspondence between a questionnaire based method and the in depth analyses of the behaviour of 2-month old puppies in an open-field test in which a number of both social and non-social stimuli were presented to the subjects. We further evaluated consistency of traits over time by re-testing a subset of puppies. The correspondence between methods was high and test- retest consistency (for the main trait) was also good using both evaluation methods. Results showed clear factors referring to the two main personality traits ‘extroversion,’ (i.e. the enthusiastic, exuberant approach to the stimuli) and ‘neuroticism,’ (i.e. the more cautious and fearful approach to the stimuli), potentially similar to the shyness-boldness dimension found in previous studies. Furthermore, both methods identified an ‘amicability’ dimension, expressing the positive interactions the pups directed at the humans stranger, and a ‘reservedness’ dimension which identified pups who largely chose not to interact with the stimuli, and were defined as quiet and not nosey in the questionnaire.

Breed, sex, and litter effects in 2-month old puppies’ behaviour in a standardised open-field test

A considerable number of studies have reported differences among dog breeds with respect to their genetic profile, cognitive abilities or personality traits. Each dog breed is normally treated as a homogeneous group, however, researchers have recently questioned whether the behavioural profile of modern breeds still reflects their historical function or if the intense divergent selective pressures and geographical barriers have created a more fragmented picture. The majority of studies attempting to assess and compare modern breeds’ personality focused on the evaluation of adult dogs where the potential effects of environmental/human factors on the dogs’ behaviour are hard to discern from their genetic heritage. In the following study, we aimed at investigating between- and within-breed differences in the personality of two-months-old puppies by direct behavioural observation of 377 puppies from 12 breeds. Results showed that there was no effect of sex, however both breed and litter, significantly affected all personality traits. Breed on average explained 10% of the variance, whereas the effect of litter was noticeably higher, explaining on average 23% of the variance. Taken together, our results suggest that breed does have some influence on personality traits, but they also highlight the importance of taking litter effects into account.