Eva Ricci

Owners as a secure base for their dogs

A modified version of the Ainsworth Strange Situation Test was used to analyse 40 dog–owner pairs in order to assess whether owners can represent a secure base for their dogs. The Wilcoxon test revealed significant differences between owner and stranger for protest at separation (whining), contact maintenance effect (proximity, attention seeking and physical contact) and secure base effect (exploration, individual play and social play). The results suggest that dogs behave similarly to children towards the mothers and to chimpanzees towards human caretakers in the Ainsworth Strange Situation Test: owners are the preferred recipient of affiliative behaviours and, in their absence, dogs show behaviours indicative of distress. After reunion with the owner, dogs show an increase in social behaviours towards him/her. Dogs did not show fear of the stranger, and it was regarded as a normal behaviour for adult well-socialized dogs. Until now whether owners represented a secure base for their dogs was debated, due to controversial results. This study found that dogs play and explore more when owners were present, suggesting that owners can represent a secure base for their dogs. Therefore, according to Bowlby’s definition, dogs are linked to their owners by an attachment bond.

Behavioral Thermoregulation in a Gregarious Lemur, Eulemur collaris: Effects of Climatic and Dietary-Related Factors

Primates deal with fluctuations of the thermal environment by both physiological and behavioral mechanisms of thermoregulation. In this article we focus on non-hibernating lemurs, which are hypometabolic and have to cope with a seasonal environment. Behavioral thermoregulation has received little attention compared with specific physiological adaptations to seasonality, i.e., hibernation and torpor, which characterize a number of lemurs. We investigated the role of seasonality and dietary-related factors in determining frequencies of resting, social and postural thermoregulation, and microhabitat selection in collared lemurs, Eulemur collaris. We observed two groups of collared lemurs over a 14-month period in the littoral forest of Sainte Luce, Southern Madagascar. Frequencies of total resting and time spent in huddling, prone, and curled postures were collected via 5-min instantaneous sampling. Microhabitat selection was evaluated as the proportion of time spent in the upper canopy as compared with other layers. Climatic variables were recorded by automatic data loggers, while dietary variables were derived from phenological data and nutritional analyses of the ingested food items. We weighted the combined effects of climatic and dietary variables on the different types of behavioral thermoregulation by means of canonical correlation analysis. The model with the strongest canonical correlation included a first root representing mainly feeding time, day length, and ambient temperature and a second root representing diet quality and height of feeding trees. The output indicated that collared lemurs adapt to thermal and dietary-related metabolic stress by adjusting resting time, social, and postural thermoregulation.