Measuring empathic responses in animals

Domestic animals may be frequently exposed to situations in which they witness the distress or pain of conspecifics and the extent to which they are affected by this will depend on their capacity for empathy. Empathy encompasses two partially distinct sets of processes concerned with the emotional and cognitive systems. The term, empathy, is therefore used to describe both relatively simple processes, such as physiological and behavioural matching; and more complex interactions between emotional and cognitive perspective taking systems. Most previous attempts to measure empathic responsiveness in animals have not distinguished between responses primarily relevant to the situation of the observer and those primarily relevant to the situation of the conspecific. Only the latter can be considered empathic. However, even during well-controlled studies, behavioural or physiological responses to conspecific pain or distress may indicate nothing more than interest or arousal. To demonstrate a truly empathic response to the plight of another, experimenters must also show that a valenced (positive or negative), and therefore emotional, component is present. Such studies are vital to the fundamental question of the extent to which animals are capable of empathic responsiveness, and to determine how the welfare of domestic animals might be affected by the social environment. In this review we will consider evidence for the existence of the capacity for emotional empathy, in its broadest sense, in a variety of non-human species and offer direction on future work of relevance to the welfare implications of coping in large groups.