The Expression of the Emotions in Man and Animals in the James-Lange theory of emotions, James develops Darwin's emphasis on the physical aspects, including the visceral (autonomically mediated) components of emotion. In Walter Cannon's "Bodily Changes in Pain, Hunger, Fear and Rage" (1915), Cannon introduces the famous phrase "fight or flight response", formulating emotions in terms of strategies for interpersonal behaviour. More recent psychological theories of emotion have been set out in the Papez-Maclean hypothesis and the Two factor theory of emotion. On 24 January 1895, James Crichton-Browne delivered a notable lecture in Dumfries, Scotland "On Emotional Expression", presenting some of his reservations about Darwin's views. Crichton-Browne argued for
Emotion in animals as when rolling and rubbing. Therefore, purring can be generally considered as an indicator of "pleasure" in cats. Low pitched bleating in sheep has been associated with some positive-valence situations, as they are produced by males as an estrus female is approaching or by lactating mothers while licking and nursing their lambs. The argument that animals experience emotions is sometimes rejected due to a lack of evidence, and those who don't believe in the idea of animal intelligence, often argue that anthropomorphism plays a role in individuals' perspectives. Those who reject that animals have the capacity to experience emotion do