The Expression of the Emotions in Man and Animals Man and Animals", a collection of 37 papers with current research on the subject. Free e-book versions: The Expression of the Emotions in Man and Animals The Expression of the Emotions in Man and Animals is Charles Darwin's third major work of evolutionary theory, following "On the Origin of Species" (1859) and "The Descent of Man" (1871). Originally intended as a section of "The Descent of Man", it was published separately in 1872 and concerns the biological aspects of emotional life. In this book, Darwin sets out some early ideas about behavioural genetics, and explores the animal origins of such
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