The Expression of the Emotions in Man and Animals Science" concluded that "although some parts are a little tedious, from the amount of minute detail required, there is throughout so much of acute observation and amusing anecdote as to render it perhaps more attractive to general readers than any of Mr. Darwin's previous work". Eric Korn, in the "London Review of Books", describes how the book was claimed, and he argues subverted, by Margaret Mead and her "sympathisers", and then presented afresh by Paul Ekman. Ekman had collected pro-Darwin, anti-Mead evidence, Korn wrote, for the universality of human facial expression of emotions. Darwin, suggests Korn, avoided unsettling the Victorian
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