Emotion in animals teeth in aggressive action. A domestic dog's simple tail wag may be used in subtly different ways to convey many meanings as illustrated in Darwin's "The Expression of the Emotions in Man and Animals" published in 1872. Evidence for emotions in animals has been primarily anecdotal, from individuals who interact with pets or captive animals on a regular basis. However, critics of animals having emotions often suggest that anthropomorphism is a motivating factor in the interpretation of the observed behaviours. Much of the debate is caused by the difficulty in defining emotions and the cognitive requirements thought necessary for animals
The Expression of the Emotions in Man and Animals and a "geologizing expedition" – but actually spent some of his time re-exploring the old haunts of his undergraduate days. On the day of the coronation, 28 June 1838, Darwin was in Edinburgh. A few weeks later, he opened a private notebook with philosophical and psychological speculation – the "M Notebook" – and, over the next three months, filled it with his thoughts about possible interactions of hereditary factors with the mental and behavioural aspects of life.It should also be noted that Darwin made his first attempt at autobiography in August 1838. The critical importance of the "M Notebook" has