In the Hearts of the Beasts: How American Behavioral Scientists Rediscovered the Emotions of Animals

Animals cannot use words to explain whether they feel emotions, and scientific opinion on the subject has been divided. Charles Darwin believed animals and humans share a common core of fear, anger, and affection. Today most researchers agree that animals experience comfort or pain. Around 1900 in the United States, however, where intelligence was the dominant interest in the lab and field, animal emotion began as an accidental question. Organisms ranging from insects to primates, already u...