Charles Darwin 
The Expression of the Emotions in Man and Animals (Barnes & Noble Digital Library) 

This edition includes a modern introduction and a list of suggested further reading.


 
In
The Expression of the Emotions in Man and Animals Charles Darwin argued that emotions put forward by facial expressions were the products of natural selection. He compared modern facial expressions in various people and found the same basic movements regardless of the person’s ethnic or cultural background. He also compared human and animal expression and found many startling similarities. He thought facial expression was not a learned behavior but somehow innate. This condition could only be explained by common descent, which was a rather radical idea for the time.

About the author

Charles Darwin is the author of one of the most controversial and influential works in Western thought,
The Origin of the Species. At age twenty-two, Darwin, who had dropped out of medical school in Edinburgh, became the gentleman companion to the moody, irascible Captain Robert Fitz Roy. Although his father had wanted him to become a pastor, Darwin’s journey on the H.M.S.
Beagle led him to instead become a naturalist and the forerunner of evolutionary theory.