The voyage of the Beagle (1845)
On the origin of species (1859)
The descent of man, and selection in relation to sex (1871)
The expression of the emotions in man and animals (1872).
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From so simple a beginning : the four great books of Charles Darwin by Charles Darwin. ISBN 0393061345. Published by W. W. Norton in 2006. Publication and catalogue information, links to buy online and reader comments.
