The Origin of Species

First published in 1859, this landmark book on evolutionary biology was not the first to deal with the subject, but it went on to become a sensation—and a controversial one for many religious people who could not reconcile Darwin’s science with their faith. Darwin worked on the book for over 20 years before its publication. The radical crux of his scientific theory was the idea of natural selection, which meant that chance, not a divine Creator, played a great role in humanity's advancement and that individuals who weren't physically able to adapt with the greater populace died off.