By 1839, Darwin had married Emma Wedgwood. Ruse indicates that at this time Darwin was gaining experience from the Downe where he lived (5). He committed his life to science, though he succumbed to Chagas&nbsp.disease for a long time. It was at this time that he uncovered the issue of the origin of species and what came to be known as natural selection in the Darwinian Theory. In the late 1850s, Darwin was able to compile his pieces to his famous book, The Origin of Species by Means of Natural Selection. Critics of the book were witnessed, though Darwin kept publishing more works. After a long period of illness, Darwin passed on leaving eight kids. He is greatly remembered for his contribution to evolution theories though he was the first to apply the thoughts of plants and animal descent. He indeed contributed greatly to the field of Science.