On the Origin of Species is a work of natural history by Charles Darwin. It was published in 1859 as On the Origin
of Species by Means of Natural Selection: or, The Preservation of Favoured Races in the Struggle for Life.
Darwin argues for the existence of a "single
progenitor" of life on earth which is an irrevocable form far removed from any current type.
'Natural selection' works unconsciously to the advantage only of the
individual and its progeny within a species, and is never in order to benefit other species. It operates through descent and relies on variation: that individual organisms vary in differing degrees and across a spectrum of characterisctics from parent-generation.
Unlike 'natural selection', 'artifical selection' demonstrates that it is possible within few generations to breed plants and creatures whose selected characteristics have advantages for one particular breeding.
Darwin always insisted that his theory on evolution is entirely on biological reference.