Genetics and the Origin of Species natural selection, and speciation throughout his book to explain habits of populations and the resulting effects on their genetic behavior. The book explains evolution in depth as a process over time that accounts for the diversity of all life on Earth. The study of evolution was present, but greatly neglected at the time. Dobzhansky illustrates that evolution regarding the origin and nature of species during this time in history was deemed mysterious, but had expanding potential for progress to be made in its field. In Darwin's theory of natural selection, more organisms are produced than can survive. Some have variations
On the Origin of Species deal with counter-arguments raised. The third edition came out in 1861, with a number of sentences rewritten or added and an introductory appendix, "An Historical Sketch of the Recent Progress of Opinion on the Origin of Species", while the fourth in 1866 had further revisions. The fifth edition, published on 10 February 1869, incorporated more changes and for the first time included the phrase "survival of the fittest", which had been coined by the philosopher Herbert Spencer in his "Principles of Biology" (1864). In January 1871, George Jackson Mivart's "On the Genesis of Species" listed detailed arguments against natural selection,