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 only the last chapter still to write. In September the main title still included ""An essay on the origin of species and varieties"", but Darwin now proposed dropping "varieties". With Murray's persuasion, the title was eventually agreed as "On the Origin of Species", with the title page adding "by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life". In this extended title (and elsewhere in the book) Darwin used the biological term ""races"" interchangeably with ""varieties"", meaning varieties within a species. He used the term broadly, and as well as discussions of "the several