On the Tendency of Species to form Varieties; and on the Perpetuation of Varieties and Species by Natural Means of Selection Letter" from Darwin to Asa Gray. This was the first announcement of the Darwin – Wallace theory of evolution by natural selection; the papers appeared in print on 20 August 1858. The presentation of the papers spurred Darwin to write a condensed "abstract" of his "big book" on "Natural Selection". This was published in November 1859 as "On the Origin of Species". On the voyage of the "Beagle" the young Charles Darwin took a break between graduating and starting his career as a clergyman to study the natural history of South America, an interest he had developed at the University
Genetics and the Origin of Species revive the Jesup lectures, a series that had involved some notable lecturers in the past. It was back-dated so that Dobzhansky's lectures became the first in the series. The Columbia University Biological Series was also revived, and when "Genetics and the Origin of Species" was published in October 1937 it became the 11th volume in that series. Three main editions were published, in 1937, 1941 and 1951, each with significant changes. Dobzhansky considered "Genetics of the Evolutionary Process" (1970) a fourth edition, but one so much changed that it needed a new title. "Genetics and the Origin of Species" has