On the Origin of Species Darwin's ideas with those of Lamarck and Goethe while still reflecting the spirit of "Naturphilosophie". Their ambitious programme to reconstruct the evolutionary history of life was joined by Huxley and supported by discoveries in palaeontology. Haeckel used embryology extensively in his recapitulation theory, which embodied a progressive, almost linear model of evolution. Darwin was cautious about such histories, and had already noted that von Baer's laws of embryology supported his idea of complex branching. Asa Gray promoted and defended "Origin" against those American naturalists with an idealist approach, notably Louis Agassiz who viewed every species as a distinct fixed unit
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