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
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,