By Professor T. H. MORGAN
WE have come together to-day to consider Darwin's influence on zoology. It is a hazardous task to pretend to estimate the influence of any event on the course of history so long as we can not know what the outcome had been otherwise. But to this at least we can testify, that it is the general belief of zoologists to-day that Darwin's influence in bringing about the acceptance of the theory of evolution marks a turning point in the history of their science, and I shall attempt to justify this opinion by pointing out the condition of zoology before Darwin and its subsequent course of development after 1859.
To the zoologist Darwin was above all else a zoologist. It is true he interested himself greatly in geology, but he does not stand as a leader of that science; he carried out many experiments with plants and wrote some important botanical books, and here the zoologist will yield second place to his brother, the botanist. Darwin wrote on the "Descent of Man," he studied the expression of the emotions and carried out physiological work along several lines, yet I should not rank him preeminently an anthropologist, a psychologist or a physiologist any more than a paleontologist or a botanist.
In the mind of the general public Darwinism stands to-day for evolution. The establishment of the theory of evolution is generally accepted as Darwin's chief contribution to human thought, and while Darwin did not originate this idea that forms the framework of our modern thinking, yet by general accord its acceptance is attributable, and justly so, to Darwin.
To the zoologist Darwinism means more especially evolution accounted for by the theory of natural selection, yet also many other things, to which I shall refer in the proper place.
But I shall attempt this afternoon, before all else, to convince you that the loyalty that every man of science feels towards Darwin is something greater than any special theory. I shall call it the spirit of Darwinism, the point of view, the method, the procedure, of Darwin.
In order that we may form some idea of Darwin's influence on zoology, let us examine the condition of that science prior to 1859 to
- A lecture on "Darwin's Influence on Zoology," delivered at Columbia University, February 26, 1909.