Page:Popular Science Monthly Volume 75.djvu/541

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541
THE ORIGIN OF SPECIES

THE ARGUMENT FOR ORGANIC EVOLUTION BEFORE THE ORIGIN OF SPECIES
By Professor ARTHUR O. LOVEJOY

THE UNIVERSITY OF MISSOURI

II

IN the former part of this historical inquiry, it was shown that four of the arguments which rapidly made converts to the theory of evolution after 1859 rested upon principles of scientific method and facts of anatomy and physiology which were entirely familiar much more than fifteen years before that date. A similar examination must now be made of four more of the most important "evidences of evolution." Here again it will appear that the facts were known at least as early as 1844, and that their evolutionary implications were pointed out by Robert Chambers, Herbert Spencer or other pre-Darwinian writers. It will also appear that the flaws and gaps in the evidence which could be plausibly exhibited by the opponents of the theory during those fifteen years were, for the most part, not removed by the "Origin of Species," nor for a number of years subsequent to its publication. Substantially, whatever force the arguments for the transformist conception of the origin of the specific characters of organisms had after 1859, they had before; and whatever weaknesses they had before that memorable year, they still had after it. In presenting proof of this I shall, as before, indicate by direct citations the manner in which the arguments were used by the early Darwinians, and then point out the parallel reasonings in the evolutionists of the earlier period.

5. The Argument from the Sequence of Types in Paleontology.—The nature of this argument is, of course, too familiar to need exposition. The value which Huxley attached to it in 1863 is shown by a passage in his "Lectures on the Phenomena of Organic Nature ":

If you regard the whole series of stratified rocks . . . constituting the only record we have of a most prodigious lapse of time;—if you observe in these successive strata of rocks successive groups of animals arising and dying out, a constant succession giving you the same kind of impression, as you travel from one group of strata to another as you would have in travelling from one country to another; . . . when you look at this wonderful history and ask what it means, it is only a paltering with words if you are offered the reply, "They were so created." But if, on the other hand, you look on all forms of organized beings as the results of the gradual modification of a primitive type, the facts receive a meaning and you see that these older conditions are the necessary predecessors of the present. Viewed in this light the facts of pale-