Page:Popular Science Monthly Volume 76.djvu/39

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DARWIN'S PLACE IN FUTURE BIOLOGY
35

interpretation of living nature did not originate with Darwin; that in fact it is as old as Greek philosophy at least. And because, so the view has run, he was not a discoverer in this but only a promoter, there was not sufficient ground upon which to build a truly immortal fame. Such fame, so it has been maintained, could be reached only through a supreme original discovery. Such a discovery was natural selection, the greatness of which consisted in its being the chief if not the sole explanation of evolution. Now, however, we are coming to see that Darwin erred, and that some of his followers have erred more, as to the power of natural selection in species transformation.[1]

  1. Since the manuscript of this essay went to the publisher, the celebrations of Darwin's birth have been held at Cambridge University. On one of the occasions Sir E. Ray Lankester is reported (Nature, July 1) to have said:

    "I think that the one thing about Charles Darwin which the large majority of British naturalists would wish to be to-day proclaimed, in the first place—with no doubtful or qualifying phrase—is that, in their judgment, after these fifty years of examination and testing, his 'theory of the origin of species by means of natural selection or the preservation of favored races in the struggle for life' remains whole and sound and convincing in spite of every attempt to upset it."

    Also in the meantime the paper by Drs. Raymond Pearl and Frank M. Surface, entitled "A Biometrical Study of Egg Production in the Domestic Fowl" (Bull. 110, part 1, Bureau of Animal Industry, U. S. Dept. of Agricul.) has reached me.

    From the mathematical treatment of the data collected through eight years of rigid selective breeding aimed at the improvement of egg production in chickens, the authors say: "It is shown that during the period covered by the statistics (1899-1907), which covers practically the whole period of the breeding experiment, there has been, apart from fluctuations up and down in individual years, a small but steady decrease in the mean or average annual egg production."

    "The percentage of extremely high layers (producing more than 195 eggs in the pullet year) in the flock decreased during the period from 1899 to 1907. The percentage of exceptionally poor layers (producing less than 45 eggs in the pullet year) in the flock increased during the same period."

    And concluding, the authors say: "It is shown that the intensity or stringency of selection became relatively greater during the progress of the experiment, though the absolute standard of selection remained the same. It is further shown that there is no evidence that the selective breeding practiced has improved the strain in respect to egg production. On the contrary, the data show that (a) the mean egg production has diminished during the experiment; (b) the variability in egg production has remained unchanged, and (c) in the last years of the experiment relatively slight environmental changes caused very marked changes in the flock productiveness. This is obviously inconsistent with the view that any particular type of egg production has in any way been fixed in a strain by breeding."

    Reading Lankester's statement in the light of this work at the Maine Agricultural Experiment Station, and of several other late researches of like import but less demonstrative value, I am, after the manner of Abraham Lincoln, reminded of a story: A Jersey farmer on his first visit to a menagerie came upon the dromedary. After scrutinizing for a long time in amazed silence