the
world had already acknowledged that "pure" Darwinism or natural
selection cannot explain the origin of new organs or new forms. And now
Mendelism destroys the other supposed foundation for biological
evolution, by showing that small variations cannot be accumulated into
large differences equal in value to a unit character or a new species.
Thus the whole foundation of biological evolution has been completely
undermined by these new discoveries; and were it not for the wide-spread
credence the evolutionary theory has already received, and the
intellectual momentum it has acquired tending to carry it on by its
inertia into the future, it could be only a very short time now before
the elaborate treatises attempting to orientate with it all the facts of
religion and history would have to be consigned to the shelves labeled,
"Of Historic Interest." For as Bateson remarked in his recent address as
President before the British Association at Melbourne, Australia, the
new knowledge of heredity shows that whatever evolution there is occurs
by loss of factors and not by gain, and that in this way the progress of
science is "destroying much that till lately passed for gospel."[32]
[Footnote 32: In commenting on these views of Bateson, Prof. S.C. Holmes,
of the University of California, well speaks of them as "an illustration
of _the bankruptcy of present evolutionary theory."--Science_, September
3, 1915.]
V
Let us sum up the situation. We began this chapter with the question,
Have new kinds of plants and animals originated in modern times
comparable in all essential respects with the idea of true species?
The answer of modern science is reluctantly obtained, but it is a
negative. De Vries and others have indeed originated new kinds that were
loudly hailed as new species, and are doubtless as deserving of specific
rank as many already listed for years in the treatises of specialists.
Indeed there is every reason to believe that almost countless numbers of
our taxonomic species have originated from common ancestral originals.
But as these so-called species are now known to be freely or moderately
cross fertile with other related species, their hybrids following the
ordinary laws of Mendelian inheritance, we see that they are not true
species but mere analytic varieties.
In short, we now know that our taxonomic classifications have been
marked off on altogether too narrow lines. This has tended greatly to
confuse th
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