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Wallace, Alfred Russel, 1823-1913

"Darwinism (1889)"



_Useless or non-adaptive Characters._
Many naturalists seem to be of opinion that a considerable number of the
characters which distinguish species are of no service whatever to their
possessors, and therefore cannot have been produced or increased by
natural selection. Professors Bronn and Broca have urged this objection
on the continent. In America, Dr. Cope, the well-known palaeontologist,
has long since put forth the same objection, declaring that non-adaptive
characters are as numerous as those which are adaptive; but he differs
completely from most who hold the same general opinion in considering
that they occur chiefly "in the characters of the classes, orders,
families, and other higher groups;" and the objection, therefore, is
quite distinct from that in which it is urged that "specific characters"
are mostly useless. More recently, Professor G.J. Romanes has urged this
difficulty in his paper on "Physiological Selection" (_Journ. Linn.
Soc._, vol. xix. pp. 338, 344). He says that the characters "which serve
to distinguish allied species are frequently, if not usually, of a kind
with which natural selection can have had nothing to do," being without
any utilitarian significance.


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