"
Mr. Darwin gave us no help in this respect; and worse than this, he
contradicted himself so flatly as to show that he had very little
definite idea upon the subject at all. Thus in respect to the
winglessness of the Madeira beetles he wrote:-
"In some cases we might easily put down to disuse modifications of
structure, which are wholly or mainly due to natural selection. Mr.
Wollaston has discovered the remarkable fact that 200 beetles, out
of the 550 species (but more are now known) inhabiting Madeira, are
so far deficient in wings that they cannot fly; and that of the 29
endemic genera no less than 23 have all their species in this
condition! Several facts,--namely, that beetles in many parts of
the world are frequently blown out to sea and perish; that the
beetles in Madeira, as observed by Mr. Wollaston, lie much concealed
until the wind lulls and the sun shines; that the proportion of
wingless beetles is larger on the exposed Desertas than in Madeira
itself; and especially the extraordinary fact, so strongly insisted
on by Mr. Wollaston, that certain large groups of beetles, elsewhere
excessively numerous, which absolutely require the use of their
wings are here almost entirely absent;--these several considerations
make me believe that the wingless condition of so many Madeira
beetles is mainly due to the action of natural selection, COMBINED
PROBABLY WITH DISUSE [italics mine].
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