The Descent of Man

make the loudest or most continuous noise
would gain partners before those which were
less noisy, so that their organs have probably
been gained through sexual selection. It is instructive
to reflect on the wonderful diversity of
the means for producing sound, possessed by
the males alone, or by both sexes, in no less
than six Orders. We thus learn how effectual
sexual selection has been in leading to modifications
which sometimes, as with the Homoptera,
relate to important parts of the organisation.
From the reasons assigned in the last chapter, it
is probable that the great horns possessed by
the males of many Lamellicorn, and some other
beetles, have been acquired as ornaments. From
the small size of insects, we are apt to undervalue
their appearance. If we could imagine a
male Chalcosoma (Fig. 16), with its polished
bronzed coat of mail, and its vast complex
horns, magnified to the size of a horse, or even