Contributions to the Theory of Natural Selection: A Series of EssaysWallace, Alfred Russel
Science
Contributions to the Theory of Natural Selection: A Series of Essays
Wallace, Alfred Russel
Natural selection
But this resemblance, close as it is, would be of little use if the
habits of the insect did not accord with it. If the butterfly sat upon
leaves or upon flowers, or opened its wings so as to expose the upper
surface, or exposed and moved its head and antennae as many other
butterflies do, its disguise would be of little avail. We might be sure,
however, from the analogy of many other cases, that the habits of the
insect are such as still further to aid its deceptive garb; but we are
not obliged to make any such supposition, since I myself had the good
fortune to observe scores of Kallima paralekta, in Sumatra, and to
capture many of them, and can vouch for the accuracy of the following
details. These butterflies frequent dry forests and fly very swiftly.
They were never seen to settle on a flower or a green leaf, but were
many times lost sight of in a bush or tree of dead leaves. On such
occasions they were generally searched for in vain, for while gazing
intently at the very spot where one had disappeared, it would often
suddenly dart out, and again vanish twenty or fifty yards further on. On
one or two occasions the insect was detected reposing, and it could then
be seen how completely it assimilates itself to the surrounding leaves.
It sits on a nearly upright twig, the wings fitting closely back to
back, concealing the antennae and head, which are drawn up between their
bases. The little tails of the hind wing touch the branch, and form a
perfect stalk to the leaf, which is supported in its place by the claws
of the middle pair of feet, which are slender and inconspicuous. The
irregular outline of the wings gives exactly the perspective effect of a
shrivelled leaf. We thus have size, colour, form, markings, and habits,
all combining together to produce a disguise which may be said to be
absolutely perfect; and the protection which it affords is sufficiently
indicated by the abundance of the individuals that possess it.
Public-domain text, read in full here on John Shaqi.
Reviews
Reviews
No reviews yet
Be the first to share your thoughts on this work.
Join the Discussion
Join the discussion
Sign in to leave a comment or review.
Sign InorCreate an account