Wings

[Doug Yanega]

>I would think that the best empirical evidence of purpose in butterfly wings
>would be the huge cost associated with metamorphosis.

Many Orthopteroids have wings, and they have pretty simple metamorphosis.
The *ancestors* of butterflies had wings, so butterflies do. You can't
answer anything that way.
        You want to look for *proximate* explanations, then examine species
which have lost their wings, or simply don't fly, and ask "What is
different about the ecology of these insects?". In general, you'll find
they are insects which have either lost the need to disperse altogether
(there are MANY high-altitude or island endemics lacking wings) or have one
sex or life stage which does disperse, while the other does not. This does
obviously include several Lepidoptera, including things like the gypsy moth
(females have wings but don't use them), so questions of energetics of
metamorphosis fall far short.

Peace,

Doug Yanega    Depto. de Biologia Geral, Instituto de Ciencias Biologicas,
Univ. Fed. de Minas Gerais, Cx.P. 486, 30.161-970 Belo Horizonte, MG   BRAZIL
phone: 031-449-2579, fax: 031-499-2567  (from U.S., prefix 011-55)
                  http://www.icb.ufmg.br/~dyanega/
  "There are some enterprises in which a careful disorderliness
        is the true method" - Herman Melville, Moby Dick, Chap. 82