Origin of Metamorphosis

First off, I would like to state that I am a biochemist not a biologist
and evolutionary biology is not my main field of activity. Anyway, this
brings me to my first question. I was recently on answers.yahoo and
someone asked about the origin of metamorphosis. I realized that in
this area I hadn't a clue as to the evolutionary origin of
metamorphosis in insects and other invertebrates. If anyone would be
willing to espouse knowledge on the subject please by all means
enlighten me.


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