symbioses

[Sooka]

Hi there,
        I am heading to the Peruvian Amazon in the spring for a field trip.
I have to write a paper for this class and would like to do it on something
about butterflies and their relationships with other animals and plants.
For example, something like the monarch's use of the milkweed plant and the
viceroys mimicry.  Does anyone have any suggestions about S. American
species, or know of any good books.

Thanks,
Faith