HILL, R.I.; Univ. of California, Berkeley: Morphology and locomotor mimicry in ithomiine butterflies (Nymphalidae)

Neotropical ithomiine butterflies (Nymphalidae) exhibit rampant convergent evolution of color patterns. It is not uncommon in lowland rainforest to find up to nine color patterns at a site, with several species from 2-5 genera exhibiting each pattern. This color pattern convergence is an excellent example of M�llerian mimicry involving mutually distasteful species. Unpalatable butterflies in general have associated kinematic and morphological traits such as slow flight, low wing beat frequency and rearward displaced center of body mass. Mimicry among unpalatable butterflies is known to extend to flight morphology and kinematics in Heliconius butterflies, but the generality of this �locomotor� mimicry has not been tested. Morphological measurements of 38 species of ithomiine butterflies from an assemblage in eastern Ecuador containing eight mimetic color patterns, or mimicry rings, are used to examine whether locomotor mimicry exists in the ithomiines. Do species that share color pattern also share flight morphology? Principal components and discriminant function analyses are used to assess which morphological traits best discriminate among mimicry rings. Comparative analyses using a molecular phylogeny are also used to examine scaling relationships and morphological trait evolution.