Lewontin 9700941 We now know that natural selection can result in exquisitely precise convergence at the molecular level. One area in which molecular convergence has been demonstrated is vision. Opsins, the proteins that are primarily responsible for determining the spectral sensitivity of a photoreceptor, have undergone convergent evolution in response to selection for similar sensitivities. The purpose of this research is to extend these studies by investigating opsin evolution in a group of butterflies famous for mimicry. This study tests whether or not opsin amino acid sequences are correlated with the convergently acquired mimetic morphologies. Because butterfly eyes are in part like morphologies will have resulted in the evolution of like opsins. The methods employed will be to finish sequencing the opsin genes of pairs of mimetic Heliconius butterflies, and then to examine the pattern of opsin amino acid substitution by mapping the opsin sequences on a recent phylogeny of this group based on mitochondrial DNA.
