In the October issue of PLoS Biology Joron et al. report that a "supergene" locus controls color patterning in three Heliconius butterfly species.
Joron et al. (2006) A conserved supergene locus controls colour pattern diversity in Heliconius butterflies. PLoS Biology 4(10):e303.
notes on evolutionary biology papers/programs and other stuff: a non-frequent approach