Most birds have feather lice that are passed from parents to offspring, such that louse species are often restricted to particular hosts with which they share a long co-evolutionary history. The African indigobirds (genus Vidua) are host-specific brood parasites, reproducing only by laying eggs in the nests of certain estrildid finch host species. These parasitic birds and their hosts are members of two distinct families (Viduidae and Estrildidae) that diverged from a common ancestor millions of years ago, yet they have continue to have intimate contact in the host nest. This presents an excellent opportunity to examine evolutionary interactions between birds and parasitic lice. With support from the NSF Office of International Science and Engineering, this research will test whether indigobirds carry the lice of their respective host species, suggesting that associations between lice and birds are determined primarily by the ecology of louse transmission. If so, patterns of lice infestation may lend insight into the diversification of indigobirds, in which rapid speciation has apparently followed the colonization of new host species. On the other hand, if indigobirds and hosts each have their own unique lice, then associations between lice and birds may be constrained by the adaptation of lice to specific host lineages.
