02606nas a2200265 4500008004100000245007200041210006900113300001600182490000700198520178400205653001001989653002201999653003302021653001202054653003602066653002502102100001902127700002302146700002602169700002302195700002202218700002202240700002002262856005802282 2018 eng d00aPhoretic dispersal influences parasite population genetic structure0 aPhoretic dispersal influences parasite population genetic struct a2770 - 27790 v273 a

Abstract
Dispersal is a fundamental component of the life history of most species. Dispersal influences fitness, population dynamics, gene flow, genetic drift and population genetic structure. Even small differences in dispersal can alter ecological interactions and trigger an evolutionary cascade. Linking such ecological processes with evolu- tionary patterns is difficult, but can be carried out in the proper comparative con- text. Here, we investigate how differences in phoretic dispersal influence the population genetic structure of two different parasites of the same host species. We focus on two species of host-specific feather lice (Phthiraptera: Ischnocera) that co-occur on feral rock pigeons (Columba livia). Although these lice are ecologically very similar, “wing lice” (Columbicola columbae) disperse phoretically by “hitchhiking” on pigeon flies (Diptera: Hippoboscidae), while “body lice” (Campanulotes compar) do not. Differences in the phoretic dispersal of these species are thought to underlie observed differences in host specificity, as well as the degree of host–parasite cospeciation. These ecological and macroevolutionary patterns suggest that body lice should exhibit more genetic differentiation than wing lice. We tested this pre- diction among lice on individual birds and among lice on birds from three pigeon flocks. We found higher levels of genetic differentiation in body lice compared to wing lice at two spatial scales. Our results indicate that differences in phoretic dis- persal can explain microevolutionary differences in population genetic structure and are consistent with macroevolutionary differences in the degree of host–parasite cospeciation.

10abirds10aCommunity ecology10ahost–parasite interactions10ainsects10apopulation genetics—empirical10aspecies interactions1 aDiBlasi, Emily1 aJohnson, Kevin, P.1 aStringham, Sydney, A.1 aHansen, Angela, N.1 aBeach, Andrew, B.1 aClayton, Dale, H.1 aBush, Sarah, E. uhttps://onlinelibrary.wiley.com/doi/10.1111/mec.14719