RESEARCH Open Access Path

analyses of cross-sectional and longitudinal data suggest that variability in natural communities of blood-associatedparasites is derived fromhost characteristics andnot interspecific interactions Carmit Cohen1, Monica Einav1 and Hadas Hawlena1,2* Background: The parasite composition of wild host individuals often impacts their behavior and physiology, and the transmission dynamics of pathogenic species thereby determines disease risk in natural communities. Yet, the determinants of parasite composition in natural communities are still obscure. In particular, three fundamental questions remain open: (1) what are the relative roles of host and environmental characteristics compared with direct interactions between parasites in determining the community composition of parasites? (2) do these determinants affect parasites belonging to the same guild and those belonging to different guilds in similar manners? and (3) can cross-sectional and longitudinal analyses work interchangeably in detecting community determinants? Our study was designed to answer these three questions in a natural community of rodents and their fleas, ticks, and two vector-borne bacteria. Methods: We sampled a natural population of Gerbillus andersoni rodents and their blood-associated parasites on tw