Recently, one of my former students, André Morrill, got a paper accepted in the Canadian Journal of Zoology as first author on explaining covariation between ectoparasitic mites and endoparasitic eugregarine protozoans of Lestes damselflies. Many previous researchers have addressed the extent to which either mites or gregarines are associated with reduction in fitness of their insect hosts. In these singular studies examining just one parasite taxa or species, there is the implicit assumption that any patterns discovered are attributable to the parasite under study, and not some other parasites species that has not been monitored or enumerated. André’s work shows that there are reasons to expect these parasites might covary. The link to the paper for those interested can be found here. André also has recently senior authored a paper in International Journal of Parasitology concerning how a Poisson distribution of random parasite encounter and a normal distribution of host condition can combine through a few simple rules of condition-linked immunity to produce the oft-seen and oft-cited negative binomial distribution of parasites on hosts. This research suggests that we need not invoke environmental heterogeneity in parasite infective stages to explain aggregated distributions on hosts; such occurrences, however, will make parasite distributions even more aggregated. Read the abstract of that paper here.
Professor & student