02192nas a2200217   4500008004100000022001300041245012200054210006900176260001600245300001400261490000700275520150200282653001201784653001901796653001501815653001901830653001401849100002501863700002001888856006601908       2011                        eng d  a0003347200aHost song selection by an acoustically orienting parasitoid fly exploiting a multispecies assemblage of cricket hosts0 aHost song selection by an acoustically orienting parasitoid fly   cJan-04-2011  a851 - 8580 v813 a<p>Specialization by predators, parasites and parasitoids is often viewed as adaptive because specialization will usually increase search efficiency for suitable hosts (prey). Although many studies have documented interspecific variation in the degree of host specialization, few studies have examined intraspecific variation in specialization among different populations exploiting different numbers of hosts, and even fewer have specifically examined variation in behavioural specialization. Here we examine the acoustic preferences of a parasitoid fly, Ormia ochracea, which attacks several Gryllus species of field crickets by using the male cricket song to locate hosts. All previous studies with this system have examined fly song preferences in populations of flies that primarily exploit a single host species of cricket. Here we tested a population of flies that naturally parasitizes multiple cricket species. We found significant interspecific host song preferences; however, as predicted, the strength of preference was reduced compared to single-host populations of flies. We also examined fly song selection for intraspecific variants of two of the cricket host species; flies showed significant preference for intraspecific song variants of one of the two cricket species. Our results demonstrate that the degree of behavioural specialization, in a very highly specialized fly, nevertheless shows interpopulation variation consistent with the numbers of host species utilized.</p>
10aGryllus10aOrmia ochracea10aparasitoid10aspecialization10avariation1 aSakaguchi, Kelly, M.1 aGray, David, A.  uhttp://linkinghub.elsevier.com/retrieve/pii/S0003347211000273