01996nas a2200277 4500008004100000022001300041245015400054210006900208260001600277300001300293490000700306520106800313653002701381653003101408653003501439653001801474653001901492653001901511653001901530100002001549700002401569700002101593700002101614700001701635856006601652 2007 eng d a0003347200aBehavioural specialization among populations of the acoustically orienting parasitoid fly Ormia ochracea utilizing different cricket species as hosts0 aBehavioural specialization among populations of the acoustically cJan-01-2007 a99 - 1040 v733 a

Tightly coupled evolutionary associations between parasites and their hosts are well known. What is less well characterized is the behavioural specialization of parasites that exploit different hosts in different parts of the parasite’s geographical range. Here we examine behavioural specialization among populations of a parasitoid fly, Ormia ochracea, that exploit different host species of crickets in different parts of the fly’s range. We conducted a field experiment to compare phonotactic attraction of flies from Florida, Texas, California and Hawaii (U.S.A.) to the songs of their local host species of cricket versus their attraction to the songs of species of crickets utilized as hosts elsewhere within the flies’ range. We found strong behavioural specialization of fly populations, with preferential phonotaxis towards the song of the local host species of cricket. These results suggest strong behavioural specialization of flies, but that specialization does not constrain or preclude the rapid adoption of novel hosts.

10aacoustic communication10abehavioural specialization10adiptera-orthoptera coevolution10aeavesdropping10ahost selection10aOrmia ochracea10aparasitoid fly1 aGray, David, A.1 aBanuelos, Christina1 aWalker, Sean, E.1 aCade, William H.1 aZuk, Marlene uhttp://linkinghub.elsevier.com/retrieve/pii/S000334720600393902192nas 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

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.

10aGryllus10aOrmia ochracea10aparasitoid10aspecialization10avariation1 aSakaguchi, Kelly, M.1 aGray, David, A. uhttp://linkinghub.elsevier.com/retrieve/pii/S000334721100027301774nas a2200157 4500008004100000022001300041245005100054210004700105260001600152300001400168490000700182520131900189100002001508700002201528856006601550 2001 eng d a0003347200aIs cricket courtship song condition dependent?0 acricket courtship song condition dependent cJan-11-2001 a871 - 8770 v623 a

Females of the Texas trilling field cricket, Gryllus texensis, show mating preferences based on male courtship song. To test experimentally the condition dependence of courtship song, we attempted to manipulate male condition via the diet. When the diet was manipulated at the adult moult, there was no effect on subsequent male courtship song or male condition measured as residual mass. When the diet was manipulated three moults prior to the adult moult, there was a significant effect on male residual mass, but no differences in courtship song were observed. To gain a second measure of condition in the diet-manipulated-as-nymphs group, we extracted their fat using petroleum ether in a refluxing Soxhlet apparatus. Crickets reared on the poor diet showed a clear relationship between the residual mass measure of condition and condition measured as energetic fat reserve, whereas the two measures of condition were unrelated in crickets reared on the good diet. Courtship song was unrelated to diet, fat reserve or residual mass. We conclude that courtship song does not reflect male condition in the laboratory despite its energetic cost. When given a mating opportunity it is probably in the evolutionary interest of males in poor condition to signal at as high a rate as males in good condition.

1 aGray, David, A.1 aEckhardt, Gillian uhttp://linkinghub.elsevier.com/retrieve/pii/S000334720191825100625nas a2200145 4500008004100000022001400041245012500055210006900180260001600249300001600265490000800281100002600289700002000315856014400335 2001 eng d a0179-161300aDivergence between the Courtship Songs of the Field Crickets Gryllus texensis and Gryllus rubens (Orthoptera, Gryllidae)0 aDivergence between the Courtship Songs of the Field Crickets Gry cMay-12-2003 a1075 - 10850 v1071 aFitzpatrick, Mark, J.1 aGray, David, A. uhttp://doi.wiley.com/10.1046/j.1439-0310.2001.00730.xhttps://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1046%2Fj.1439-0310.2001.00730.x