02400nas a2200193 4500008004100000245014000041210006900181520172100250653001601971653002701987653002302014653001402037653001802051653002502069100002202094700002402116700002302140856004302163 2018 eng d00aSeasonal variation in abundance and diversity of eavesdropping frog-biting midges (Diptera, Corethrellidae) in a neotropical rainforest0 aSeasonal variation in abundance and diversity of eavesdropping f3 a

In the tropics, precipitation patterns result in seasonal fluctuations in the abundance and distribution of plant and animal species. Tropical predators and parasites are therefore faced with seasonal changes in prey and host availability.
2. This study investigates the seasonal interaction among a specialised ectoparasite, eavesdropping frog-biting midges (Corethrella spp.), and their anuran hosts, examining how the abundance and diversity of the frog-biting midge community fluctuate between the rainy (host abundant) and dry (host sparse) seasons.
3. Midges were captured in both the rainy and dry seasons using acoustic playbacks of calls from a common frog species that breeds during the rainy season, the túngara frog (Engystomops, Physalaemus, pustulosus). During the dry season túngara frog choruses are absent. To explore seasonal shifts in host preference or changes in the midge community due to host specificity, midges were also captured using playbacks of calls from a frog that breeds during the dry season, the pug-nosed tree frog (Smilisca sila).
4. While the overall abundance of midges decreased in the dry season, only slight differences in the relative abundance between midge species were found. These results suggest that midge populations can shift between hosts as they become available across seasons, allowing adult populations of frog-biting midges to persist year-round. To overcome the challenge of detecting and localising different host species, it is proposed that frog-biting midges have evolved a generalised acoustic template, allowing them to respond to a broad range of available hosts, regardless of seasonal host composition.

10aCorethrella10aEngystomops pustulosus10afrog-biting midges10aphenology10aSmilisca sila10atropical seasonality1 aLegett, Henry, D.1 aBARANOV, VIKTOR, A.1 aBernal, Ximena, E. uhttp://doi.wiley.com/10.1111/een.1249202040nas a2200181 4500008004100000245011900041210006900160520139000229653002701619653002601646653001801672653002201690653001401712100002201726700002101748700002301769856006601792 2019 eng d00aSynchronized mating signals in a communication network: the challenge of avoiding predators while attracting mates0 aSynchronized mating signals in a communication network the chall3 a

Conspicuous mating signals attract mates but also expose signallers to predators and parasites. Signal evolution, therefore, is driven by conflicting selective pressures from multiple receivers, both target and non-target. Synchronization of mating signals, for example, is an evolutionary puzzle, given the assumed high cost of reduced female attraction when signals over- lap. Synchronization may be beneficial, however, if overlapping signals reduce attraction of non-target receivers. We investigate how signal synchro- nization is shaped by the trade-off between natural and sexual selection in two anuran species: pug-nosed tree frogs (Smilisca sila), in which males pro- duce mating calls in near-perfect synchrony, and túngara frogs (Engystomops pustulosus), in which males alternate their calls. To examine the trade-off imposed by signal synchronization, we conducted field and laboratory play- back experiments on eavesdropping enemies (bats and midges) and target receivers (female frogs). Our results suggest that, while synchronization can be a general strategy for signallers to reduce their exposure to eavesdrop- pers, relaxed selection by females for unsynchronized calls is key to the evolution and maintenance of signal synchrony. This study highlights the role of relaxed selection in our understanding of the origin of mating signals and displays.

10aacoustic communication10acommunication network10aeavesdroppers10arelaxed selection10asynchrony1 aLegett, Henry, D.1 aPage, Rachel, A.1 aBernal, Ximena, E. uhttps://royalsocietypublishing.org/doi/10.1098/rspb.2019.1067