Female preferences for males producing their calls just ahead of their neighbours, leader preferences, are common in acoustically communicating insects and anurans. While these preferences have been well studied, their evolutionary origins remain unclear. We tested whether females gain a fitness benefit by mating with leading males in
More Like this
-
more » « less
Abstract Neoconocephalus ensiger katydids. We mated leading and following males with random females and measured the number and quality ofF 1, the number ofF 2and the heritability of the preferred male trait. We found that females mating with leaders and followers did not differ in the number ofF 1orF 2offspring. Females mating with leading males had offspring that were in better condition than those mating with following males suggesting a benefit in the form of higher quality offspring. We found no evidence that the male trait, the production of leading calls, was heritable. This suggests that there is no genetic correlate for the production of leading calls and that the fitness benefit gained by females must be a direct benefit, potentially mediated by seminal proteins. The presence of benefits indicates that leader preference is adaptive inN. ensiger , which may explain the evolutionary origin of leader preference; further tests are required to determine whether fitness benefits can explain the phylogenetic distribution of leader preference inNeoconocephalus . The absence of heritability will prevent leader preference from becoming coupled with or exaggerating the male trait and prevent females from gaining a ‘sexy‐sons’ benefit, weakening the overall selection for leader preference. -
more » « less
Summary Environmental variation can have profound and direct effects on fitness, fecundity, and host–symbiont interactions. Replication rates of microbes within arthropod hosts, for example, are correlated with incubation temperature but less is known about the influence of host–symbiont dynamics on environmental preference. Hence, we conducted thermal preference (
T p) assays and tested if infection status and genetic variation in endosymbiont bacteriumWolbachia affected temperature choice ofDrosophila melanogaster Wolbachia preferred lower temperatures compared with uninfectedDrosophila . Moreover,T pvaried with respect to three investigatedWolbachia variants (w Mel,w MelCS, andw MelPop). While uninfected individuals preferred 24.4°C, we found significant shifts of −1.2°C inw Mel‐ and −4°C in flies infected either withw MelCS orw MelPop. We, therefore, postulate thatWolbachia‐ associatedT pvariation within a host species might represent a behavioural accommodation to host–symbiont interactions and trigger behavioural self‐medication and bacterial titre regulation by the host.
