Helinski Michelle E H, Harrington Laura C
Department of Entomology, Cornell University, Ithaca, NY 14853.
Behav Ecol Sociobiol. 2012 Aug 1;66(8):1131-1140. doi: 10.1007/s00265-012-1365-9.
Sexual harassment studies in insects suggest that females can incur several kinds of costs from male harassment and mating. Here, we examined direct and indirect costs of male harassment on components of female fitness in the predominantly monandrous mosquito . To disentangle the costs of harassment versus the costs of mating, we held females at a low or high density with males whose claspers were modified to prevent insemination, and compared these to females held with normal males and to those held with females or alone. A reduced longevity was observed when females were held under high density conditions with males or females, regardless if male claspers had been modified. There was no consistent effect of harassment on female fecundity. Net reproductive rate (R) was higher in females held at low density with normal males compared to females held with males in the other treatments, even though only a small number of females showed direct evidence of remating. Indirect costs and benefits that were not due to harassment alone were observed. Daughters of females held with normal males at high density had reduced longevity compared to daughters from females held without conspecifics. However, their fitness (R) was higher compared to females in all other treatments. Overall, our results indicate that females do not suffer a fitness cost from harassment of males when kept at moderate densities, and they suggest the potential for benefits obtained from ejaculate components.
对昆虫的性骚扰研究表明,雌性可能会因雄性的骚扰和交配而付出多种代价。在此,我们研究了在主要为单配偶制的蚊子中,雄性骚扰对雌性适合度各组成部分的直接和间接代价。为了区分骚扰代价与交配代价,我们将雌性与抱握器经过改造以防止授精的雄性以低密度或高密度饲养在一起,并将其与与正常雄性饲养在一起的雌性以及与雌性或单独饲养的雌性进行比较。当雌性与雄性或雌性在高密度条件下饲养时,无论雄性抱握器是否经过改造,其寿命都会缩短。骚扰对雌性繁殖力没有一致的影响。与在其他处理中与雄性饲养在一起的雌性相比,与正常雄性在低密度下饲养的雌性净繁殖率(R)更高,尽管只有少数雌性有直接再次交配的证据。我们观察到了并非仅由骚扰导致的间接代价和益处。与未与同种个体饲养的雌性所产的女儿相比,与正常雄性在高密度下饲养的雌性所产的女儿寿命缩短。然而,与所有其他处理中的雌性相比,它们的适合度(R)更高。总体而言,我们的结果表明,当以中等密度饲养时,雌性不会因雄性的骚扰而遭受适合度代价,并且它们表明从射精成分中获得益处的可能性。