Sexual conflicts, loss of flight, and fitness gains in locomotion of polymorphic water striders

摘要: In insect wing polymorphism, morphs with fully developed, intermediate, and without wings are recognized. The interpreted as a trade-off between flight flightlessness; the benefits of counterbalanced by costs development maintenance muscles. Such has been widely shown for reproductive developmental parameters, reduction is associated species stable habitats. However, in this context, role water locomotion performance not well explored. We chose seven striders (Heteroptera: Gerridae) model to study its relation sexual conflicts, namely, Aquarius elongatus (Uhler), paludum (Fabr.), Gerris insularis (Motschulsky), nepalensis Distant, latiabdominis Miyamoto, Metrocoris histrio (White), Rhagadotarsus kraepelini Breddin. estimated legs' stroke force, measured on tethered specimens placed force transducer attached their backs. By dividing body weight, we made comparisons. found positive relationship weight negative one force-to-weight ratio among species. was manifested differences terms force/weight ratio. bias toward winged or wing-reduced dependent, presumably related habitat preference. Water strider favouring permanent (G. nepalensis) showed higher apterous morph, but those temporary habitats (A. R. kraepelini) morphs' did differ significantly. Males had than females all three studied (namely, A. elongatus, G. nepalensis, kraepelini); these have type II mating strategy minimized struggle. hypothesized that I system, which males must struggle strongly subdue female, should outperform copulate successfully. This necessarily true mating.