Strategic mate‐guarding behaviour in ladybirds

Abstract

Mate‐guarding behaviour is regarded as a means of increasing paternity share by reducing sperm competition. It is known to be a plastic response which varies with operational sex ratios and competitor presence in the vicinity. In a recent study, prolonged mating duration in Menochilus sexmaculatus (Fabricius) (Coleoptera: Coccinellidae) has been found to incorporate mate‐guarding behaviour. The present investigation was conducted to assess its plasticity in the presence of competitors. The physical and chemical presence of competitors of both sexes at varying densities was provided to a pair of ladybirds, and their time to commence mating, latent period and mate‐guarding duration was observed. These were compared to a control treatment where other partners were absent. All treatments were conducted with sibling as well as non‐sibling competitors. It was our hypothesis that mate guarding would be increased in the presence of male competitors and would be reduced by female presence. The results revealed that while mate‐guarding duration was increased by the chemical presence of males it was decreased by their physical presence. The latter result was attributed to interference by other males who dislodge the mating male in order to access the female. Female chemical presence had no effect on mate guarding, while physical presence increased the duration of mate guarding. The reasons for the latter behaviour require further investigation. Responses were not significantly affected by the relationship between the focal pair and the competitor. The authenticity of the mate guarding in this ladybird is strongly affirmed by our results.

Operational sex ratio and paternal age sway mating and reproductive performance inMenochilus sexmaculatus(Coleoptera: Coccinellidae)

“…The decreased mating performance of old males has also been reported in other Coccinellidae species (Bista and Omkar 2015). The copulation duration, as shown in Figure 1B, was higher under extreme competition, which is probably a consequence of the increased possibility of sperm competition due to the male-biased sex ratio (Siva-Jothy 1987;Siva-Jothy and Tsubaki 1989;Parker 1993;Chaudhary et al 2017). This has also been previously observed in Rhagoletis juglandis (Cresson) (Diptera: Tephritidae) (Alonso-Pimentel and Papaj 1996) and M. sexmaculatus (Chaudhary et al 2017).…”

“…The presence of basic information about precopulatory (Dubey et al 2016a(Dubey et al , 2016b and postcopulatory mate choice behaviour (Chaudhary et al 2015) further provides a good foundation to build upon. The number of competitors (Chaudhary et al 2017) and age of mates (Omkar et al 2005) are known to affect the mating behaviour, reproductive performance (Mishra and Omkar 2004; Pervez et al 2004; Srivastava and Omkar 2004), and mate preference (Dubey et al 2016a(Dubey et al , 2016b. However, the effects of age in different sex ratio treatments need to be explored.…”

Me against who? Male guppies adjust mating behaviour according to their rival’s presence and attractiveness

“…These cues of competition risk have mostly been considered independently (e.g. Chaudhary, Mishra, & Omkar, ; Leonard & Hedrick, ; Plath & Bierbach, ; Tuni, Weber, Bilde, & Uhl, ). As such, their integrated impact on male mating behaviour adjustment remains poorly understood.…”

Male mate choice in the chameleon grasshopper (Kosciuscola tristis)

“…For example, in the long‐tailed dance fly ( Rhamphomyia longicauda ) males visually assess females prior to copulation and show a preference for larger females (Funk & Tallamy, ). Instead, males may try to outperform other males in courtship (e.g., bowerbirds, Borgia & Coleman, ), they may engage in costly physical fights against each other for specific females (e.g., bighorn sheep, Hogg, ; grasshoppers, Umbers, Tatarnic, Holwell, & Herberstein, ; Umbers, Tatarnic, Holwell, & Herberstein, ), or they may guard females that are about to become sexually receptive (e.g., crustaceans, Jormalainen, ; beetles, Chaudhary, Mishra, & Omkar, & Tregenza, T., ).…”