|| 要旨トップ | 目次 |||日本生態学会第68回全国大会 (2021年3月、岡山) 講演要旨
一般講演（口頭発表） H01-02 （Oral presentation）
Social living provides multiple benefits, but it also carries costs such as inter- and intra-sexual conflicts. How communal animals manage sexual conflicts is poorly understood. Here, we show how gregarized desert locusts manage such conflicts through lekking behaviors (i.e., male aggregation). Our laboratory experiments demonstrated that single females (i.e., females that were not mate-guarded by a male) could not physically prevent mating attempts by males. However, in the field, we found that egg-developing, gregarized females occupied separate sites far from males and were single, whereas males aggregated on open ground, waiting for gravid females to enter the lekking sites. Once a male mounted a given female, no other males attacked the pair; therefore, mating pairs were protected during the vulnerable time of oviposition. In comparison, solitary locusts displayed balanced sex ratio in low density populations, and females mated irrespective of their ovarian state. Our results indicate that the mating behaviors of desert locusts are density dependent and that gregarious behavioral group separation may minimize the costs of inter- and intra-sexual conflicts, ultimately facilitating the reproductive success of the population.