小翅稻蝗的精子竞争及交配行为的适应意义

许多昆虫有多次交配行为 ,因多次交配而引起不同雄虫的精子竞争 ,提供雌虫一种有效的性选择方式。小翅稻蝗 (Oxyayezoensis Shiraki)具多次交配行为 ,雌雄交配时间长 ,且交配后常伴有长时间的抱对行为。利用近缘种的种间交配 ,对小翅稻蝗的精子竞争、交配后抱对行为的适应意义进行了探讨。结果表明 ,小翅稻蝗的 P2 值 (最后交配雄虫子代的比例 )达 94 .3%±5 .3% ,说明最后交配雄虫的精子优先用于卵子的受精 ,交配时存在着精子置换。长时间的交配后抱对行为是为了阻止雌虫与不同雄虫个体的再交配 ,保护精子免被置换。

Sperm competition and adaptive significance of prolonged post-copulatory mounting in Oxya yezoensis (Orthoptera: Catantopidae)

Females copulate with multiple males in almost all insect species. This behavior allows different males to compete for fertilization and gives females the opportunity to mediate this competition. The eggs are typically fertilized by sperm from only one male, either the female's last mate or an earlier mate. The rice grasshopper, Oxya yezoensis Shiraki, shows not only multiple copulation, but also prolonged copulation and prolonged post-copulatory mounting between males and females. In this paper, sperm comp...