Saether S A, Fiske P, Kålås J A
Department of Zoology, Norwegian University of Science and Technology, N-7491 Trondheim, Norway.
Proc Biol Sci. 2001 Oct 22;268(1481):2097-102. doi: 10.1098/rspb.2001.1745.
The males of lekking species are not expected to be choosy about mating because a reduced reproductive rate due to lost mating opportunities should outweigh any benefits of male choice. Females have traditionally not been expected to be competitive in this system since their reproduction has usually been assumed to be unconstrained by male availability. Here we show that, in contrast to these predictions, males are choosy and females may be competitive in the lekking great snipe Gallinago media. Males preferred by many females often refused to copulate with and even chased away females that the male had already copulated with, whereas females seemed to compete for repeated copulations. We conclude that choosiness may sometimes pay for popular males in those lekking species where females copulate repeatedly. Apparently, evolutionary conflicts of interest between individuals may cause a richer repertoire of behavioural adaptations than, to our knowledge, hitherto realized.
传统观点认为，在求偶场物种中，雄性对交配对象不会挑剔，因为因失去交配机会而降低的繁殖率所带来的负面影响，应会超过雄性选择的任何益处。在这个体系中，传统上也认为雌性不会具有竞争性，因为通常假定它们的繁殖不受雄性可获得性的限制。然而，我们在此表明，与这些预测相反，在大沙锥（Gallinago media）这种求偶场物种中，雄性会挑剔，而雌性可能具有竞争性。受许多雌性青睐的雄性常常拒绝与已经与之交配过的雌性交配，甚至会将其赶走，而雌性似乎会为了多次交配而竞争。我们得出结论，在雌性会多次交配的求偶场物种中，对于受欢迎的雄性而言，挑剔有时可能是有利的。显然，个体之间的利益进化冲突可能会导致行为适应方式比我们所知的迄今为止所认识到的更加丰富多样。
