Sandvik M, Rosenqvist G, Berglund A
Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18 D, SE-752 36 Uppsala, Sweden.
Proc Biol Sci. 2000 Nov 7;267(1458):2151-5. doi: 10.1098/rspb.2000.1262.
Where both sexes invest substantially in offspring, both females and males should discriminate between potential partners when choosing mates. The degree of choosiness should relate to the costs of choice and to the potential benefits to be gained. We measured offspring quality from experimentally staged matings with preferred and non-preferred partners in a sex-role-reversed pipefish, Syngnathus typhle L. Here, a substantial male investment in offspring results in a lower potential reproductive rate in males than in females, and access to males limits female reproductive success rather than vice versa. Thus, males are choosier than females and females compete more intensely over mates than do males. Broods from preferred matings were superior at escaping predation, when either males or females were allowed to choose a partner. However, only 'choosing' females benefited in terms of faster-growing offspring. Our results have important implications for mate-choice research: here we show that even the more competitive and less choosy sex may contribute significantly to sexual selection through mate choice.
当两性都在后代养育上投入大量精力时，雌性和雄性在选择配偶时都应该对潜在伴侣进行区分。挑剔程度应与选择成本以及可能获得的潜在收益相关。我们通过在性别角色颠倒的尖嘴鱼（Syngnathus typhle L.）中进行的实验性配对来衡量后代质量，这些配对分别是与偏好的和非偏好的伴侣进行的。在这种鱼中，雄性对后代的大量投入导致雄性的潜在繁殖率低于雌性，并且雌性获得雄性的机会限制了其繁殖成功率，而不是相反。因此，雄性比雌性更挑剔，并且雌性在争夺配偶方面比雄性竞争更激烈。当允许雄性或雌性选择伴侣时，偏好配对产生的幼体在躲避捕食方面表现更优。然而，只有“选择”伴侣的雌性在后代生长速度更快方面受益。我们的研究结果对配偶选择研究具有重要意义：我们在此表明，即使是更具竞争力且挑剔程度较低的性别，也可能通过配偶选择对性选择做出重大贡献。
