*Institute of Avian Research, Vogelwarte Helgoland, 26386 Wilhelmshaven, Germany; Max Planck Institute for Ornithology, Vogelwarte Radolfzell, 78315 Radolfzell, Germany; University of Zurich, Zoological Museum, Winterthurerstrasse 190, 8057 Zurich, Switzerland; Department of Zoology and Physical Anthropology, Faculty of Biology, Universidad Complutense de Madrid, 28040 Madrid, Spain.
Integr Comp Biol. 2009 Nov;49(5):493-506. doi: 10.1093/icb/icp029. Epub 2009 Jun 8.
Migration determines where, when, and in which order males and females converge for reproduction. Protandry, the earlier arrival of males relative to females at the site of reproduction, is a widespread phenomenon found in many migratory organisms. Detailed knowledge of the determinants of protandry is becoming increasingly important for predicting how migratory species and populations will respond to rapid phenological shifts caused by climatic change. Here, we review and discuss the potential mechanisms underlying protandrous migration in birds, focusing on evidence from passerine species. Latitudinal segregation during the non-breeding period and differences in the initiation of spring migration are probably the key determinants of protandrous arrival at the breeding sites, while sexual differences in speed of migration appear to play a minor role. Experimental evidence suggests that differences between the sexes in the onset of spring migratory activity are caused by differences in circannual rhythmicity or by photoperiodic responsiveness. Both of these mechanisms are hardwired and could prevent individuals from responding plastically to chronic changes in temperature at the breeding grounds. As a consequence, adaptive changes in both the timing of arrival in spring and of reproduction will require evolutionary (genetic) changes of the cue-response systems underlying the initiation and extent of migration in both males and females.
迁徙决定了雄性和雌性何时何地以及以何种顺序聚集进行繁殖。雄虫相对于雌虫更早到达繁殖地点的先熟现象是一种广泛存在于许多迁徙生物中的现象。详细了解先熟迁徙的决定因素对于预测迁徙物种和种群将如何应对气候变化引起的快速物候变化变得越来越重要。在这里，我们回顾和讨论了鸟类中先熟迁徙的潜在机制，重点关注雀形目物种的证据。非繁殖期的纬度隔离和春季迁徙开始的差异可能是雄虫先熟到达繁殖地的关键决定因素，而迁徙速度的性别差异似乎作用较小。实验证据表明，春季迁徙活动开始时雌雄之间的差异是由年节律或光周期反应的差异引起的。这两种机制都是固定的，可能会阻止个体对繁殖地温度的慢性变化做出灵活反应。因此，在春季到达时间和繁殖时间上的适应性变化都需要在雄性和雌性中引起迁徙起始和程度的 cue-response 系统的进化（遗传）变化。
