Plant and animal populations can adapt to prolonged environmental changes if they have sufficient genetic variation in important phenological traits. The genetic regulation of annual cycles can be studied either via candidate genes or through the decomposition of phenotypic variance by quantitative genetics. Here, we combined both approaches to study the timing of migration in a long-distance migrant, the collared flycatcher (Ficedula albicollis). We found that none of the four studied candidate genes (CLOCK, NPAS2, ADCYAP1 and CREB1) had any consistent effect on the timing of six annual cycle stages of geolocator-tracked individuals. This negative result was confirmed by direct observations of males arriving in spring to the breeding site over four consecutive years. Although male spring arrival date was significantly repeatable (R = 0.24 ± 0.08 SE), most was attributable to permanent environmental effects, while the additive genetic variance and heritability were very low (h² = 0.03 ± 0.17 SE). This low value constrains species evolutionary adaptation, and our study adds to warnings that such populations may be threatened, e.g. by ongoing climate change.

如果动植物种群在重要的物候特征上具有足够的遗传变异，则它们可以适应长期的环境变化。可以通过候选基因或通过定量遗传方法分解表型方差来研究年度周期的遗传调控。在这里，我们结合了两种方法来研究长距离迁徙的捕蝇器（Ficedula albicollis）的迁徙时间。我们发现四个候选基因（CLOCK，NPAS2，ADCYAP1和CREB1）均未发现）对地理定位器跟踪的个人的六个年度周期阶段的时间安排有任何一致的影响。通过连续四年对春季到达繁殖场的雄性的直接观察，证实了这种阴性结果。尽管雄性春季到来日期可重复性 很高（R = 0.24±0.08 SE），但大多数归因于永久性的环境影响，而加性遗传方差和遗传力却很低（h ²  = 0.03±0.17 SE）。这个低值限制了物种进化的适应性，我们的研究增加了警告，即这种种群可能受到威胁，例如受到持续不断的气候变化的威胁。