鸟类迁徙路径受遗传控制

By tracking hybrids ¹ between songbird（鸣禽） species, investigators ² have found that migration ³ routes are under genetic ⁴ control and could be preventing interbreeding. The research, which is published in Ecology Letters, was conducted using geolocators that, like GPS, record the position of a bird and allow its long distance movement to be tracked. Compared with their parents, hybrids exhibited increased variability in their migratory ⁵ routes: some used intermediate（中间的） routes across less suitable areas, while others used the same routes as one parental ⁶ group on fall migration and the other on spring migration., ,"This is the first time we've been able to track songbirds over the entire annual cycle, and the data we collected support a longstanding hypothesis in ecological ⁷ speciation, that differences in migratory behavior could be acting ⁸ as postmating reproductive isolating ⁹ barriers," said lead author Kira Delmore.