遗传控制鸟类迁徙路径 By tracking hybrids between songbird species, investigators have found that migration routes are under genetic 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 routes: some used intermediate routes across less suitable areas, while others used the same routes as one parental 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 speciation, that differences in migratory behavior could be acting as postmating reproductive isolating barriers, said lead author Kira Delmore.
大学英语四级听力考试模拟试题(8)
英语四级听力精练短对话15
英语四级听力精练长对话5
英语四级考试听力备考笔记(10)
英语四级考试听力备考笔记(9)
英语四级听力精练短对话13
英语四级听力精练短对话22
英语四级听力精练短对话6
英语四级听力精练短对话1
英语四级听力精练短对话26
英语四级听力精练长对话8
英语四级考试听力备考笔记(16)
大学英语四级考试听力预测试题(19)
英语四级听力精练短对话28
英语四级考试听力备考笔记(27)
英语四级听力精练短对话19
英语四级听力精练长对话7
英语四级听力精练短对话8
英语四级听力精练短对话5
英语四级考试听力备考笔记(23)
英语四级听力精练短对话17
英语四级听力备考常考习语详解(8)
英语四级听力精练短对话11
英语四级听力精练长对话4
大学英语四级考试听力预测试题(15)
英语四级考试听力备考笔记(29)
英语四级听力精练长对话6
英语四级考试听力备考笔记(7)
英语四级听力精练短对话9
英语四级听力备考常考习语详解(7)
| 不限 |
| 英语教案 |
| 英语课件 |
| 英语试题 |
| 不限 |
| 不限 |
| 上册 |
| 下册 |
| 不限 |