繁荣衰退的人口动态驱动着快速的遗传变化
Emily J Stringer1, Bernd Gruber1, Stephen D Sarre1
1Centre for Conservation Ecology and Genomics, Institute for Applied Ecology, University of Canberra, Canberra ACT 2617, Australia.
概括
澳大利亚干旱区的哺乳动物表现出对比的策略,维持遗传多样性,尽管环境波动. 一种物种通过稳定的种群来保护多样性,而另一种物种通过人口繁荣期间的快速遗传混合来恢复多样性.
科学领域:
- 生态生态学 生态生态学
- 进化生物学 进化生物学
- 遗传学 遗传学 是一个
背景情况:
- 环境变化和极端干扰威胁着物种,导致人口减少和遗传多样性丧失.
- 澳大利亚的干旱地区经历了严重的人口波动,但有些物种仍然存在并保持遗传多样性.
研究的目的:
- 在澳大利亚两个干旱区小哺乳动物中调查重复的人口波动的遗传后果.
- 了解如何在高度变化的环境中保持遗传多样性.
主要方法:
- 在13年内重复采集人口样本.
- 1903个个体的基因型测序.
- 对异卵性和人口差异化 (FST) 的分析.
主要成果:
- 沙内陆老鼠 (Pseudomys hermannsburgensis) 在人口爆发期间显示异构性降低和FST增加,在繁荣期间迅速恢复.
- 较小的毛脚 (Sminthopsis youngsoni) 保持了稳定的种群规模,并没有呈现异构性线性下降.
- 发现了两种对比的基因多样性维护机制.
结论:
- 变化的环境中的物种可以通过稳定的种群规模或在种群恢复期间的快速遗传混合来保持遗传多样性.
- 伪海 (Pseudomys hermannsburgensis) 通过快速的遗传混合来保护多样性,而Sminthopsis youngsoni则通过维持稳定的种群来做到这一点.
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