在花杂交区的波动性选择
Diana Tataru1, Max De Leon1, Spencer Dutton1
1Department of Ecology and Evolutionary Biology, Tulane University, New Orleans, LA.
bioRxiv : the preprint server for biology
|July 1, 2024
概括
花物种之间的杂交可能会引入有益的干旱特征,但也会带来风险. 选择压力,而不是混合优势,维持这些混合区,影响基因流动.
科学领域:
- 进化生物学 进化生物学
- 生态生态学 生态生态学
- 遗传学 遗传学 是一个
背景情况:
- 在历史上,杂交被视为对进化有害.
- 最近的研究强调了杂交在适应和物种化中的作用.
- 环境变化对混合区维护的影响尚未完全理解.
研究的目的:
- 为了研究*Mimulus guttatus*和*Mimulus laciniatus*之间的适应性杂交.
- 确定空间和时间选择在维持自然杂交区中的作用.
- 评估父母物种和杂交物种在不同环境条件下的适应性.
主要方法:
- 父母和杂交花几代人的相互移植.
- 在加利福尼亚州塞拉内华达进行了两年多的实验,与相反的降雨 (干燥2021年,湿2023年) 相比.
- 在混合区和父区内进行详细的环境测量.
主要成果:
- 混合区在环境上与适应干旱的M. laciniatus息地相似.
- 杂交物种没有表现出一致的健身优势;选择主要是对父母物种起作用.
- *M. laciniatus*在息地中表现出比*M. guttatus*更高的适应性,在干旱年里选择偏好了类似M. laciniatus的特征.
- 后一代杂交动物在雨季出现遗传不相容的证据.
结论:
- 杂交可能有助于干旱适应性特征从 *M. laciniatus* 转移到 *M. guttatus*.
- 保持混合区的动力是积极和消极选择的平衡,而不仅仅是混合优势.
- 遗传不相容性和不同的选择压力相互作用,在*Mimulus*杂交区塑造基因流动模式.
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