性比以特定位置的方式影响对突变异位基因的性选择
Sakshi Sharda1, Brian Hollis2, Tadeusz J Kawecki1
1Department of Ecology and Evolution, University of Lausanne, Biophore, CH-1015 Lausanne, Switzerland and.
概括
较高的男性运行性比 (OSR) 可以加强果对有害基因的性选择. 然而,这种效应因基因和交配密度而异,显示OSR.
科学领域:
- 进化生物学是进化的生物学.
- 行为生态学 行为生态学
- 人口遗传学 人口遗传学
背景情况:
- 运行性比 (OSR) 理论上影响性选择强度.
- 很少有研究经验测试了OSR和性选择强度之间的直接关系.
- 有害的等位基因可能会受到性选择的影响,这会影响它们的频率.
研究的目的:
- 为了研究不同的男性:女性操作性比 (OSR) 如何影响Drosophila melanogaster*中两种不同的遗传变异的性选择.
- 确定交配池密度对不同OSR下的性选择强度的影响.
- 探索OSR对性选择的局部特异性影响.
主要方法:
- 在Drosophila melanogaster*中对OSR (1:2, 1:1, 2:1男性:女性) 和交配密度 (18,36,54个体) 的实验操纵.
- 对于携带天然的 * ebony * 突变体或与野生类型男性竞争的转基因 * GFP * 插入的男性的相对父权份额的估计.
- 在连续三天评估父亲身份,以考虑交配相互作用的变化.
主要成果:
- 对*树*突变的性选择随着OSR的增加而加强,并随着时间的推移而减少,密度效应最小.
- 对*GFP*转基因的性选择是密度依赖的:它在高密度的OSR中增加,但在低密度的1:1OSR中最强.
- OSR和性选择强度之间的关系并不总是单调的,并且在*树*和*GFP*位点之间有所不同.
结论:
- OSR可以显著影响对有害基因的性选择,但这种关系是复杂的,并不总是线性的.
- 交配密度在调节OSR对性选择的影响方面起着至关重要的作用.
- 局部特异的表型效应可能解释了 * 木 * 突变体和 * GFP * 转基因对OSR和密度的差异反应,突出了性选择的细微性质.
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