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Measuring and Altering Mating Drive in Male Drosophila melanogaster
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自私的遗传元素在中促进多夫制
T A R Price1, D J Hodgson, Z Lewis
1School of Biosciences, University of Exeter, Cornwall Campus, Penryn TR10 9EZ, UK.
Science (New York, N.Y.)
|November 22, 2008
概括
雌性昆虫在面对携带有害基因的雄性时,重新结合以提高后代的生存率. 这项研究揭示,与低质量的雄性交配的风险推动了多夫制的演变,或多重交配行为.
科学领域:
- 进化生物学 进化生物学
- 行为生态学 行为生态学
- 遗传学 是一个遗传学.
背景情况:
- 尽管成本高昂,但雌性养 (多) 是常见的,这表明了诸如增加后代健身等益处.
- 对来自高健身男性的精子的受精偏见是多夫多妻制益处的一种拟议机制.
- 特定的遗传因素,如自私的遗传元素,在驱动多夫多妻制的作用尚未完全理解.
研究的目的:
- 为了研究导致女性胎率增加的进化压力.
- 测试假设,与携带有害基因的雄性交配的风险促进了多夫制的假设.
- 探索自私的遗传元素,精子竞争力和多重交配的进化之间的联系.
主要方法:
- 使用Drosophila pseudoobscura (果) 的实验进化.
- 暴露女性与携带特定性别比率扭曲基因的男性.
- 评估雌性转率和后代的健康状况,以应对有害基因的存在.
主要成果:
- 雌性Drosophila pseudoobscura在暴露于具有有害性性别比率扭曲基因的雄性时,进化出显著更高的转移率.
- 这种基因还降低了精子的竞争能力,表明遗传质量和受精成功之间存在联系.
- 观察到的再交配的增加表明,这是对与受损雄性交配的风险的直接反应.
结论:
- 与具有自私遗传元素的男性交配的风险会降低精子的竞争力,这可能会推动多夫制的演变.
- 自私的遗传因素,通常与男性遗传适应性降低有关,可能是促进雌性多重交配的常见因素.
- 这为动物王国中普遍存在的多夫制现象提供了新的解释.
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