由DNA标记物揭示的多妻性红翼黑鸟的实现繁殖成功
Science (New York, N.Y.)
|December 7, 1990
概括
在红翼黑鸟中,多重父亲是常见的,原因是额外的对受精,通常来自邻居. 这种行为显著影响了男性的生殖成功,并挑战了关于鸟类多妻制的现有理论.
科学领域:
- * 行为生态学
- * 遗传学 遗传学 是一个
- * 进化生物学 进化生物学
背景情况:
- *多妻制是一种交配系统,雄性与多个雌性交配,在红翼黑鸟 (Agelaius phoeniceus) 中很常见.
- * 了解生殖成功的遗传基础对于进化研究至关重要.
- *以前的研究还没有完全量化替代性交配策略对多妻性物种繁殖成功的影响.
研究的目的:
- * 通过使用遗传标记来调查红翼黑鸟多重父亲的患病率.
- * 量化额外双胞胎受精对男性生殖成功的贡献.
- * 挑战和完善对鸟类多妻制演化的现有解释.
主要方法:
- *使用了超变性遗传标记物,包括由小鼠主要基因相容性复合体探针检测的新型位点特异性标记物.
- *分析了红翼黑鸟家族中的遗传亲属关系,以确定额外的后代.
- * 基于基因计算的个体雄性繁殖成功指标.
主要成果:
- *发现多个父亲是常见的,几乎一半的巢穴至少包含一个额外的双胞胎.
- * 额外对的受精通常是由邻近的雄性生育的.
- *雄性平均超过20%的繁殖成功来自额外的双胞胎受精,混了传统的措施.
结论:
- * 额外对交配是红翼黑鸟的一个重要的繁殖策略,影响了遗传多样性和雄性交配的成功.
- * 多重父亲的流行需要重新评估在多妻制系统中男性生殖成功的传统措施.
- *这些发现挑战了关于鸟类多妻制的进化驱动因素的既定假设.
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