进化生物学:动物的性别变化和相对身体大小
Peter M Buston1, Philip L Munday, Robert R Warner
1National Center for Ecological Analysis and Synthesis, University of California, Santa Barbara, California 93101, USA. buston@nceas.ucsb.edu
Nature
|April 13, 2004
概括
变性有机体表现出多样化的策略,自然选择倾向于优化生殖价值的最佳时间. 这项研究挑战了跨物种不变的性别变化时间的说法,质疑了普遍的自然选择原则.
科学领域:
- 进化生物学是进化的生物学.
- 生殖策略 生殖策略
- 性选择性选择性选择
背景情况:
- 生物体表现出不同的性别变化策略:女性优先,男性优先或重复性. 自然选择有利于改变性别,最大限度地提高个体的生殖价值.
- 奥尔索普和韦斯特提出,物种间的性别变化时间在最大体型的72%不变,这表明普遍的自然选择压力.
- 这项研究批判性地评估了Allsop和West关于性别变化时间的说法的经验支持和分析基础.
研究的目的:
- 批判性地评估所有动物中不变的性别变化时间的主张.
- 分析用于支持不变性变性假设的经验数据和统计方法.
- 提供基于现有数据和进化原理的反论点.
主要方法:
- 重新分析现有关于不同动物物种性别变化时间的经验数据.
- 关于性别变化发生在最大体型的固定百分比 (72%) 的说法的统计评估.
- 对性别决定机制和生命史策略的比较分析.
主要成果:
- 在最大体型的72%时,性别变化时间不变的说法并没有得到分析数据的强有力的支持.
- 经验数据显示,不同种类和环境背景的性别变化时间存在显著差异.
- 提出的普遍模式没有考虑到繁殖策略和进化压力的多样性.
结论:
- 性变化的时间并不是所有动物都不变的,正如所说的.
- 自然选择可能会驱动基于特定物种的生态和进化因素的各种性别变化策略.
- 关于所有动物发生性变化的基本相似自然选择过程的假设需要进一步的经验验验证.
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