波动的选择在野外的生态社区中保持着独特的物种表型
James T Stroud1,2,3, Michael P Moore4, R Brian Langerhans5
1School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332.
概括
长期物种停滞并非由持续稳定选择驱动. 相反,在多个时期的波动性选择维持了物种差异,并阻止了进化变化.
科学领域:
- 进化生物学是进化的生物学.
- 生态生态学 生态生态学
- 类学 类学 类学 类学
背景情况:
- 种类经常表现出长期不变的表型特征,这种模式归因于稳定选择.
- 稳定选择,有利于中间表型,被假设为同时出现的物种创造不同的适应性峰值.
- 尽管它被引用,但对持续稳定选择驱动长期进化静止的直接证据很少.
研究的目的:
- 为了研究自然选择在维持表型静止在Anolis社区的作用.
- 测试假设持续稳定选择是长期进化静止的原因.
- 描述整个社区的健身景观,并确定维持物种差异的机制.
主要方法:
- 直接测量了四种Anolis物种在野生中的自然选择.
- 量化了健身面积,并在社区内确定了当地的健身优点和谷.
- 分析了对每个物种起作用的选择的时间动态.
主要成果:
- 确定了一个复杂的全社区健身表面,其中四种Anolis物种中的每一种都占据着独特的健身峰值.
- 观察到,物种差异是由适应性进化的障碍所维持的,包括物种之间的健身谷.
- 发现物种保持在各自的峰值不是通过连续稳定选择,而是通过许多独立的,波动的选择周期的组合.
结论:
- 在物种中长期的表型停滞可能是由于波动的选择而不是持续的稳定选择.
- 连续稳定选择的经典模型不足以解释物种差异和进化停滞的维持.
- 了解选择的动态性质对于解释宏观进化模式和物种多样性的持久性至关重要.
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