在数字生物体中,来自资源竞争的自适应辐射
Stephanie S Chow1, Claus O Wilke, Charles Ofria
1Digital Life Laboratory 136-93, California Institute of Technology, Pasadena, CA 91125, USA.
Science (New York, N.Y.)
|July 3, 2004
概括
由于混合资源的频率依赖选择,物种丰富度在中间生产率达到顶峰,甚至在均的环境中也导致适应性辐射.
科学领域:
- 生态生态学 生态生态学
- 进化生物学 进化生物学
- 理论生物学 理论生物学
背景情况:
- 物种丰富性往往与生产率呈现出一个形的关系,在中间水平达到顶峰.
- 驱动这种模式的基本机制,特别是在资源驱动系统中,尚未完全理解.
- 环境异质性被认为是关键因素,但它的必要性仍在争论中.
研究的目的:
- 研究产生中间物种丰富性的机制.
- 确定环境异质性是否对于形的生产力-财富关系至关重要.
- 探索资源多样性和频率依赖选择在驱动适应性辐射中的作用.
主要方法:
- 在一个受控的,空间均的环境中,利用了正在发展的数字生物体的实验.
- 操纵资源的可用性和多样性,以模拟不同的生产力水平.
- 采用种群遗传学和生态建模来分析物种动态和进化轨迹.
主要成果:
- 在中间生产率水平上观察到最大的物种丰富度,与经验观察一致.
- 即使没有空间环境异质性,这种模式也出现了.
- 在一个多样化的限制资源池上进行频率依赖的选择被确定为主要驱动因素.
- 观察到适应性辐射,其特点是出现不同的表型和血统.
结论:
- 多样化的限制资源足以驱动适应性辐射并保持高物种丰富度.
- 取决于频率的选择,而不是环境异质性,可以解释物种丰富度在中间生产率的峰值.
- 这些发现提供了对资源驱动生态系统中生物多样性模式的机制性理解.
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