混乱通过放大当地人口噪音来减少物种灭绝
J C Allen1, W M Schaffer, D Rosko
1Department of Entomology and Nematology, University of Florida, Gainesville 32611-0740.
Nature
|July 15, 1993
概括
生态混乱,虽然可能导致本地灭绝,但可以通过减少多种群系统中的人口同步来防止广泛的物种灭绝. 这种复杂的动态可能会增强物种的生存.
科学领域:
- 生态生态学 生态生态学
- 理论生态学理论生态学
- 人口动态 人口动态
背景情况:
- 混沌在生态系统中的作用是有争议的,有些人认为它导致了灭绝,有些人认为它在模型中无处不在.
- 对生态混乱模型的现实主义和对经验证据的解释存在怀疑,随着随机模型经常被提出为替代品.
- 反对生态混乱的一个关键论点是,种群间的选择或增加的灭绝率消除了进化为混乱动态的物种,这是由混乱不可避免地导致极端人口波动和稀有性的信念驱动的.
研究的目的:
- 研究生态混乱对种群生存的影响,特别是在由多个相互作用种群组成的物种中.
- 挑战这样的假设,即混乱的动态必然会导致灭绝的可能性增加.
- 为了确定混乱的种群动态是否可以在某些条件下增强物种的持久性.
主要方法:
- 这项研究可能涉及到人口动态的数学建模,以模拟混乱的行为.
- 对模型输出的分析,以评估混乱动态,人口密度和灭绝风险之间的关系.
- 在混乱条件下的单个人口与多个人口 (超人口) 系统的灭绝概率的比较.
主要成果:
- 混乱的动态并不一定导致人口稀有.
- 虽然人口密度较低会增加本地灭绝风险,但混乱的振荡会使种群脱.
- 这种关系减少了种群波动的同步性,从而降低了所有种群同时灭绝的可能性.
结论:
- 生态混乱并不自动等同于所有物种的灭绝风险增加.
- 对于由多个相互联系的种群组成的物种,混乱的动态可以悖论地降低灭绝的总体概率.
- 超群体的空间结构和迁移模式在调解混乱对物种生存的影响方面发挥着至关重要的作用.
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