灭绝风险很大程度上取决于有助于随机性的因素
Brett A Melbourne1, Alan Hastings
1Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado 80309, USA. brett.melbourne@colorado.edu
Nature
|July 4, 2008
概括
了解灭绝风险需要考虑人口随机性和环境随机性. 新的模型揭示了人口因素,而不是环境因素,往往导致灭绝风险,可能导致当前保护工作的低估.
科学领域:
- 生态生态学 生态生态学
- 人口动态 人口动态
- 保护生物学 保护生物学
背景情况:
- 自然种群的灭绝风险受到随机因素的影响.
- 随机性包括人口随机性,环境随机性和人口异质性.
- 以前的模型往往未能将所有类型的随机性整合到全面的风险评估中.
研究的目的:
- 开发和分析机械的随机里克尔模型,包括人口随机性,环境随机性和人口异质性.
- 调查这些随机因素对人口灭绝风险的综合影响.
- 为了比较一个完整的随机模型与更简单的传统模型的预测能力.
主要方法:
- 一个随机Ricker模型家族的推导,具有随机因素的不同组合.
- 将完整的随机模型应用于Tribolium castaneum的实验室种群.
- 对模型输出进行比较分析,以确定不同随机性源的相对重要性.
主要成果:
- 灭绝风险高度依赖于模型中包含的随机因素的特定组合.
- 完整的随机模型是必要的,以准确确定环境与人口变化的相对重要性.
- 在Tribolium castaneum中,人口随机性是变化的主要驱动因素,与较简单模型的结论相反.
结论:
- 目前对灭绝风险的估计可能被严重低估,原因是错误地将变异性归因于环境因素而不是人口因素.
- 与环境来源相比,随机性的人口来源对等变化水平的灭绝风险更高.
- 准确的灭绝风险评估需要使用包括所有相关的人口和环境因素在内的综合性随机模型.
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