了解实验进化模型的概括性的极限
Samantha E Forde1, Robert E Beardmore, Ivana Gudelj
1Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, California 95064, USA.
Nature
|September 12, 2008
概括
试验室模型和数学建模揭示了资源输入如何影响共同进化的多样性. 不同的宿主-寄生虫相互作用显示出不同的多样性模式,支持地理马赛克理论.
科学领域:
- 进化生物学是进化生物学.
- 生态理论 生态理论
- 微生物系统是微生物系统.
背景情况:
- 在现场测试进化和生态理论是具有挑战性的.
- 在体外模型系统为实验研究提供了替代方案.
- 评估体外发现的概括性至关重要.
研究的目的:
- 要确定实验结果是否特定于体外模型.
- 描述可能有不同行为的系统,并解释为什么.
- 研究现象型多样性与共同进化的系统中的资源投入之间的关系.
主要方法:
- 为T7-Escherichia coli共同进化的系统开发了一个数学模型.
- 与实验结果对模型进行验证.
- 调整模型以模拟其他共同发展的合作伙伴和相互作用.
主要成果:
- 同进化的种群始终表现出与资源输入的多样性差异,与非同进化的种群不同.
- 多样性变化的具体模式取决于感染性和相互作用类型的细节.
- 在T7-E. coli中的基因对基因相互作用导致高资源投入的低多样性.
- 匹配基因相互作用导致在高资源投入下最大的多样性.
结论:
- 在体外系统和数学模型的组合有效地隔离了系统特定的结果.
- 这种方法可以描述替代的生物系统,并解释潜在的机制.
- 这些发现支持了共同进化的地理马赛克理论,强调了进化结果的上下文依赖性.
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