演化速率假说的实验验证研究进展

doi:10.17520/biods.2025019

摘要/Abstract

摘要：

生物多样性的地理格局及其成因备受生态学家关注。演化速率假说(evolutionary speed hypothesis)是生物多样性纬度格局的主要解释之一。该假说认为低纬度地区物种形成速率更快, 并且温度是决定演化速率的主要环境因素。具体机制包括: (1)热带地区的高温能够缩短生物世代时间而增加物种的有效演化时间(单位时间内的有效世代数); (2)高温可以提高突变速率, 进而增加遗传变异——自然选择的原材料; (3)高温能够加速自然选择过程。尽管人们广泛地使用这一假说讨论野外观测数据, 严格的实验检验工作却很少。近期研究基于实验演化途径, 在精准控制环境温度的情形下, 对演化速率假说的具体机制进行了检验。本文对相关研究进行了全面总结, 对温度影响突变速率、选择和适应分化的实验演化研究进展进行了详细阐述, 并提出这些结论的普适性仍需要在更复杂的系统中进行验证。本文旨在为理解演化速率假说和生物多样性地理格局的形成机制提供帮助, 为预测气候变暖背景下的物种保护和疾病防控工作提供参考。

关键词: 生物多样性纬度梯度, 微生物实验演化, 适应性分化, 突变速率, 选择, 生态代谢理论

Abstract

Background: Ecologists have long been interested in the geographical distribution patterns of biodiversity and the underlying mechanisms. The evolutionary speed hypothesis (ESH) is one of the mainstream explanations for the latitudinal biodiversity gradient pattern. This hypothesis suggests that the higher temperatures in low-latitude regions accelerate speciation rates and thus increase the species richness through three mechanisms. Specifically, (1) high temperatures shorten generation times, thereby increase the effective evolutionary time (the number of effective generations per unit of absolute time); (2) high temperatures increase mutation rates and thus genetic variations—the raw material for natural selection; (3) high temperatures accelerate the process of natural selection. Though this hypothesis is widely debated based on observed data from nature, rigorous tests are rare.

Progress:The experimental evolution approach has been recently adopted to test specific mechanisms for ESH; and those studies were performed under well-controlled environmental temperatures. This article presents a comprehensive review of these studies about the consequences of temperature for mutation rates, selection and adaptive diversification. The generality of conclusions from those studies needs to be tested in more complex systems.

Prospects: The experimental evolution approach will further deepen our understanding of the evolutionary speed hypothesis and the mechanisms underlying the geographical patterns of biodiversity, and give insights for species conservation and disease control under climate warming.

Key words: latitudinal biodiversity gradient, microbial experimental evolution, adaptive radiation, mutation rates, selection, metabolic theory of ecology

褚晓琳, 张全国 (2025) 演化速率假说的实验验证研究进展. 生物多样性, 33, 25019. DOI: 10.17520/biods.2025019.

Chu Xiaolin, Zhang Quanguo (2025) A review of experimental evidence for the evolutionary speed hypothesis. Biodiversity Science, 33, 25019. DOI: 10.17520/biods.2025019.

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链接本文: https://www.biodiversity-science.net/CN/10.17520/biods.2025019

https://www.biodiversity-science.net/CN/Y2025/V33/I4/25019

图/表 3

图1 温度影响演化速率的生理学机制和生态学机制

Fig. 1 The physiological and ecological mechanisms underlying temperature consequences for evolutionary speed

图2 突变累积实验示意图

Fig. 2 A graphical illustration of mutation accumulation experiment

图3 高温增强选择作用示意图(改自Chu等(2020))。虚线代表祖先型菌株的适合度所在位置; 红线代表高温下的有利突变的适合度频率分布; 蓝线代表低温下的有利突变适合度频率分布。(a)高温通过增加有利突变的数量增强选择作用, (b)高温通过提高有利突变适合度后果增强选择作用。

Fig. 3 A diagram of the enhancement of selection by high temperature (Adapted by Chu et al (2020)). The vertical dashed line in each panel indicates the fitness of the wild type; red and blue lines represent the frequency distribution of fitness effects of beneficial mutations at high and low temperature, respectively. (a) High temperature increases the strength of selection by increasing the amount of beneficial mutations. (b) High temperature increases the strength of selection by enhancing the fitness effects of beneficial mutations.

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