de Mazancourt C, Johnson E, Barraclough T G
Redpath Museum, McGill University, 859 Sherbrooke St. W, Montreal, QC, Canada H3A 2K6.
Ecol Lett. 2008 Apr;11(4):380-8. doi: 10.1111/j.1461-0248.2008.01152.x. Epub 2008 Jan 31.
Despite growing interplay between ecological and evolutionary studies, the question of how biodiversity influences evolutionary dynamics within species remains understudied. Here, using a classical model of phenotypic evolution in species occupying a patchy environment, but introducing global change affecting patch conditions, we show that biodiversity can inhibit species' evolution during global change. The presence of several species increases the chance that one or more species are pre-adapted to new conditions, which restricts the ecological opportunity for evolutionary responses in all the species. Consequently, environmental change tends to select for changes in species abundances rather than for changing phenotypes within each species. The buffering effects of species diversity that we describe might be one important but neglected explanation for widely observed niche conservatism in natural systems. Furthermore, the results show that attempts to understand biotic responses to environmental change need to consider both ecological and evolutionary processes in a realistically diverse setting.
尽管生态研究与进化研究之间的相互作用日益增强，但生物多样性如何影响物种内部进化动态这一问题仍未得到充分研究。在此，我们使用一个适用于占据斑块状环境物种的经典表型进化模型，但引入影响斑块条件的全球变化因素，结果表明生物多样性在全球变化过程中会抑制物种进化。多个物种的存在增加了一个或多个物种预先适应新环境条件的可能性，这限制了所有物种进行进化响应的生态机会。因此，环境变化往往会促使物种丰度发生改变，而非每个物种的表型发生变化。我们所描述的物种多样性的缓冲效应，可能是自然系统中广泛观察到的生态位保守性的一个重要但被忽视的解释。此外，研究结果表明，在现实多样的环境中理解生物对环境变化的响应时，需要同时考虑生态和进化过程。
