Climatic conditions vary in spatial frequency globally. Spatially rare climatic conditions provide fewer suitable environments than common ones and should impose constraints on the types of species present locally and regionally. We used data on 467 North American angiosperms to test the effects of the spatial frequency of climatic conditions on ecological niche specialisation and functional diversity. We predicted that rare climates should favour generalist species that are able to inhabit a broader range of climatic conditions. Our results show that climate frequency filters species that differ in niche breadths and rare environments host species combinations with greater functional diversity. The proposed analytical approaches and hypotheses can be adapted to investigate different aspects of ecological assemblies and their biodiversity. We discuss different mechanisms regarding how spatial frequency of environments can affect niche composition and functional diversity. These should be useful while developing theoretical frameworks for generating a deeper understanding of its underpinnings.

中文翻译：

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气候条件的空间频率影响物种组成的生态位组成和功能多样性：被子植物。

气候条件总体上在空间频率上变化。空间稀少的气候条件提供的环境比普通气候条件少，应该限制本地和区域性物种的种类。我们使用了467个北美被子植物的数据来测试气候条件的空间频率对生态位专业化和功能多样性的影响。我们预测罕见的气候应该有利于能够栖息于更广泛气候条件下的通才物种。我们的结果表明，气候频率过滤器物种在利基宽度和稀有环境方面存在差异，其宿主组合具有更大的功能多样性。所提出的分析方法和假设可以适用于研究生态大会及其生物多样性的不同方面。我们讨论了有关环境空间频率如何影响生态位组成和功能多样性的不同机制。这些在开发理论框架以加深对其基础的理解时应该是有用的。