Department of Biology, University of North Carolina, Chapel Hill, North Carolina 27599, USA.
Am Nat. 2010 Aug;176(2):E50-65. doi: 10.1086/650723.
One of the primary ecological hypotheses put forward to explain patterns of biodiversity is known as the more-individuals hypothesis of species-energy theory. This hypothesis suggests that the number of species increases along the global energy gradient primarily as a result of an increase in the total number of individuals that can be supported along that gradient. Implicit in this hypothesis is that species richness should scale with energy in the same way in which it scales with area in species-area relationships. We developed a novel framework for thinking about the interaction of area and energy, and we provide the first global test of this equivalence assumption using a data set on terrestrial breeding birds. We found that (1) species-energy slopes are typically greater than species-area slopes, (2) the magnitude of species-area and species-energy slopes varies strongly across the globe, and (3) the degree to which area and energy interact to determine species richness depends on the way mean values of species occupancy change along the energy gradient. Our results indicate that the increase in richness along global productivity gradients cannot be explained by more individuals alone, and we discuss other mechanisms by which increased productivity might facilitate species coexistence.
其中一个用来解释生物多样性模式的主要生态学假设被称为物种能量理论的更多个体假说。该假说表明，物种数量沿着全球能量梯度增加，主要是由于在该梯度上可以支持的个体总数增加。该假说隐含的意思是，物种丰富度应该以与物种-面积关系中面积相同的方式与能量成比例。我们开发了一种新颖的思考面积和能量相互作用的框架，并使用关于陆地繁殖鸟类的数据首次对这种等效假设进行了全球测试。我们发现：(1)物种-能量斜率通常大于物种-面积斜率；(2)物种-面积和物种-能量斜率的幅度在全球范围内变化很大；(3)面积和能量相互作用以确定物种丰富度的程度取决于物种占有率均值沿能量梯度变化的方式。我们的结果表明，沿全球生产力梯度的丰富度增加不能仅用更多的个体来解释，我们还讨论了其他一些机制，这些机制可能会促进生产力增加时的物种共存。
