Mistaking geography for biology: inferring processes from species distributions

• Many commonly used methods infer ecological processes from species distributions.
• Historical biogeographic processes can cause spurious ecological inferences.
• Many empirical results in ecological biogeography may be driven by these biases.
• New methods may better handle these biases, but are comparatively rarely used.
• Future development in ecological biogeography requires better handling of spatial patterns.

Over the past few decades, there has been a rapid proliferation of statistical methods that infer evolutionary and ecological processes from data on species distributions. These methods have led to considerable new insights, but they often fail to account for the effects of historical biogeography on present-day species distributions. Because the geography of speciation can lead to patterns of spatial and temporal autocorrelation in the distributions of species within a clade, this can result in misleading inferences about the importance of deterministic processes in generating spatial patterns of biodiversity. In this opinion article, we discuss ways in which patterns of species distributions driven by historical biogeography are often interpreted as evidence of particular evolutionary or ecological processes. We focus on three areas that are especially prone to such misinterpretations: community phylogenetics, environmental niche modelling, and analyses of beta diversity (compositional turnover of biodiversity).