Environmental filters of freshwater fish community assembly along elevation and latitudinal gradients

Aim

The aim was to identify drivers of historical freshwater fish community assembly by testing for interactions between functional traits and two climatic gradients, namely elevation and latitude. Many studies conclude that environmental filtering is the dominant process of community-wide trait convergence at high elevations and high latitudes, but a full understanding of which specific filters cause trait convergence is lacking.

Location

Great Plains–Rocky Mountains, USA.

Time period

1960–2018.

Major taxa studied

Freshwater fish.

Methods

Using 2,539 stream fish community surveys documenting the native distributions of 51 species, we evaluated trait–environment relationships (trade-offs) and trait–dispersion relationships (standardized effect sizes from null models) along elevation and latitudinal gradients in four functional trait categories. We tested whether elevation and latitude exhibited similar trait–environment and trait–dispersion r...