Data and code from: Geologic history explains freshwater fish species richness across the conterminous USA

Aim: Freshwater fishes comprise over 20% of vertebrate biodiversity despite occupying <1% of the Earth’s surface. However, species richness differs substantially among river basins. Fundamentally, richness patterns can be explained by spatial variation in diversification rates, evolutionary time, and habitat capacities, which are in turn shaped by landscape change over geologic timescales. To test how geologic disturbances have influenced the accumulation of freshwater fish biodiversity, we hypothesized species richness would be (1) ordered by regional geologic history, (2) associated with high or intermediate river capture rates, (3) higher in assemblages with older evolutionary origins, and (4) positively associated with stream size.
Time period: 2008-2019.
Location: Conterminous United States (USA).
Major Taxa: Freshwater fishes.
Methods: We analyzed native species richness from a spatially representative survey of 5,321 fish assemblages at 3,609 sites. Geologic history was determ..., , # Data and code from: Geologic history explains freshwater fish species richness across the conterminous USA

Dataset DOI: [10.5061/dryad.sqv9s4nh3](https://doi.org/10.5061/dryad.sqv9s4nh3)

## Description of the data and file structure

We compiled fish assemblage data from the National Rivers and Streams Assessment (NRSA) conducted by the US Environmental Protection Agency, spanning 5,321 sampling events at 3,609 unique sites. These data were joined with information on the native status of each fish species at each site, the evolutionary time of each species, and the geologic history of each site. The final dataset was analyzed using spatial linear models.

### Files and variables

#### File: Supplementary_File_1.html

**Description:** 

This Quarto document contains all the R code necessary to create, visualize, and analyze our dataset. The backbone of our dataset is fish assemblage data from the EPA National Rivers and Streams Assessment (NRSA), which is publicly available through t...,