A river runs through it: Causal graphs capture riversʼ complex control on the genetic structure of populations

Clicks: 1
ID: 321012
2026
Article Quality & Performance Metrics
Overall Quality
Not rated
Combines reader engagement with the AI quality analysis. This article has not been analysed, so there is no overall score — reader engagement is measured and shown alongside.
AI Quality Assessment
Not analyzed
Readership in this journal

Ranked #14 of 54 articles by views in journal of heredity

Most read Least read

Bar heights use a square-root scale.

Mint this article as an NFT
Not yet minted

Create a permanent, verifiable on-chain record of this article on the Scimatic Network. The NFT is held in your Journament account, and you can withdraw it to your own wallet at any time.

5 SUSD one-off · no wallet required
Abstract
Abstract Earth’s physiographic features shape the genetic evolution of organisms, but understanding how such features act as barriers to gene flow requires quantifying characteristics of both the barrier and the organism. Many barrier characteristics, however, are interdependent and not fully captured by traditional multivariate statistics. Here, we evaluate the use of directed acyclic (causal) graphs and structural equation modeling (SEM) to test the Riverine Barrier Hypothesis using 27 river-spanning population genomic datasets of terrestrial plants and animals associated with 24 rivers across the contiguous United States. These data were paired with seasonality, river width, and river discharge data. SEM analysis revealed patterns not captured by standard approaches. River width had a strong effect on population differentiation, with distinct direct and indirect effects for high and low dispersers. Results suggest a negative width-Fst relationship for low dispersers, which we interpret to be due to topographic context of higher elevation or bedrock-incised rivers. In contrast, high dispersers had a positive relationship, indicating wider rivers present a greater barrier to dispersal. The total effect of river discharge was negligible because its direct effects on population differentiation were canceled out by indirect effects on other river features. Overall, the best-fitting SEM explained 52% of population differentiation for low dispersers and 13% for high dispersers, consistent with the idea that high-dispersing species are less impacted from river barrier effects. This proof of concept shows the utility of causal graphs and SEM at modeling complex relationships between Earth’s physiographic features and the organisms that evolve with them.
Reference Key
openalex_W7168300670 Use this key to autocite in the manuscript while using SciMatic Manuscript Manager or Thesis Manager
Authors Garett L Maag, Austin R Biddy, Maya F Stokes, Greer A Dolby
Journal journal of heredity
Year 2026
DOI
10.1093/jhered/esag056
URL
Keywords Keywords not found

Citations

No citations found. To add a citation, contact the admin at info@scimatic.org

No comments yet. Be the first to comment on this article.