# Genomic Insights Into the Body Size Evolution in Mustelidae (Mammalia: Carnivora)

## TL;DR

This study explores how mustelid mammals evolved different body sizes by analyzing their genomes and identifying genes linked to body mass variation.

## Contribution

The study identifies 149 genes associated with body size variation and reveals convergent selection in metabolic and developmental pathways in mustelids.

## Key findings

- 149 genes were found to be significantly associated with body mass variation in mustelids.
- Genes related to growth signaling and energy metabolism are under convergent positive selection in large-bodied mustelid lineages.
- Phylogenetic comparative methods revealed 125 positively selected and 409 rapidly evolving genes in large-bodied mustelid species.

## Abstract

The extraordinary body size diversity within Mustelidae makes this carnivoran family an exceptional model for investigating adaptive evolution, yet the genomic underpinnings of their morphological variation have remained largely unexplored. Herein, we conducted a comprehensive comparative genomic analysis of 19 mustelid species to investigate the genetic foundations underlying the extraordinary range of body sizes within this family. We accounted for phylogenetic relatedness in our analyses to avoid statistical non‐independence due to shared ancestry and identified 149 genes significantly associated with body mass variation across the mustelid phylogeny (body size‐associated genes, BAGs) and, through selection pressure analyses, further detected 125 positively selected and 409 rapidly evolving genes in large‐bodied mustelid lineages. We found that body size evolution in mustelids is driven by convergent positive selection in metabolic, developmental, and cytoskeletal pathways, with genes involved in growth signaling and energy metabolism underlying the remarkable morphological diversity observed across the family. Our study reveals the genetic basis of body size evolution in mustelids, offering important insights into the core mechanisms driving adaptive phenotypic diversity among mammals.

The comparative genomic analysis of 19 mustelid species provides insights into the genetic basis of body size evolution, identifying candidate genes and pathways under selection that underlie the remarkable morphological diversity in Mustelidae.