Methylation patterns at fledging predict delayed dispersal in a cooperatively breeding bird

PLoS One. 2021 Jun 4;16(6):e0252227. doi: 10.1371/journal.pone.0252227. eCollection 2021.


Individuals may delay dispersing from their natal habitat, even after maturation to adulthood. Such delays can have broad consequences from determining population structure to allowing an individual to gain indirect fitness by helping parents rear future offspring. Dispersal in species that use delayed dispersal is largely thought to be opportunistic; however, how individuals, particularly inexperienced juveniles, assess their environments to determine the appropriate time to disperse is unknown. One relatively unexplored possibility is that dispersal decisions are the result of epigenetic mechanisms interacting between a genome and environment during development to generate variable dispersive phenotypes. Here, we tested this using epiRADseq to compare genome-wide levels of DNA methylation of blood in cooperatively breeding chestnut-crowned babblers (Pomatostomus ruficeps). We measured dispersive and philopatric individuals at hatching, before fledging, and at 1 year (following when first year dispersal decisions would be made). We found that individuals that dispersed in their first year had a reduced proportion of methylated loci than philopatric individuals before fledging, but not at hatching or as adults. Further, individuals that dispersed in the first year had a greater number of loci change methylation state (i.e. gain or lose) between hatching and fledging. The existence and timing of these changes indicate some influence of development on epigenetic changes that may influence dispersal behavior. However, further work needs to be done to address exactly how developmental environments may be associated with dispersal decisions and which loci in particular are manipulated to generate such changes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animal Migration / physiology
  • Animals
  • Breeding / methods
  • DNA Methylation / genetics*
  • Ecosystem
  • Female
  • Male
  • Passeriformes / genetics*
  • Population Dynamics
  • Reproduction / genetics
  • Songbirds / genetics*

Grants and funding

This project was funded by the Natural Environment Research Council to AFR (NE/K005766), USD’s Arts and Sciences to ALL, the National Science Foundation (1504662) to AWS, and GSU-Armstrong’s Department of Biology and College of Science and Mathematics to AWS. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.