Fish out of water: Genomic insights into persistence of rainbowfish populations in the desert

Catherine R.M. Attard, Jonathan Sandoval-Castillo, Chris J. Brauer, Peter J. Unmack, David Schmarr, Louis Bernatchez, Luciano B. Beheregaray

Research output: Contribution to journalArticlepeer-review

3 Citations (Scopus)

Abstract

How populations of aquatic fauna persist in extreme desert environments is an enigma. Individuals often breed and disperse during favorable conditions. Theory predicts that adaptive capacity should be low in small populations, such as in desert fishes. We integrated satellite-derived surface water data and population genomic diversity from 20,294 single-nucleotide polymorphisms across 344 individuals to understand metapopulation persistence of the desert rainbowfish (Melanotaenia splendida tatei) in central Australia. Desert rainbowfish showed very small effective population sizes, especially at peripheral populations, and low connectivity between river catchments. Yet, there was no evidence of population-level inbreeding and a signal of possible adaptive divergence associated with aridity was detected. Candidate genes for local adaptation included functions related to environmental cues and stressful conditions. Eco-evolutionary modeling showed that positive selection in refugial subpopulations combined with connectivity during flood periods can enable retention of adaptive diversity. Our study suggests that adaptive variation can be maintained in small populations and integrate with neutral metapopulation processes to allow persistence in the desert.

Original languageEnglish
Pages (from-to)171-183
Number of pages13
JournalEvolution
Volume76
Issue number1
Early online date14 Nov 2021
DOIs
Publication statusPublished - Jan 2022

Keywords

  • Adaptive resilience
  • arid zone
  • climate change
  • freshwater fish
  • landscape genomics
  • metapopulation

Fingerprint

Dive into the research topics of 'Fish out of water: Genomic insights into persistence of rainbowfish populations in the desert'. Together they form a unique fingerprint.

Cite this