Role of aridity in shaping adaptive genomic divergence and population connectivity in a southern African rodent
6 affiliations
- 1Institut des Sciences de l'Evolution de Montpellier ISEM, Univ Montpellier, CNRS, IRD, Montpellier, France
- 2IUF, Institut Universitaire de France, Paris, France
- 3Centre de Biologie pour la Gestion des Populations (CBGP), INRAE, IRD, Cirad, Institut Agro Montpellier, Univ Montpellier, Montpellier, France
- 4MGX, Univ Montpellier, CNRS, INSERM, Montpellier, France
- 5National Museum and Centre for Environmental Management, Department of Mammalogy, University of the Free State – Bloemfontein Campus, Bloemfontein, Free State, South Africa
- 6University of the Witwatersrand, Wits, School of Animal, Plant and Environmental Science, Gauteng, South Africa
Abstract
Elucidating the drivers of evolution in dry environments is central to understanding how organisms respond to climate change. While research on the genomics of adaptation is growing, aridity-driven intraspecific divergence remains poorly quantified. Here, we address this gap by using genomic data from 230 individuals of the arid-adapted four-striped mouse Rhabdomys bechuanae , sampled across an aridity gradient in southern Africa, a region facing increasing aridification. Combining these data with palaeoclimatic reconstructions and present-day aridity indices, we investigate, from a spatiotemporal perspective, how intraspecific genetic variation relates to aridity. Inference of past effective population size revealed a sharp decline in the late Pleistocene, coinciding with regional aridification and potentially reflecting changes in connectivity during dry periods. Current population structure followed a pattern of isolation by distance and mirrored the aridity gradient. Genotype-environment association analyses identified single nucleotide polymorphisms and genes significantly associated with aridity and genetically differentiated among populations, with functions related to water and energy conservation-as expected under arid conditions-as well as neurotransmission. These findings highlight the underappreciated role of neurological processes in coping with water and resource scarcity. More broadly, our integrative genomics approach suggests that aridity shapes population connectivity and adaptation, with implications for climate resilience.
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BibTeX
@article{keilani2026role,
title = {{Role of aridity in shaping adaptive genomic divergence and population connectivity in a southern African rodent}},
author = {Hamilcar Keilani and Anna-Sophie Fiston-Lavier and Pierre Caminade and Anne Loiseau and Maxime Galan and Hugues Parrinello and Carine Brouat and Raphaël Leblois and Nico Avenant and Neville Pillay and Guila Ganem and Carole M. Smadja},
journal = {Proceedings of the Royal Society B: Biological Sciences},
year = {2026},
month = oct,
doi = {10.1098/rspb.2026.1628},
url = {https://hal.umontpellier.fr/hal-05835253v1},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Role of aridity in shaping adaptive genomic divergence and population connectivity in a southern African rodent
AU - Hamilcar Keilani
AU - Anna-Sophie Fiston-Lavier
AU - Pierre Caminade
AU - Anne Loiseau
AU - Maxime Galan
AU - Hugues Parrinello
AU - Carine Brouat
AU - Raphaël Leblois
AU - Nico Avenant
AU - Neville Pillay
AU - Guila Ganem
AU - Carole M. Smadja
PY - 2026
DA - 2026/10/22
JO - Proceedings of the Royal Society B: Biological Sciences
DO - 10.1098/rspb.2026.1628
UR - https://hal.umontpellier.fr/hal-05835253v1
AB - Elucidating the drivers of evolution in dry environments is central to understanding how organisms respond to climate change. While research on the genomics of adaptation is growing, aridity-driven intraspecific divergence remains poorly quantified. Here, we address this gap by using genomic data from 230 individuals of the arid-adapted four-striped mouse Rhabdomys bechuanae , sampled across an aridity gradient in southern Africa, a region facing increasing aridification. Combining these data with palaeoclimatic reconstructions and present-day aridity indices, we investigate, from a spatiotemporal perspective, how intraspecific genetic variation relates to aridity. Inference of past effective population size revealed a sharp decline in the late Pleistocene, coinciding with regional aridification and potentially reflecting changes in connectivity during dry periods. Current population structure followed a pattern of isolation by distance and mirrored the aridity gradient. Genotype-environment association analyses identified single nucleotide polymorphisms and genes significantly associated with aridity and genetically differentiated among populations, with functions related to water and energy conservation-as expected under arid conditions-as well as neurotransmission. These findings highlight the underappreciated role of neurological processes in coping with water and resource scarcity. More broadly, our integrative genomics approach suggests that aridity shapes population connectivity and adaptation, with implications for climate resilience.
SN - 0962-8452
SN - 1471-2954
ER -