Thermotolerance adaptation to human-modified habitats occurs in the native range of the invasive ant Wasmannia auropunctata before long-distance dispersal

Julien Foucaud (1) , Olivier REY (2) , Stéphanie Robert (3) , Laurent Crespin (4, 5) , Jerome Orivel (6) , Benoit Facon (1) , Anne Loiseau (1) , Herve Jourdan (7) , Martin Kenne (8) , Paul Serge Mbenoun Masse (9) , Maurice Tindo (8) , Merav Vonshak (10, 1) , Arnaud Estoup

1 UMR CBGP - Centre de Biologie pour la Gestion des Populations
2 UMR CBGP - Centre de Biologie pour la Gestion des Populations
3 UMR BGPI - Biologie et Génétique des Interactions Plante-Parasite
4 UR EpiA - Unité de Recherche d'Épidémiologie Animale
5 LBBE - Laboratoire de Biométrie et Biologie Evolutive - UMR 5558
6 ECOFOG - Ecologie des forêts de Guyane
7 IMBE - Institut méditerranéen de biodiversité et d'écologie marine et continentale
8 Université de Douala
9 UY1 - Université de Yaoundé I
10 Stanford University

Key evolutionary events associated with invasion success are traditionally thought to occur in the introduced, rather than the native range of species. In the invasive ant Wasmannia auropunctata, however, a shift in reproductive system has been demonstrated within the native range, from the sexual non-dominant populations of natural habitats to the clonal dominant populations of human-modified habitats. Because abiotic conditions of human- modified habitats are hotter and dryer, we performed lab experiments on workers from a set of native and introduced populations, to investigate whether these ecological and genetic transitions were accompanied by a change in thermotolerance and whether such changes occurred before establishment in the introduced range. Thermotolerance levels were higher in native populations from human-modified habitats than in native populations from natural habitats, but were similar in native and introduced populations from human-modified habitats. Differences in thermotolerance could not be accounted for by differences in body size. A scenario based on local adaptation in the native range before introduction in remote areas represents the most parsimonious hypothesis to account for the observed phenotypic pattern. These findings highlight the importance of human land use in explaining major contemporary evolutionary changes.

Mots clés: adaptation; heat shock; invasive species; natural selection and contemporary evolution; thermotolerance; LINEAR MIXED MODELS; CRITICAL THERMAL LIMITS; FIRE ANT; BIOTIC HOMOGENIZATION; PHENOTYPIC PLASTICITY; PHYLOGENETIC TREES; INTRODUCED POPULATIONS; MULTIPLE INTRODUCTIONS; CLONAL REPRODUCTION; WORLDWIDE INVASION

Domaines: Sciences du Vivant [q-bio]

Julien Foucaud, Olivier REY, Stéphanie Robert, Laurent Crespin, Jerome Orivel, et al.. Thermotolerance adaptation to human-modified habitats occurs in the native range of the invasive ant Wasmannia auropunctata before long-distance dispersal. Evolutionary Applications, 2013, 6 (4), pp.721--34. ⟨10.1111/eva.12058⟩. ⟨hal-02281551⟩