title: Local divergence of thermal reaction norms among amphibian populations is affected by pond temperature variation.
abstract: Although temperature variation is known to cause large-scale adaptive divergence, its potential role as a selective factor over microgeographic scales is less well-understood. Here, we investigated how variation in breeding pond temperature affects divergence in multiple physiological (thermal performance curve and critical thermal maximum [CTmax]) and life-history (thermal developmental reaction norms) traits in a network of Rana arvalis populations. The results supported adaptive responses to face two main constraints limiting the evolution of thermal adaptation. First, we found support for the faster-slower model, indicating an adaptive response to compensate for the thermodynamic constraint of low temperatures in colder environments. Second, we found evidence for the generalist-specialist trade-off with populations from colder and less thermally variable environments exhibiting a specialist phenotype performing at higher rates but over a narrower range of temperatures. By contrast, the local optimal temperature for locomotor performance and CTmax did not match either mean or maximum pond temperatures. These results highlight the complexity of the adaptive multiple-trait thermal responses in natural populations, and the role of local thermal variation as a selective force driving diversity in life-history and physiological traits in the presence of gene flow.
authors.affiliation: Animal Ecology/Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, SE-75236, Uppsala, Sweden. richterboixalex@gmail.com.
authors.forename: Alex
authors.initials: A
authors.lastname: Richter-Boix
authors.affiliation: Department of Evolutionary Ecology, Estación Biológica de Doñana, CSIC, Avda. Américo Vespucio s/n, 41092, Sevilla, Spain.
authors.forename: Marco
authors.initials: M
authors.lastname: Katzenberger
authors.affiliation: Department of Evolutionary Ecology, Estación Biológica de Doñana, CSIC, Avda. Américo Vespucio s/n, 41092, Sevilla, Spain.
authors.forename: Helder
authors.initials: H
authors.lastname: Duarte
authors.affiliation: Grupo de Investigación BIOCOST, University of Coruña, 15071, Coruña, Spain.|Current Address: Population Genetics, Institute of Marine Research, 5817, Bergen, Norway.
authors.forename: María
authors.initials: M
authors.lastname: Quintela
authors.affiliation: Department of Evolutionary Ecology, Estación Biológica de Doñana, CSIC, Avda. Américo Vespucio s/n, 41092, Sevilla, Spain.
authors.forename: Miguel
authors.initials: M
authors.lastname: Tejedo
authors.affiliation: Animal Ecology/Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, SE-75236, Uppsala, Sweden.
authors.forename: Anssi
authors.initials: A
authors.lastname: Laurila
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D017753:Ecosystem; D051456:Gene Flow; D007814:Larva / Q000254:growth & development / Q000502:physiology; D010641:Phenotype; D061005:Ponds; D011898:Ranidae / Q000254:growth & development / Q000502:physiology*; D013550:Swimming; D013696:Temperature
keywords: Amphibians; CTmax; FST-QST; countergradient variation; ectotherms; generalist-specialist trade-off; hotter-colder; thermal adaptation; thermal fluctuations; thermal performance curves