RRC ID 64607
Author Bontrager M, Usui T, Lee-Yaw JA, Anstett DN, Branch HA, Hargreaves AL, Muir CD, Angert AL.
Title Adaptation across geographic ranges is consistent with strong selection in marginal climates and legacies of range expansion.
Journal Evolution
Abstract Every species experiences limits to its geographic distribution. Some evolutionary models predict that populations at range edges are less well-adapted to their local environments due to drift, expansion load, or swamping gene flow from the range interior. Alternatively, populations near range edges might be uniquely adapted to marginal environments. In this study, we use a database of transplant studies that quantify performance at broad geographic scales to test how local adaptation, site quality, and population quality change from spatial and climatic range centers towards edges. We find that populations from poleward edges perform relatively poorly, both on average across all sites (15% lower population quality) and when compared to other populations at home (31% relative fitness disadvantage), consistent with these populations harboring high genetic load. Populations from equatorial edges also perform poorly on average (18% lower population quality) but, in contrast, outperform foreign populations (16% relative fitness advantage), suggesting that populations from equatorial edges have strongly adapted to unique environments. Finally, we find that populations from sites that are thermally extreme relative to the species' niche demonstrate strong local adaptation, regardless of their geographic position. Our findings indicate that both nonadaptive processes and adaptive evolution contribute to variation in adaptation across species' ranges. This article is protected by copyright. All rights reserved.
Volume 75(6)
Pages 1316-1333
Published 2021-6-1
DOI 10.1111/evo.14231
PMID 33885152
MeSH Adaptation, Physiological / genetics* Climate Ecosystem Gene Flow* Genetic Load Genetics, Population Geography Models, Genetic* Selection, Genetic* Spatial Analysis
IF 3.698
GBIF Plant specimens deposited in Osaka Museum of Natural History, Japan Vascular Plant Specimens of Kochi Prefectural Makino Botanical Garden Vascular Plant Specimen database of Kanagawa Prefectural Museum of Natural History Gunma Museum of Natural History, Vascular Plant Specimen Vascular plant specimens of Sugadaira Research Station, Mountain Science Center, University of Tsukuba Occurrence data of woody plants in the Ginkakuzi-san National Forest Vascular plant specimens of Nagano Environmental Conservation Research Institute, Nagano Prefecture Plant Observation Records of Japan Plant Specimen Database of Tama Forest Science Garden, Forestry and Forest Products Research Institute, Japan Plant specimens of Otaru Museum Plant specimens of Komatsu City Museum Vascular plant specimens of Akita Prefectural Museum Herbarium, University Archives and Collections, Fukushima University, Japan (FKSE) Angiospermatatophytina Collection of Saitama Museum of Natural History AIS Wildtype Populations of Arabidopsis Plant specimens of Oiso Municipal Museum Vascular Plant Collection of Natural History Museum and Institute, Chiba Plant Specimens of Kurashiki Museum of Natural History Herbarium Specimens of Tokushima Prefectural Museum, Japan Vascular Plants Collection of Sagamihara City Museum Plant specimens in the Museum of Nature and Human Activities, Hyogo Prefecture, Japan