Local adaptation to climate has facilitated the global invasion of cheatgrass

Nature Communications
By: , and 

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Abstract

Local adaptation may facilitate range expansion during invasions, but the mechanisms promoting destructive invasions remain unclear. Cheatgrass (Bromus tectorum), native to Eurasia and Africa, has invaded globally, with particularly severe impacts in western North America. We aimed to identify mechanisms and consequences of local adaptation in the North American cheatgrass invasion. We sequenced 307 range-wide genotypes and conducted controlled experiments. We found that diverse lineages invaded North America, where long-distance gene flow is common. Nearly half of North American cheatgrass is comprised of a mosaic of ~19 locally adapted near clonal genotypes, each seemingly very successful in a different part of its range. Additionally, ancestry- and phenotype- environment clines in the native range predicted those in the invaded range, indicating pre-adapted genotypes colonized different regions. Common gardens showed directional selection on flowering time that reversed between warm and cold sites, potentially maintaining clines. In the Great Basin, genomic predictions of strong local adaptation identified sites where cheatgrass is most dominant. Our results indicate that multiple introductions and ongoing migration within the invaded range likely fueled pre-adaptation and subsequent dominance of cheatgrass in western North America. Understanding how environment and gene flow shape invasive adaptation is critical for managing ongoing invasions.

Suggested Citation

Gamba, D., Vahsen, M., Maxwell, T.M., Pirtel, N., Romero, S., Van Ee, J.J., Penn, A., Das, A., Ben-Zeev, R., Baughman, O.W., Blaney, C.S., Bodkins, R., Budha-Magar, S., Copeland, S.M., Davis-Foust, S.L., Diamond, A., Donnelly, R.C., Dunwiddle, P.W., Ensing, D.J., Everest, T.A., Hoitink, H., Holdrege, M.C., Hufbauer, R.A., Juzenas, S., Kalwij, J.M., Kashirina, E., Kim, S., Klisz, M., Klyueva, A., Langeveld, M., Lutfy, S., Martin, D., Merkord, C.L., Morgan, J.P., Nagy, D.U., Ott, J.P., Puchalka, R., Pyle, L.A., Rasran, L., Rector, B.G., Rosche, C., Sadykova, M., Shriver, R.K., Stanislavschi, A., Starzomski, B.M., Stone, R.L., Turner, K.G., Urza, A.K., VanWallendael, A., Wegenschimmel, C., Zweck, J., Brown, C., Leger, E.A., Blumenthal, D.M., Germino, M., Porensky, L.M., Hooten, M., Adler, P., Lasky, J.R., 2025, Local adaptation to climate has facilitated the global invasion of cheatgrass: Nature Communications, v. 16, 10203, 17 p., https://doi.org/10.1038/s41467-025-64799-9.

Publication type Article
Publication Subtype Journal Article
Title Local adaptation to climate has facilitated the global invasion of cheatgrass
Series title Nature Communications
DOI 10.1038/s41467-025-64799-9
Volume 16
Publication Date November 20, 2025
Year Published 2025
Language English
Publisher Nature
Contributing office(s) Forest and Rangeland Ecosystem Science Center
Description 10203, 17 p.
Additional publication details