Selection despite low genetic diversity and high gene flow in a rapid island invasion of the bumblebee, Bombus terrestris.

Autor: Kardum Hjort C; Department of Biology, Lund University, Lund, Sweden.; School of Natural Sciences, Macquarie University, Sydney, New South Wales, Australia., Paris JR; Department of Life and Environmental Sciences, Marche Polytechnic University, Ancona, Italy., Smith HG; Department of Biology, Lund University, Lund, Sweden.; Centre for Environmental and Climate Science, Lund University, Lund, Sweden., Dudaniec RY; School of Natural Sciences, Macquarie University, Sydney, New South Wales, Australia.
Jazyk: angličtina
Zdroj: Molecular ecology [Mol Ecol] 2024 Jan; Vol. 33 (2), pp. e17212. Date of Electronic Publication: 2023 Nov 22.
DOI: 10.1111/mec.17212
Abstrakt: Invasive species are predicted to adjust their morphological, physiological and life-history traits to adapt to their non-native environments. Although a loss of genetic variation during invasion may restrict local adaptation, introduced species often thrive in novel environments. Despite being founded by just a few individuals, Bombus terrestris (Hymenoptera: Apidae) has in less than 30 years successfully spread across the island of Tasmania (Australia), becoming abundant and competitive with native pollinators. We use RADseq to investigate what neutral and adaptive genetic processes associated with environmental and morphological variation allow B. terrestris to thrive as an invasive species in Tasmania. Given the widespread abundance of B. terrestris, we expected little genetic structure across Tasmania and weak signatures of environmental and morphological selection. We found high gene flow with low genetic diversity, although with significant isolation-by-distance and spatial variation in effective migration rates. Restricted migration was evident across the mid-central region of Tasmania, corresponding to higher elevations, pastural land, low wind speeds and low precipitation seasonality. Tajima's D indicated a recent population expansion extending from the south to the north of the island. Selection signatures were found for loci in relation to precipitation, wind speed and wing loading. Candidate loci were annotated to genes with functions related to cuticle water retention and insect flight muscle stability. Understanding how a genetically impoverished invasive bumblebee has rapidly adapted to a novel island environment provides further understanding about the evolutionary processes that determine successful insect invasions, and the potential for invasive hymenopteran pollinators to spread globally.
(© 2023 The Authors. Molecular Ecology published by John Wiley & Sons Ltd.)
Databáze: MEDLINE
Externí odkaz: