loading page

Selection despite low genetic diversity and high gene flow in a rapid island invasion of the bumblebee, Bombus terrestris
  • +1
  • Cecilia Kardum Hjort,
  • Josephine Paris,
  • Henrik G. Smith,
  • Rachael Dudaniec
Cecilia Kardum Hjort
Lund University

Corresponding Author:cecilia.hjort@biol.lu.se

Author Profile
Josephine Paris
Polytechnic University of Marche
Author Profile
Henrik G. Smith
Lund University
Author Profile
Rachael Dudaniec
Macquarie University
Author Profile

Abstract

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, the bumblebee Bombus terrestris (Hymenoptera: Apidae) has successfully spread across the island of Tasmania (Australia) in less than 30 years, becoming abundant and competitive with native pollinators. We use RADseq to investigate the neutral and adaptive genetic processes associated with environmental and morphological variation following the invasion of B. terrestris in Tasmania. Across 15 sites, we found high gene flow with low genetic diversity, significant isolation-by-distance, and spatial variation in effective migration rates. A longitudinal band of restricted migration was evident across the mid-central region of Tasmania, corresponding to sites with high elevation, pastural land, low wind speeds and low precipitation seasonality. Tajima’s D indicated a recent population expansion for central sites extending from the south to the north of the island. Significant 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.
20 Jul 2023Submitted to Molecular Ecology
22 Jul 2023Submission Checks Completed
22 Jul 2023Assigned to Editor
22 Jul 2023Review(s) Completed, Editorial Evaluation Pending
30 Jul 2023Reviewer(s) Assigned
07 Sep 2023Editorial Decision: Revise Minor
06 Oct 20231st Revision Received
21 Oct 2023Review(s) Completed, Editorial Evaluation Pending
23 Oct 2023Editorial Decision: Revise Minor
31 Oct 20232nd Revision Received
01 Nov 2023Submission Checks Completed
01 Nov 2023Assigned to Editor
01 Nov 2023Review(s) Completed, Editorial Evaluation Pending
06 Nov 2023Editorial Decision: Accept