Population genetic structure of the globally introduced big‐headed ant in Taiwan

• Published in: Ecology and evolution 2022-12, Vol.12 (12), p.e9660-n/a
• Main Authors: Liu, Kuan‐Ling, Tseng, Shu‐Ping, Tatsuta, Haruki, Tsuji, Kazuki, Tay, Jia‐Wei, Singham, G. Veera, Yang, Chin‐Cheng Scotty, Neoh, Kok‐Boon
• Format: Article
• Language: English
• Subjects: bridgehead effect; Cytochrome; Cytochrome oxidase I; Cytochromes; Dispersal; Entomology; genetic bottleneck; Genetic diversity; Genetic structure; Genetics; Globalization; Haplotypes; International trade; Introduced species; invasion biology; invasive ant; Invasive insects; Invasive species; Mitochondria; Mitochondrial DNA; Mutation; Nonnative species; Phylogenetics; Population; Population genetics; population structure; Population studies; Populations
• ISSN: 2045-7758; 2045-7758
• DOI: 10.1002/ece3.9660

Global commerce and transportation facilitate the spread of invasive species. The African big‐headed ant, Pheidole megacephala (Fabricius), has achieved worldwide distribution through globalization. Since the late 19th century, Taiwan has served as a major seaport because of its strategic location. The population genetic structure of P. megacephala in Taiwan is likely to be shaped by international trade and migration between neighboring islands. In this study, we investigated the population genetics of P. megacephala colonies sampled from four geographical regions in Taiwan and elucidated the population genetic structures of P. megacephala sampled from Taiwan, Okinawa, and Hawaii. We observed a low genetic diversity of P. megacephala across regions in Taiwan. Moreover, we noted low regional genetic differentiation and did not observe isolation by distance, implying that long‐distance jump dispersal might have played a crucial role in the spread of P. megacephala. We sequenced the partial cytochrome oxidase I gene and observed three mitochondrial haplotypes (TW1–TW3). TW1 and TW3 most likely originated from populations within the species' known invasive range, suggesting that secondary introduction is the predominant mode of introduction for this invasive ant. TW2 represents a novel haplotype that was previously unreported in other regions. P. megacephala populations from Taiwan, Okinawa, and Hawaii exhibited remarkable genetic similarity, which may reflect their relative geographic proximity and the historical connectedness of the Asia‐Pacific region. Pheidole megacephala exhibits low genetic diversity across regions in Taiwan. Significant yet low regional genetic differentiation and the absence of isolation‐by‐distance implied that long‐distance jump dispersal may be relatively prevalent. Secondary introduction is the prevailing mode of introduction for P. megacephala and populations from Taiwan, Okinawa, and Hawaii exhibit remarkable genetic similarity.