Evolving to invade: Using geometric morphometrics to assess wing shape variation in the Antarctic non-native fly Trichocera maculipennis

Globalization has increased human movement, transforming ecosystems and introducing non-native species that threaten biodiversity, particularly in Antarctica. Due to its harsh climatic conditions, Antarctica has largely remained protected from biological invasions. However, rising human activity and environmental changes are facilitating the introduction of non-native species. The risks posed by species like Trichocera maculipennis are significant, as they can adapt and survive in new environments. This highlights the importance of understanding the adaptive factors that contribute to their success in order to prevent future invasions and protect the continent's unique ecosystem. The aim of this study was to quantify the wing morphological variation of T. maculipennis individuals associated with different Antarctic bases, analyzing this variation within a spatial and temporal context using morphometric tools. Samples were collected during Antarctic summer campaigns (2017/18 to 2019/20 and 2022/23) at the following research stations on King George Island: Artigas (Uruguay), Bellingshausen (Russia), Profesor Julio Escudero (Chile), and King Sejong (Korea). Morphometric analyses revealed changes in wing shape among study sites, with King Sejong individuals showing the most significant differences. Additionally, a temporal shift in wing size was observed, with specimens from 2017/18 and 2018/19 having larger average wings compared to those from 2019/20 and 2021/22. These results emphasize the importance of understanding the factors contributing to the success of non-native species to prevent future invasions and protect the unique ecosystem of Antarctica.