Morphology of isolation: Do continental and island forms vary within a cosmopolitan Odonate?

Few organisms known to science migrate as far and wide as the dragonfly known as the Wandering Glider, Pantala flavescens. Identifying morphological variation within a cosmopolitan species has the potential to provide insights into mechanisms driving dispersal and migration, as well as those influencing gene flow and isolation. Here, to measure proxies for dispersal ability, we measured and analyzed fore- and hind-wing features using automatic feature extraction. We used TOWD (Targeted Odonata Wing Digitization) feature extraction and landmarking wings for comparative shape analysis. Using gabor wavelet transformations and neural networks, we extracted wing vein patterns and other features such as wing length and area moments, thought to be correlated with flight behavior. With these data, we identified morphological patterns that varied between island and continental populations globally. For the first time, we analyze insular wing morphology for representatives from Australia, Hawai’i, French Polynesia, Line Islands, Micronesia, Borneo, Japan and the Philippine Islands, and compared to China, Thailand, Malaysia, Mexico, the United States, Mexico, Paraguay, and Ecuador. We uncover variation between continental and island groups and discuss its potential influence on the ecology and evolution of this species and other migrating animals.