A study examines ornamentation and climate adaptation in dragonflies. Organisms often adapt to changing climates. However, whether climatic adaptation includes the evolution of traits related to mating is unclear. Michael Moore and colleagues examined field guides and citizen-science observations of dragonflies, created a database of melanin wing ornaments and habitat climates for 319 dragonfly species, and evaluated the relationship between ornaments and temperatures. Although ornamental patches of melanin on dragonfly wings are advantageous in courtship and rival intimidation, they can increase body temperatures to more than 2 °C above ambient temperatures. Such a rise in body temperature benefits dragonflies in cool climates but may damage wing tissues, reduce fighting abilities, or prove lethal to dragonflies in warm climates. Male dragonflies in the coolest parts of North America have consequently evolved larger and darker melanin wing patches than male dragonflies in the warmest regions of the continent. During the warmest years between 2005 and 2019, the authors report, male dragonflies exhibited the smallest melanin wing patches. However, climate did not significantly affect wing ornaments of female dragonflies. Climate-warming projections suggested that male dragonflies will likely evolve even smaller melanin wing patches by 2070 as global warming increases. The findings suggest that mating-related traits of male, but not female, dragonflies consistently evolve to adapt to local climates, according to the authors.
Article #21-01458: "Sex-specific ornament evolution is a consistent feature of climatic adaptation across space and time in dragonflies," by Michael P. Moore et al.
MEDIA CONTACT: Michael P. Moore, Living Earth Collaborative, Washington University in St. Louis, MO; email: <email@example.com>
Proceedings of the National Academy of Sciences