Cicadas may have evolved faster flight to avoid a new predator: early birds. The rapid evolution of cicadas’ flight ability may have been spurred by the emergence of predatory birds, new research suggests. These insects’ bodies and wing shapes changed dramatically over the course of 160 million years, at the same time birds began to dominate the skies as aerial predators, according to the research, published in the journal Science Advances.
The study focused on giant cicadas in the Dunstaniidae and Palaeontinidae families during the Mesozoic era. It found that cicadas in the early Cretaceous may have become 39% faster and had 19% more flight muscle mass than their ancestors in the late Jurassic. This evolution was driven by predation pressure from birds, leading to an evolutionary “air race” that resulted in cicadas more closely resembling modern species.
Understanding the evolution of wings is challenging, as wings often do not fossilize well. Ancient giant cicadas provide a unique opportunity to study wing evolution due to their well-preserved fossils. The research team analyzed over 80 species of giant cicadas, mapping changes in wing shape and flight muscle mass over time. They found that longer, slimmer wings and increased flight muscle mass helped cicadas become faster and more efficient flyers.
The emergence of birds that could catch insects midflight around 150 million years ago likely drove the rapid evolution of cicadas’ flight abilities. The study suggests that cicadas evolved adaptations to outmaneuver their new predators, resulting in longer, slimmer forewings that increased flight speed.
While the research on increased flight speed is robust, there is some debate about whether cicadas also became more maneuverable. Fast-moving organisms often struggle to make sharp turns, leading to questions about the trade-offs involved in evolving faster flight. Despite these complexities, the study sheds light on the intricate relationship between predator-prey dynamics and evolutionary adaptation.
Overall, this research highlights the importance of studying ancient organisms to understand the processes that drive evolutionary change. By analyzing well-preserved fossils like giant cicadas, scientists can uncover the secrets of how species have adapted to changing environments and threats over millions of years.
Sierra Bouchér, a Washington, D.C.-based journalist with a background in science communication and animal behavior, notes the significance of this research in advancing our understanding of evolutionary biology. The study’s findings provide valuable insights into the impact of predators on prey species and the intricate mechanisms of adaptation that drive evolutionary change.