ArticleNature communications2019
Birds repurpose the role of drag and lift to take off and land.
Article in Nature communications, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 11 papers.
What it found
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Who cites it
11 citing papers in PubMed, 56 citations in OpenAlex.
- The pectoralis muscle orientation as an indicator of the modes of wing-propelled locomotion in birds.Journal of anatomy · 2026Article
- Agile manoeuvrable flight via collaborative wing-tail adjustment of a flapping wing robot.Communications engineering · 2025Article
- Dynamically Controlled Flight Altitudes in Robo-Pigeons viaResearch (Washington, D.C.) · 2025Article
- Aerodynamic efficiency explains flapping strategies used by birds.Proceedings of the National Academy of Sciences of the United States of America · 2024Article
- Steady as they hover: kinematics of kestrel wing and tail morphing during hovering flights.The Journal of experimental biology · 2024Article
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- Article
- Identifying critical kinematic features of animate motion and contribution to animacy perception.iScience · 2023Article
- Birds both avoid and control collisions by harnessing visually guided force vectoring.Journal of the Royal Society, Interface · 2022Article
- How wingless salamanders fly.Nature · 2022Article
- Article
Corrections and comments
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Authors and funding
2 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The lift that animal wings generate to fly is typically considered a vertical force that supports weight, while drag is considered a horizontal force that opposes thrust. To determine how birds use lift and drag, here we report aerodynamic forces and kinematics of Pacific parrotlets (Forpus coelestis) during short, foraging flights. At takeoff they incline their wing stroke plane, which orients lift forward to accelerate and drag upward to support nearly half of their bodyweight. Upon landing, lift is oriented backward to contribute a quarter of the braking force, which reduces the aerodynamic power required to land. Wingbeat power requirements are dominated by downstrokes, while relatively inactive upstrokes cost almost no aerodynamic power. The parrotlets repurpose lift and drag during these flights with lift-to-drag ratios below two. Such low ratios are within range of proto-wings, showing how avian precursors may have relied on drag to take off with flapping wings.
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