Why can tiny hummingbirds hover above a flower for an extended period? Douglas Warrick, a zoology professor at Oregon State University, utilized a specialized device to capture extremely brief moments in the wing movements of hummingbirds, approximately 250 microseconds (one microsecond is one-millionth of a second). This technology allowed him to analyze the airflow around the hummingbird’s wings and provide detailed insights into its flight phenomenon.
He discovered that hummingbirds generate 75% of their lift from the downstroke of their wings, while the remaining 25% comes from the upstroke. Generally, hummingbirds can be seen as a bridge between birds, which gain lift solely from the downstroke, and insects, which achieve lift through a combination of downstroke and upstroke. It is noteworthy that in other bird species, 100% of the lift is generated from the downstroke, whereas in insects, the distribution is typically 50-50.
Douglas Warrick believes that this experiment provides compelling evidence for the phenomenon of evolutionary convergence—organisms that are not closely related but evolve similar traits to exploit their environments effectively.
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