Moreover, after 1 year, the darker pigeons in the group (as measured by the percentage of wing surface covered by dark feathers) had higher concentrations of zinc in their feathers than lighter pigeons did, the researchers report online today in Biology Letters. (sciencemag.org)
On the downstroke, a large wing surface area is required to generate lift and propulsion. (newscientist.com)
They discovered leading - edge serrations can passively control the transition between laminar, or streamline air flow, and turbulent air flow over the upper wing surface, at angles of attack (AoA) between zero and 20 degrees. (sciencedaily.com)