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> They are about twice as efficient as airplanes by using flapping wings:-https://www.sciencedaily.com/releases/2016/07/160711120526.htm-"&apos;We&apos;ve known for quite a while that the aerodynamic theory for airplanes doesn&apos;t work so well in predicting the force of lift for flapping wings," says Leif Ristroph, an assistant professor at NYU&apos;s Courant Institute of Mathematical Sciences who directed the study. "We found that the drag or wind resistance also behaves very differently, and we put together a new law that could help explain how insects move through the air."-"&apos;To double its flight speed, an airplane must increase its thrust four-fold to counter the stronger wind resistance," Ristroph explains in outlining the law. "In contrast, we found that flapping wings have a drag that is in direct proportion to its flight speed -- to go twice as fast, an insect simply needs to double its thrust."-***-"The significance of aerodynamic drag and its strong increase with speed has been known since before the Wright brothers took flight. This fact is summarized by a mathematical law that posits wind resistance increases as the square of speed; hence, moving twice as fast requires four times the thrust to overcome the higher drag.-"Previous studies of flying insects, which beat their wings hundreds of times a second, suggested that these creatures do not obey this same relationship.-"To make this sense of this discrepancy, the researchers in Courant&apos;s Applied Math Lab built a robotic wing apparatus for measuring the motions, flows, and forces. The apparatus allowed the team to compare steady motions of a wing, as would occur for airplane flight, to the maneuvers of insects, in which their wings flap as they move through air.-"The team&apos;s results showed that the back-and-forth motions cause the drag to resist the movement in some instances; however, at other times the drag is actually directed forward, more like a thrust. The net force that results depends on the flight speed as well as the flapping motions, all of which the authors include in a new drag law."-Comment: It is always amazing how effectively developing evolutionary life produces results that we humans cannot mimic.