 For efficient steady flight, the ratio of span to chord, the aspect ratio, should be as high as possible (the constraints are usually structural) because this lowers the lift-induced drag associated with the inevitable wingtip vortices.Long-ranging birds, like albatrosses, and most commercial aircraft maximize aspect ratio.Alternatively, animals and aircraft which depend on maneuverability (fighters, predators and the preyed upon, and those who live amongst trees and bushes, insect catchers, etc.)