Flight-biomechanics researchers found, by capturing the breath of a hummingbird flying in a wind tunnel, that male hummingbirds expend negligibly more energy on flight when their tail feathers are extended to five times normal length.
Flight-biomechanics researchers found, by capturing the breath of a hummingbird flying in a wind tunnel, that male hummingbirds expend negligibly more energy on flight when their tail feathers are extended to five times normal length.