The head of the kestrel remains motionless in flight due to the bird's ability to hover by facing into the wind and matching its speed.


"The kestrel is a wild bird that is well-known in Europe, Asia and Africa. It has a special ability: it can maintain its head in a perfectly still position in the air by facing the wind. Though its body may sway in the wind, its head remains motionless, which increases the excellence of its vision in spite of all the motion." (Yahya 2002:56)

Design in Nature: How the Constructal Law Governs Evolution in Biology, Physics, Technology, and Social OrganizationsAugust 1, 2013
Adrian Bejan

Western OspreyFalcoSpecies