The Ostrich (Struthio camelus) is a large African flightless bird.
Its wings are also large, with a wingspan of about two metres (6 feet and 7 inches).
Ostriches have many differences from flying birds.
Flying birds have external feathers with hooks that lock together. The Ostrich external feathers do not have tiny hooks that lock together. These hooklets are called barbules. They zip the vanes of individual feathers together to make the feather strong enough to hold the airfoil (the shape of the wing that makes it aerodynamic). Similar foils in water are called hydrofoils.
Flying birds have a keel (like a fin) that their muscles are attached to. The Ostrich has a flat sternum that does not have a keel.
And, of course, the Ostrich is larger than flying birds.
The Ostrich has 50-60 tail feathers. Their wings have 16 primary feathers, 4 alular feathers, and 20-23 secondary feathers.
Their wings are used to keep them warm, and cool. Their wings are also used to attract a partner, and to assist them to turn and zig-zag.
Photographer: Martina Nicolls
Martina Nicolls: SIMILAR BUT DIFFERENT IN THE ANIMAL KINGDOM