Pygostyle
Videos
Pygostyle is a skeletal condition in which the final few caudal vertebrae are fused into a single ossified structure, supporting the tail feathers and musculature. In modern birds, the rectrices attac
Confuciusornis sanctus with "rod"-type pygostyle and the two central tail feathers
Yixianornis grabaui, one of the oldest known species with a pygostyle like that in living birds
Flight feather
Videos
Flight feathers are the long, stiff, asymmetrically shaped, but symmetrically paired pennaceous feathers on the wings or tail of a bird; those on the wings are called remiges, singular remex, while th
Pygostyle
…in which the final few caudal vertebrae are fused into a single ossified structure, supporting the tail feathers and musculature. In modern birds, the rectrices attach to these. The pygostyle is the main component of the uropygium, a structure colloquially known as the bishop's nose, parson's nose, pope's nose…
Red kite (Milvus milvus) in flight, showing remiges and rectrices
Bald eagle (Haliaeetus leucocephalus) in flight with primaries spread to decrease drag and improve lift
Primary (left) and secondary (right) feathers of the common buzzard (Buteo buteo); note the asymmetrical orientation of the shafts
Secondaries of a pheasant showing eutaxis (above) and an eagle showing diastataxis (below)