<Dl> <Dd> Pope's nose redirects here . It may also refer to the licence plate light on early Volkswagen Beetles . </Dd> </Dl> <Dd> Pope's nose redirects here . It may also refer to the licence plate light on early Volkswagen Beetles . </Dd> <P> Pygostyle describes a skeletal condition in which the final few caudal vertebrae are fused into a single ossification, 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 parson's nose, pope's nose, or sultan's nose . This is the fleshy protuberance visible at the posterior end of a bird (most commonly a chicken or turkey) that has been dressed for cooking . It has a swollen appearance because it also contains the uropygial gland that produces preen oil . </P> <P> Pygostyles probably began to evolve very early in the Cretaceous period, perhaps 140 - 130 million years ago . The earliest known species to have evolved a pygostyle were members of the Confuciusornithidae . The structure provided an evolutionary advantage, as a completely mobile tail as found in species such as Archaeopteryx is detrimental to its use for flight control . Modern birds still develop longer caudal vertebrae in their embryonic state, which later fuse to form a pygostyle . </P>

What is the parsons nose on a turkey