The pygostyle is the main component of the uropygium, a structure colloquially known as the bishop's nose, 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 …

Pygostyle formation was analyzed across a variety of extant bird clades, and was found to occur as a progressive post-hatching event. Evidence for post-hatch pygostyle fusion was also found in Mesozoic specimens, presented in this study and elsewhere in the literature.

The pygostyle is a fused bony structure found at the posterior end of the vertebral column in birds, formed from the fusion of several caudal vertebrae. This structure supports the tail feathers and plays a crucial role in flight mechanics and balance.

The meaning of PYGOSTYLE is a plate of bone that forms the posterior end of the vertebral column in most birds and is formed by the union of vertebrae.

There is a short tail section, followed by a final fusion, termed the pygostyle (Figure 16-1). The pygostyle is an important structure that serves to mount the tail feathers, providing critical control surfaces, especially during takeoff and landing.

…of several fused vertebrae (pygostyle), as did the tails of all but the most primitive birds such as Archaeopteryx. Unlike modern birds, Ichthyornis possessed teeth, which are thought to have been used to hold its prey, manipulate objects, and preen its feathers.

The pygostylians fall into two distinct groups with regard to the pygostyle. The Ornithothoraces have a ploughshare -shaped pygostyle, while the more primitive members had longer, rod-shaped pygostyles.