Feather development grows, its spathe, which is where the rachis and vanes attach, continues to form. When spathe is finished developing, the calamus begins to form within the base of the spathe. The calamus is the quill of the feather, which is the bottom portion that stays mainly within the pulp cavity. From there, the feather is fully developed and will remain as such until molting occurs, causing it to fall off. Feathers fall off during molting, which occurs in the at different times through the year depending on the type of bird. Birds can molt for seasonal, reproductive and many other
A Donkey, 3 Rocks, and a Bird. A Donkey, 3 Rocks, and a Bird. A Donkey, 3 Rocks, and a Bird., also known as Donkey, Bird and Rocks and Donkey, Three Rocks, and a Bird, is an outdoor 1992 sculpture by Brad Rude, installed at Catlin Gabel School in West Haven-Sylvan, a census-designated place in Washington County and the Portland metropolitan area, in the U.S. state of Oregon. Brad Rude's "A Donkey, 3 Rocks, and a Bird." (1992), installed at Catlin Gabel School between the Lower School's science room and the Art Barn, is a cast bronze and stone sculpture depicting a life-size donkey and a bird