Albinism despite its lack of chlorophyll it may grow to substantial size as a parasite, usually on the base of the (normal) redwood tree from which it first grew. Only about sixty examples of albino redwoods are known. Additionally, an even smaller number of "chimeric" redwood trees have both normal and white needles. Albinism has frequently occurred in progeny of Black Tartarian, Bing and Hedelfingen varieties of sweet cherry. The Albino Squirrel Preservation Society was founded at the University of Texas at Austin in 2001. Members of the society at the University of North Texas petitioned for an election to name
History of manifolds and varieties History of manifolds and varieties The study of manifolds combines many important areas of mathematics: it generalizes concepts such as curves and surfaces as well as ideas from linear algebra and topology. Certain special classes of manifolds also have additional algebraic structure; they may behave like groups, for instance. In that case, they are called Lie Groups. Alternatively, they may be described by polynomial equations, in which case they are called algebraic varieties, and if they additionally carry a group structure, they are called algebraic groups. The term "manifold" comes from German "Mannigfaltigkeit," by Riemann. In English, "manifold" refers to