Wildlife of Pakistan bay with a mouth almost as wide as its length. Its freshwater source is the Dasht River, the largest seasonal river of Baluchistan. All three bays support mainly "A. marina" species of mangrove. Pakistan also plans to rehabilitate mangrove-degraded areas at Sonmiani and Jiwani in Balochistan. Along the shores of Astola and Ormara beaches of Balochistan and Hawk'e Bay and Sandspit beaches of Sindh are nesting sites for five endangered species of sea turtles: green sea, loggerhead, hawksbill, olive ridley and leatherback. Sea snakes such as yellow-bellied sea snake are also found in the pelagic zone of the sea. The
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