Marine life of the Canary Islands a total of 5 different species of marine turtle that are sighted periodically in the islands, the most common of these being the loggerhead turtle. The other four are the green, hawksbill, leatherback, and Kemp's ridley turtle. Currently, there are no signs that any of these species breed in the islands, and so those seen in the water are usually migrating. However, it is believed that some of these species may have bred in the islands in the past, and there are records of several sightings of leatherback turtle on beaches in Fuerteventura, adding credibility to the theory. By far
History of manifolds and varieties spaces with a differentiable or topological structure, while "variety" refers to spaces with an algebraic structure, as in algebraic varieties. In Romance languages, manifold is translated as "variety" – such spaces with a differentiable structure are literally translated as "analytic varieties", while spaces with an algebraic structure are called "algebraic varieties". Thus for example, the french word "" means topological manifold. In the same vein, the Japanese word "" (tayōtai) also encompasses both manifold and variety. ("" (tayō) means various.) Ancestral to the modern concept of a manifold were several important results of 18th and 19th century mathematics. The oldest