 Despite this rebound, all surviving species are classified as "threatened" by the International Union for Conservation of Nature.The Galápagos Islands were discovered in 1535, but first appeared on the maps, of Gerardus Mercator and Abraham Ortelius, around 1570.The islands were named "Insulae de los Galopegos" (Islands of the Tortoises) in reference to the giant tortoises found there.