''As land masses go, the Galápagos Islands are not very old. A little over four million years ago there was open ocean where they now lie, on the equator some 600 miles west of Ecuador. But submarine volcanic activity slowly built up the string of islands that Darwin visited in 1835. Indeed, it was Darwin who first recognized their volcanic origin, and who understood the profound implications of this origin for the history of life. For if the islands were volcanic, they must have formed after the creation of the world, and the organisms living there must have migrated there from someplace else. But since those organisms are found nowhere else, Darwin finally had to conclude that they had evolved there from South American ancestors.''
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But Darwin only had part of the answer. A more complete answer to the origin of the Galápagos could not be had until after 1958, when continental drift, or plate tectonics, was discovered. We now understand that the surface of the earth is divided into massive tectonic plates which slowly drift across the globe. The formation of the Galápagos is intimately tied to the history of the Nazca plate, on which they lie.
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