The Galápagos Islands are home to a tremendous diversity of plants and animals found nowhere else in the world. But why this is, and when it all began, remains something of an open question. Now scientists may have at least one more piece of the puzzle. According to a new study out today in the journal Earth and Planetary Science Letters, the geologic formation of one particular part of the archipelago–the part responsible for the huge biodiversity–formed, approximately 1.6 million years ago.