Image via Wikipedia The pre-Columbian stone spheres found in the south Pacific region of Costa Rica have had all kinds of guesses made about their origin. They are so big and heavy, the heaviest 15 tons, that one of the guesses were that they were put there by aliens. Wrong! Archaeologist Ifigenia Quintanilla has put an end to speculation. The spheres were made by the indigenous people of the region.They were carved with hatchets, and they were a sign of power. Quintanilla says it is a way to make a statement. 15 tons says a lot.