Original sentence: It is believed that Caral may answer questions about the origins of the Inca and the development of the first cities.They argue that the artifact is evidence that the quipu record keeping system, a method involving knots tied in rope that was brought to perfection by the Inca, was older than any archaeologist had previously guessed
Edited sentence: Since the site is a thousand years older than the earliest civilization in the Americas, it is believed that Caral may answer questions about the origins of the Inca and the development of the first cities.They argue that the artifact is evidence that the quipu writing system, a method involving knots tied in rope that was brought to perfection by the Inca, was older than any archaeologist had previously guessed