Beans (important source)

In the Iliad (8th century BCE) is a passing mention of beans and chickpeas cast on the threshing floor. Beans were an important source of protein throughout Old and New World history, and still are today. The oldest-known domesticated beans in the Americas were found in Guitarrero Cave, an archaeological site in Peru, and dated to around the second millennium BCE. However, genetic analyses of the common bean Phaseolus shows that it originated in Mesoamerica, and subsequently spread southward, along with maize and squash, traditional companion crops.