It is believed that, in ancient Korea, various types of divination were performed to help leaders decide about important state matters. Providing material evidence of such divination practices, oracle bones have been discovered at many shell midden sites along the southern coast of Korea. Most oracle bones were made from the scapula of deer, but some were also made from the bones of wild boars. It seems that the divination was performed by applying heat to a series of points on the bone, arranged like a grid. This practice appears to have been carried out before events of national importance, such as assembling a military force or heading out on a campaign, as well as to predict the agricultural harvest.