Much still to be learned about Cahokia Mounds By ELIZABETH DONALD, AP COLLINSVILLE, Ill. (Map, News) - It's so much a part of the landscape that metro-east residents often don't even notice it, except when a visiting relative notices: "Look, there's the mound." Rising from what once was an endless grass sea parted by the Mississippi River, Monks Mound isn't even named after the Native American Indians who built it centuries ago, but the Trappist monks who lived there for only five years in the 19th century. No one knows what the long-vanished people who built the mounds called themselves,...