Populations grow and permanent settlements increase throughout the period, while regional adaptations to environmental conditions and the consequent specialized lifestyles evolve. In the Southwest, farming becomes more important and pithouses and storage structures are grouped into villages. The influential presence of Mexico to the south continues to be felt. In the Eastern Woodlands, mound groups that include residential areas are initiated in locations adjacent to major rivers, and the cultural pattern subsequently known as Mississippian begins. In the Arctic, whales are successfully hunted and the presence of a new archery/armor complex implies serious competition for available resources.