The lifestyle of Northwest Indians reflected the abundance of natural resources they found in the area. Transportation mostly consisted of canoes made from a tree trunk hollowed out by fire and tools. Transportation was not a key element of Northwest life, however, because the abundance of resources allowed people to settle permanently. Villages were often located at the mouths of streams for easy access to fishing grounds. Houses were made from wooden planks and decorated with elaborate carvings. They were inhabited by several families, which comprised an extended family. Each nuclear family was given its own cooking area, but households often cooperated by obtaining and preparing food. Food preparation was a time-consuming affair by today's standards. Fish — especially salmon — was the staple of the Northwest diet and there was a variety of ways to prepare it. Fish were frequently smoked or dried, pulverized and mixed with berries. Another method of preparation involved burying the fish in pits underground and allowing them to decay. It is now thought that this method must have introduced healthful microorganisms. Plant foods were wrapped in leaves or bark and cooked in an earthen oven, which consisted of a hole in the ground that was heated with hot stones. Clothing was most often fashioned from shredded cedar bark. In the summer, men wore breechcloths, if anything, and women wore plant fiber skirts. Furs and hides made warm cloaks for use in the winter months, while cone-shaped basket hats kept their wearers dry during rain. Both men and women practiced tattooing, and men often pierced their septums. Affluent families would flatten the heads of their infants' heads with a board, as a mark of beauty and nobility.