Traditionally swidden cultivators, the Mam favor dispersed settlements. Municipal cabeceras or "head towns" often consist of little more than a cluster of houses surrounding the church, town hall, and marketplace; the few streets usually radiate out from a central square in a grid pattern, an artifact of colonial town planning. All cabeceras now have electricity and potable water, but most lack urban amenities such as paved streets, shops, or diversions beyond the ubiquitous cantinas. Some 90 percent of Mam still live in scattered hamlets of less than 500 people. Although dispersed, hamlets maintain formal administrative ties to the cabecera of their municipio and share patterns of traditional dress and speech unique to the municipio as a whole. A high degree of endogamy also helps to maintain municipio cohesion. Mam houses typically consist of a hard-packed dirt floor, adobe walls, and a tile or corrugated metal roof. Small, usually shuttered windows leave the interiors dark and often smoky from cooking fires. Most houses have a sweatbath, and Mam bathe as often as the availability of firewood allows.