San settlements are composed of one to a dozen or more homesteads, each containing a set of separate households, the heads of which are ideally related as parent and child or as descendants of common grandparents, that is, as siblings and first cousins. Larger settlements may contain 200 or 300 persons. Many homesteads, as well as individual households today—and probably all of them in precolonial times—also set up temporary encampments near seasonal rain pools, from which their members hunt and collect wild-plant products; livestock are usually kept there as well, and fields may be cultivated nearby. In Botswana, settlements rarely contain only persons of a single language group; in Ngamiland, for example, Zhu I õasi, I Au I I ei, Nharo, Nama, Mbanderu, Mbukushu, and Tswana homesteads may all be found in the same settlement. Houses within a homestead are normally built close together and usually face a common open area, but homesteads within a settlement may be 2 to 3 kilometers apart; clients and persons employed as herders tend to live adjacent to their patrons and employers. Conical grass huts are frequently used, especially at temporary encampments, but round, one-room, wattle-and-daub houses with thatched roofs are more common among most groups.