Polygynous marriages fall into two types: "sororal polygyny", in which the co-wives are sisters, and "non-sororal", where the co-wives are not related. Polygyny offers husbands the benefit of allowing them to have more children, may provide them with a larger number of productive workers (where workers are family), and allows them to establish politically useful ties with a greater number of kin groups. Senior wives can benefit as well when the addition of junior wives to the family lightens their workload. Wives', especially senior wives', status in a community can increase through the addition of other wives, who add to the family's prosperity or symbolize conspicuous consumption (much as a large house, domestic help, or expensive vacations operate in a western country). For such reasons, senior wives sometimes work hard or contribute from their own resources to enable their husbands to accumulate the bride price for an extra wife.