Family formation is central to human life. Unlike other primates, humans have evolved complex networks of regulated exogamy, often including critical economic components such as brideservice or brideprice and low levels of polygyny.
Despite these differences, phylogenetic analyses are equivocal on whether ancestral hunter-gatherers had arranged marriages. However, maximum parsimony reconstructions indicate that early ancestral human societies had a combination of regulated and unregulated practices.
It was once common for a male forager to have multiple wives. This allowed him to collect bride services and bride prices while hoarding women’s productive and reproductive labor, allowing him to achieve a high status in his group and recoup his investment (Boserup 1970). But as brainy Homo evolved, it became more costly to defend large areas of territory for multiple females and their offspring.
Over time, laws and religious customs shifted toward limiting polygyny. As a result, the strength of sexual selection fell by about 58%. The decline coincided with a reduction in male mating success. It also corresponded with a shift from polygyny to monogamy in some societies.
The universality of marriage in hunter-gatherer societies suggests that it has deep evolutionary roots. The comparison of cultural phylogenies of well-studied hunter-gatherers shows that the same social exigencies favored regulated pair-bonding throughout our species’s history. Apostolou’s  comparative study of 190 hunter-gatherers found that arranged marriage by parents or close kin is the norm in 85% of these cultures and brideprice, brideservice, or some type of exchange between families exists in 80% of these societies.
The purpose of a bride price is to demonstrate the groom’s ability to provide for his wife and children. This tradition has been criticized for instilling in men an ownership mentality that may lead to ill treatment of their wives. The practice is still prevalent in parts of Papua New Guinea, which was famously studied by Bronislaw Malinowski.
The universality of marriage among hunter-gatherers suggests a deep evolutionary history of institutionalized pair-bonding. However, the actual practices of human marriage are extremely diverse from culture to culture. They vary from arranged marriages to largely unregulated courtship, presence of bride wealth to absence of it, and the existence or absence of polygyny and bride capture.
Bride wealth – also known as bride price or bridewealth – is the transfer of cash and goods from the groom’s family to the bride’s family before a wedding. Anthropologist Roger Keesing describes it as a central feature of patrilineal family systems that tie women’s status and reproductive rights to their kin.
This practice allows young women and first-time mothers to stay with their natal communities and help them get started in the community. It may also allow men to avoid the risks associated with marriage-by-capture.
Patriarchy is a system of power and privilege in which men as a category control, oppress, and exploit women as a category. This exploitation is perpetuated through gendered inequalities at all levels of society, from the law to the home. Patriarchy is also supported by powerful cultural norms, which reinforce the status quo and undermine progress towards equality.
Some researchers argue that patriarchy arose when hunter-gatherers began settling down and acquiring property. As people began living closer together, they needed to defend their homes and land. These changes gave more power to physically stronger males and shifted wealth into the hands of males. This allowed men to compete with each other for marriage partners and to form powerful families. This led to the emergence of polygyny and other male-dominated systems.
Phylogenetic reconstructions suggest that ancestral human societies had low levels of polygyny and reciprocal exchanges of daughters (brideservice, brideprice) among family members. However, there is considerable morphological and behavioral variation across hunter-gatherers. Moreover, ethnographic evidence shows that families often reassort daily and seasonally to include maternal and paternal relatives throughout a marriage union.
These patterns may reflect a combination of sexual and economic motivations. Specifically, men’s specialization in hunting is probably a coordinated outcome intended to complement women’s activities in a social division of labor. In addition, better hunters gain greater fitness gains within a marital union than outside it. This translates to higher social status and higher resource accruals for the household. Some of these benefits include childcare, coalitional support, and health insurance.