The institution of marriage
The institution of marriage is both old and ubiquitous. Yet, little work has been done by economists on why this social institution exists and why throughout history it has been intimately linked to fertility. We explain the institution of marriage as a societal consensus on the need to curb cuckoldry for the purpose of paternity certainty and biparental investment in offspring. By raising the costs of mating to individuals, marriage reduces cheating in society, a source of mating market failure, and makes paternity more certain. Men, in consequence, invest more in their putative offspring, a fact that also benefits mothers.
Bethmann, D. and M. Kvasnicka (2011), The institution of marriage. Journal of Population Economics, 24, 3, 1005-1032