Laura Betzig (Evolution and Human Behaviour Program, University of Michigan, Ann Arbor Michigan)
Ethology and Sociobiology: Vol. 13:5-6 (1992)
Mating in Rome was polygynous; marriage was monogamous. In the years 18 and 9 the first Roman emperor, Augustus, backed the lex Julia and the lex Papia Poppaea, his “moral” legislation. It rewarded members of the senatorial aristocracy who married and had children; and it punished celibacy and childlessness, which were common. To many historians, that suggests Romans were reluctant to reproduce. To me, it suggests they kept the number of their legitimate children small to keep the number of their illegitimate children large.
Marriage in Rome shares these features with marriage in other empires with highly polygynous mating: inheritances were raised by inbreeding; relatedness to heirs was raised by marrying virgins, praising and enforcing chastity in married women, and discouraging widow remarriage; heirs were limited– and inheritances concentrated–by monogamous marriage, patriliny, and primogeniture; and back-up heirs were got by divorce and remarriage, concubinage, and adoption. The “moral” legislation interfered with each of these. Among other things, it diverted inheritances by making widows remarry; it lowered relatedness to heirs by making adultery subject to public, rather than private, sanctions; and it dispersed estates by making younger sons and daughters take legitimate spouses and make legitimate heirs. Augustus’ “moral” legislation, like canon law in Europe later on, was not, as it first appears, an act of reproductive altruism. It was, in fact, a form of reproductive competition.