We currently believe the reason for social monogamy in mammals is that it allows for the ensured passage of genes from parents to offspring. Females are the only ones that are guaranteed to know which offspring is theirs, so monogamous relationship allows for males to know as well. Longer parental care as a result of monogamy increases the survival rates of offspring through nurture and protection, thereby increasing the chance of their genes being passed on, which is Darwin’s sole purpose of life.
Opie, Atkinson, Dunbar, and Shultz determined that high male infanticide rates are the sole cause of social monogamy. Their support is that social monogamy lowers infanticide rates because it allows both parents to defend their offspring. Shorter lactation times are associated with social monogamy, which also reduces infanticide rates.
Lukas and Clutton-Brock determined that intense feeding competition between females, intolerance between breeding females, and low population densities make it advantageous for males to have monogamous relationships. They acknowledge the connection between social monogamy and low male infanticide rates, but claim that it is not a primary factor.
Lukas and Clutton-Brock have a more convincing scientific argument. Their claim that other factors working together contributed to the development of monogamy makes more logical sense than Opie and others’ claim that male infanticide is the sole cause of social monogamy. Lukas and Clutton-Brock support each argument with relevant data which clearly show a direct relationship between the data and their analysis. Opie and others have less data and support for their arguments and are unclear in their data analysis.
These articles have not really changed my understanding of monogamy in primates. We have already discussed multiple advantages in class supporting monogamy, such as the guaranteed passage of traits and the increased survival rates of offspring. What surprised me, though, was that social monogamy developed first and increased parental care followed after, rather than vice versa, which the latter seems more logical in my mind.