From the readings in textbook and discussions in class, I have come to the conclusion that the reason for social monogamy in mammals is to ensure the survival of their offspring. Since mammals are K-strategists they exhaust more energy into the survival of their offspring rather than the total number of offspring. Since the Darwinian biological destiny for all organisms to pass along their genetic makeup, it is in the best interests of both the mother and father to care for their offspring and sticking to one partner increases the probability of raising a viable fertile offspring.
From the title, it is safe to assume that the first article, Male Infanticide Leads to Social Monogamy in Primates, states that the cause of social monogamy in primates was due to infanticide by competitive males. In order to ensure the survival of their offspring, males would protect newborns causing a shift to social monogamy and lowering rates of infanticide in these groups. On the other hand, the article written by Lukas and Clutton-Brock states that, “social monogamy has evolved in nonhuman mammals…where males are unable to defend access to multiple females” (pg 1).
I believe that the Lukas and Clutton-Brock article makes the better argument due to, among other reasons, addressing the hypothesis of infanticide from the other article and attempting to disprove and stating that, “although the prevalence of male infanticide is lower among socially monogamous species (9%) than among solitary species (27%), it does not appear to be a consequence of a direct association between social monogamy and male infanticide due to the suggestion of an independent evolution of the two traits” (pg 2).
These articles have provided me with very detailed thoughts and analyses of social monogamy in primates though I would not say that they radically changed my understanding of the topic. However, I was surprised to learn from the readings as well as discussions in class how little socially monogamous nonhuman mammals there are (3%). I had never thought about population density affecting the probability of social monogamy and the Lukas/Clutton-Brock article addressed that higher population densities are less likely to become socially monogamous which I found very interesting.