Most mammalian reproductive patterns are polygamous, as the males invest in quantity of offspring over the quality of offspring in order to ensure that there is at least one female inseminated by its specific genetic information. However, there are clear advantages to monogamous reproduction as well, which as discussed in class include energy investment into a single organism and greater provision of resources for said offspring. If the male is beside the female through the entire process of reproduction, or even life, the male becomes just as invested in the offspring as the mother. These articles provided some new information, supporting not only reasons for monogamy that we were already familiar with but rather a shift from polygamy to monogamy and why that occurs.
The first article listed three hypotheses, yet later on went to elaborate that one-male infanticide-has true support where as the others are merely consequences of a shift to monogamy that has already begun to occur. Opie, Atkinson, Dunbar and Shultz explain infanticide’s benefit, saying, “Where oestrus is delayed, it can pay a male, who is not the father, to kill an unweaned infant so that the female returns to oestrus sooner.” Despite this evidence, the authors mention that a correlation is not a causation, and they do not prove that indeed one, or even all three, of the aforementioned behaviors support a shift into monogamy. Though the data present in the article exists in the form of Bayes factors and phylogenetic tests, the actual proof of causation is not supported. It is actually refuted within the very article. The data is also very limited and each aspect of their hypotheses is not properly addressed.
Unlike the first article, Lukas and Clutton-Brock maintain a more comprehensive conclusion. They illustrate “six transitions to social monogamy in primates,” each with its own data, sample size, and conclusions. Though both articles mention different influences, Lukas and Clutton-Brock’s decision to utilize all behaviors in their explanation makes their article more credible and more realistic. Also, in comparison this article had many more sources and was organized in a way that flowed more clearly and allowed for greater elaboration and detail.
Overall, monogamy has transgressed from my limited schema to a new understanding. I saw it as a human idea, one that was rooted in the psychological and emotional aspects of humanity rather than the physiological ones, yet now I see it as a scientific and animal concept. The different behaviors that support monogamy in mammals come together with what we have learned about K selection and R selection, and the different energy investments animals must make when focusing on their “only” goal in life- to reproduce and perpetuate their genetic information.