The Evolution of Social Monogamy in Mammal and Male Infanticide lead to Social Monogamy in Primates are both scientific journals that discuss the increased occurrence of social monogamy amongst species, especially primates, with an overwhelming quarter of the primate species being socially monogamous. Evolution has evolved for some mammals to favor the survival of their offspring rather than the male chances at reproducing with other females, also known as iteroparity. There have been some theories that have developed over time that scientists can attribute to the perpetuation of social monogamy such as the cost of raising offspring is significantly higher forcing mothers to rely on group care, the ranges of territory in which the females roam making it harder for males to mate with more than one female, and what is considered the most compelling explanation for social monogamy, male infanticide. In order for this to be perpetuated, there must be some type of advantage to not only the offspring, but to both parents as well. In primates, when males help with child rearing the females lactation period shortens due to the decrease of energy needed to take care of her offspring, increasing milk flow. The mother not only is able to wean the infant earlier, but her and the father are able to ensure that their offspring will live until it has reached the age of maturation, and the female can get back to estrus sooner.
Although both articles discuss the evolution of social monogamy as a reader The Evolution of Social Monogamy in Mammals written by Lukas and Clutton-Brock would have to be the more scientifically credible source as they not only give a hypothesis and background information, but they also are sure to include a vast amount of data to back up any theories they might have had and allowing the reader to draw their own conclusions from the data. Unlike Lukas and Clutton Brock’s article Opie article includes very little data and tries to support their theories by listing reasons as to how both the parents and the offspring benefit from socially monogamous relationships.