The article above by reporter Carl Zimmer is titled “Monogamy and Human Evolution,” and it centers on the reasons and effects that primates such as humans began forming monogamous relationships after the split with our chimpanzee and baboon ancestors. Zimmer moves quickly from Dr. Dieter Lukas’s (University of Cambridge) research that animals would benefit from being less monogamous to Dr. Kit Opie’s (University Cambridge London) theory that humans evolved larger brains thanks to the addition of monogamous relationships. These may seem counter argumentative, but Zimmer continues, saying: “Each species faces its own special challenges — the climate where it lives, or the food it depends on, or the predators that stalk it — certain conditions may favor monogamy despite its drawbacks.”
After reading the first paragraph, I was slightly confused by the article’s neglecting to address how overpopulation is currently a huge issue with humans and certain animals. I understand that maximum reproduction is often a sign of being the fittest, and thus those who produce more offspring are less likely to become extinct. At the same time, it’s been proven time and time again that one of the largest factors in extinction comes from overusing resources. My initial concern was then gratified by Zimmer’s description of different theories that scientists have gathered on why animals evolve into forming monogamous relationships (i.e. females being more widespread vs. the threat of infanticide). Dr. Opie’s explanation that many animals may face infanticide directly relates to my qualm: since fathers began sticking around to provide food and protection for their offspring, it means they were concerned about his offspring’s livelihood in respects to other predators. If fathers leave after every mate, than the likelihood of their offspring surviving decreases. That in it of itself decreases that specie’s ability to be the fittest.
Along these same lines, Zimmer then explains the aftermath of primate fathers first beginning to care for their children: “The extra supply of protein and calories that human children started to receive is widely considered a watershed moment in our evolution. It could explain why we have brains far bigger than other mammals.” Is it also possible that if more species start forming monogamous relationships, that natural selection will allow other species to evolve into more human-like animals? Or would this contradict Dr. Lukas’s idea that monogamy, even in the 9% of mammals that adhere to it, prevents male mammals from having more offspring, “mating with lots of females,” and thus being the fittest?
At first read Zimmer’s rhetoric is slightly confusing because of his contradicting reports that monogamy is less beneficial and yet also caused the development of current day humans. Though after reading it again, I realized that the stark change from one piece of evidence to the next completely coincides with how theories of evolutionary effects develop and adapt to newer evidence. Much like the theory of evolution itself, our understanding of how and why evolution takes place is continually changing and growing. The idea that monogamy can be beneficial to one species and harmful to another is certainly not new, and is even reinforced by University of Montreal’s Bernard Chapais’s statement that, “The human mating system is extremely flexible.” Even within species, mating systems and monogamy isn’t always consistent. This fact too proves the idea that evolution is constantly, and will always, force animals and humans alike to adapt to their current needs and surroundings.