New research suggests monogamy in humans evolved as a means of protecting offspring from being killed by rival males.
For the study, a team from University College London, as well as universities in Manchester, Oxford and Auckland, gathered data across 230 primate species, largely observing their mating habits.
This protection meant the offspring, or children, were more likely to experience greater brain development, avoiding injury or death under the watchful eye of a father.
Rival males in non-monogamous communities will seek out a female’s offspring and often try to kill them as a means to encourage the female to mate.
Monogamous societies tend to produce healthier offspring in the wild, allowing for more intelligent and well-nurtured offspring. This trait in humans first evolved from monkeys, according to the findings.
“Monogamous societies tend to produce
healthier offspring in the wild.”
The authors believe this is conclusive proof that the main reason for monogamy in humans is also the protection of their children.
For the study, researchers essentially crafted an expansive family tree to determine which evolved traits surfaced first in primates.
They found males killing offspring at high levels likely led to large groups of primates transitioning from multi-mating to monogamy.
Later, the trait of each parent sharing the care duties of an offspring, as opposed to leaving nurturing entirely to the female, also evolved.
“This is the first time that the theories for the evolution of monogamy have been systematically tested, conclusively showing that infanticide is the driver of monogamy,” said lead author Dr. Kit Opie.
The study was published in the journal Proceedings of the National Academy of Sciences.
Source: pnas.org. Photo source: guim.co.uk.