Monogamy may lead to improved infant care, since males are more certain about paternity, which typically results in greater bonding. Females then benefit too, since the male’s support lessens the burden of pregnancy and lactation.
The findings could help to explain how pair bonding arose in non-human primates and in our species.
To this day, not all human societies are monogamous, but “anthropologists still do believe that the pair bond may have been critical to the evolution of human societies,” Fernandez-Duque said. “In humans, the pair bond may be important for committing the partners to share space, time, labor, infant care and provisioning.”
Such relationships also seem to promote peace among larger groups. Titi monkeys, for example, are monogamous primates that are often described as living relatively peaceful lives. “Make love not war” can also benefit humans.
“Call it love, call it friendship, call it marriage," Fernandez-Duque said. "There is something in our biology that leads to this enduring, emotional bond between two individuals that is widespread among human societies.”
Agustín Fuentes, a University of Notre Dame professor of Anthropology, told Discovery News that the new research is “groundbreaking.”
“This report is particularly important because it demonstrates the value of the pair bonds in actual evolutionary relevant terms — reproduction. Being in the same pair, and having a robust pair bond is core to being a successful owl monkey.”
Fuentes added, “Monogamy is extremely rare as a social system in mammals, and it is through intensive and well-crafted work such as this that we are finally starting to see how such systems actually operate.”