A study conducted by scientists from the Hubert Curien Pluridisciplinary Institute of the French CNRS shows that about 70 million years ago, when dinosaurs existed, the ancestors of primates usually lived in pairs and only 15% of them led a solitary lifestyle.
The discovery that our ancestors adopted different forms of social organization challenges the previously generally accepted hypothesis that they lived alone at the time and that life as a couple developed much later.
The authors think it's likely that living as a couple brought significant benefits, such as easier reproduction and reduced costs of thermoregulation while “cuddling” with each other. Their conclusions were recently published in the journal PNAS.
Learn more about the social evolution of the species
Although several studies have been conducted on the social organization of primate ancestors, this is the first to use only currently available field observations.
By studying 498 populations of 223 species, the team has built the most accurate primate database to date. For experts, “this project paves the way to better understand the social evolution of the human species.”
Reference: Alternating current. Olivier et al.: “Primate social organization evolved from a flexible, pair-living ancestor.” PNAS2023.