Here are Linda and me at a restaurant with our grandson Ethan. He’s eight in this picture; now he’s nine. We love being grandparents. Among other things, Linda is his confidant and storyteller and I’m a grownup playmate. Recently I read an article by Rachael Caspari entitled The Evolution of Grandparents (Autumn 2016, Scientific American Special Collectors Edition) that provided some new and surprising information about the significance of grandparents in the development of our species.
She says that “living to an older age had profound effects on population sizes, social interactions and genetics of early modern human groups and may explain why they were more successful than archaic humans, such as the Neandertals.” Examining fossils from three million years ago, she and her colleagues found that individuals of this latter group, with few exceptions, didn’t live beyond 30—the age when archaic people lived long enough to become a grandparent.
Dying young was the rule for millions of years, and over that span of time there was a gradual increase in longevity among many of the groups they studied. Still, it wasn’t until around 30,000 years ago, very late in human evolution, that survivorship soared—among the modern humans of the European Upper Paleolithic.
While the researchers haven’t yet discovered the reason why this European group doubled their survivorship ratio compared to other groups—despite their living in much harsher conditions— they found that the increase itself had far-reaching effects. And here’s where the study gets really interesting in terms of our being and having grandparents.
In studying several modern-day hunter-gatherer groups, Kristen Hawkes at the University of Utah, and Hillard Kaplan of the University of New Mexico and others “found that grandparents routinely contribute economic and social resources to their descendants, increasing both the number of offspring their children can have and the survivorship of those children. Grandparents also reinforce complex social connections.”
For example, when grandparents tell their grandchildren stories of deceased relatives, they link them to the family history in a context of what the world was like back then. These and other stories of personal and social challenges successfully met, provide young people a sense of security and continuity. A grandparent can even help a more mature child appreciate that his standing on the shoulders of the past is a privileged position, from which he can reach for his dreams with confidence. Indeed, each new generation stands at the leading edge of human evolution.
Specifically, the author talks about early human elders transmitting information about the environment, teaching grandchildren which plants and snakes were poisonous and where to find water in a drought. While parents were out hunting, gathering or building shelters, the grandparents were educating their children about how to weave a basket or knap a stone blade.
Among her conclusions: “Multigenerational families have more members to hammer home important lessons. Longevity presumably fostered the intergenerational accumulation and transfer of information that encouraged the formation of intricate kinship systems and other social networks… Longevity resulted in increased population size by adding an age group that was not there in the past…Large populations are major drivers of new behaviors…and population density figures importantly in the maintenance of cultural complexity…Larger populations promoted the development of extensive trade networks, complex systems of cooperation, and material expressions of individual and group identity (jewelry, body paint, and so on).” What I take from this is that about 30,000 years ago, the advent of grandparents had a rising and cascading effect, compounding complexity, increasing survival prospects and passing on history, practical information, skills and wisdom in every facet of everyday life, both personal and social.
And significantly, according to Dr. Caspari, “growing population size accelerated the pace of evolution. More people means more mutations and opportunities for advantageous mutations to sweep through populations as their members reproduce. This trend may have had an even more striking effect on recent humans than on Upper Paleolithic ones, compounding the dramatic population growth that accompanied the domestication of plants 10,000 years ago.
The relation between adult survivorship and the emergence of sophisticated new cultural traditions was almost certainly a positive feedback process.. .Longevity became a prerequisite for the complex behaviors that signal modernity.” Indeed, it led to population expansions that had profound cultural and genetic effects ever since.
These findings prompted me to reflect on advances in the many contemporary fields of study and practice that are helping us live longer and healthier lives. On this turn of the evolutionary spiral, where technologies are outpacing our ability to keep pace with them ethically, I wonder if grandparents might have another role to play.
For instance, might we help the younger generation see that their electronic “toys” and tools can have a higher purpose? And can we help them to see that absorption in tools of any kind can be a distraction from what’s really important in constructing a meaningful, happy and contributing life? Thirty-thousand years after the innovation of grand-parents, both in speech and action, we are still offering the incoming generations the great gifts of stories about their ancestors and the wisdom of our experience.
Although Ethan was just being a kid posing for this picture, in the context of this contemplation I imagine him giving us a double “thumbs up” for having us in his life. Would that I could, I’d return the gesture. What a joy and privilege it is to have him in our lives.
Elders play critical roles in human societies around the globe, conveying wisdom and providing social and economic support for the families of their children and larger kin groups.