The Grandmother Effect 2.0

My maternal grandmother c. 1970

My maternal grandmother c. 1970

I anticipated the moment; I received advice from sisters and friends; I read accounts; I remembered my own grandparents; I thought of my parents as grandparents. Yet, nothing, absolutely nothing, prepared me for the deep love I felt when I first held my long, skinny five-week-old grandson. Three years later, that experience was repeated when my dark-haired granddaughter was placed in my welcoming arms. I’ve had many roles in my life, daughter, wife, mother, lawyer, philanthropist, friend, sister, confidante, runner, and writer; being a grandmother is the most privileged position imaginable.

These two young humans capture my heart each time I am with them. They amaze and inspire me. They test my patience. They stoke my curiosity. They stretch my brain as I try to answer their hundreds of questions. We cuddle together to read books. We hold hands when we walk to the coffee shop. We run on sandy beaches. We color and draw and play with trucks. We sing silly songs. I try to divert their energy and calm their excitement when they are too wound up, sometimes successfully, other times not so much. But later, we smile and hug! All is forgiven.

I am a grandmother, in fact and in my heart. In ancestral societies, elderly women living with or in close proximity to their grandchildren helped nourish them, enabling survival and a chance at adulthood (known as the “grandmother effect” or “grandmother hypothesis”). In more recent times, at least in industrialized, Western cultures, grandmothers generally engage with their children at a level at least once removed from the primary caregiver role, although they are often the first adults, other than parents, with whom young children interact. A grandmother’s role has evolved from ensuring the basic survival of her grandchildren to a more complicated relationship (what I’ve designated as the “grandmother effect 2.0”).


Basic evolutionary theory posits that there should be no natural selection for living beyond one’s reproductive capacity. In most animals, the end of a female’s reproductive years (“reproductive senescence”) is concurrent with the end of her life. Yet, female humans (and a few whale species, e.g., Orcas, Beluga, and Narwhals) often live long past menopause. For many, this post-reproductive period may be a third of our lives. In ancestral human communities, the survival, co-residence, and/or assistance of a grandmother was invaluable to her families. Daughters weaned children earlier, enabling successive pregnancies; childhood mortality rates decreased; and children lived longer lives.

My grandmothers were raised by their respective grandparents in early twentieth century New York City, both of their mothers having died at the age of 34. The life expectancy at birth for white males and females born during that period in the US (1880-1890) was 47.8 years; each of my grandmothers lived into her nineties, well beyond what was expected. Together, they had seven children who lived to adulthood, five of whom also lived into their nineties (including my parents); the other two died in their seventies of life style diseases. We often “bragged” about the longevity in our family, secretly hoping it was an inheritable trait.

The synchronicity of my grandmothers’ lives intrigued me. Was their longevity mere coincidence? The result of the grandmother hypothesis? Genetics or epigenetics? Some other type of selection? What about the social role (as distinct from an evolutionary role) that their grandmothers played in their lives? Is proximity critical for a grandmother to have influence on her grandchildren? I live two thousand miles from my grandchildren, seeing them in blocks of time as opposed to near-daily contact. Does this make a difference in my role?

The grandmother hypothesis, which was first elucidated in the early 1950s, was an adaptationist explanation for the fact that human females lived long post-reproductive lives. Rare in the animal kingdom, an explanation was sought for this post-menopausal period and its evolutionary fitness. At its height of popularity, scientists reasoned that this long post-reproductive period might have evolved as a consequence of grandmothers foraging for food and sharing it with their daughters. This enabled greater resources for the daughters to gain fitness benefits, whether by increasing the number of their offspring or by ensuring their children’s survival to adulthood. This in turn increased the fitness of grandmothers by enabling them to share genes with her grandchildren. An intriguing outcome, having the ability to influence future generations (extending longevity for both males and females) other than by direct reproduction.

Unfortunately, the elegant theory of the grandmother effect has had varied results, from positive, to negative, to neutral. There are a number of reasons for this variety. Initial research focused on grandmothers in insular, tribal societies, where survival and decreased infant mortality were the key focus of grandmothers. In patrilineal societies, grandmothers may have more incentive to help male children and grandchildren in order to continue the paternal organization. Conversely, some research shows that the grandmother effect likely favored maternal grandmothers, where the direct hereditary link is more clear; daughters are more likely to seek help with their children from their mothers than from their mothers-in-law.

The respective ages of a grandmother and her grandchildren may impact involvement. Elderly grandmothers may be unable physically to care directly for their grandchildren, or may be a distraction in the family unit because of their declining health, or may not have the financial or other resources to help with grandchildren. The degree of X-relatedness between grandmother and grandchildren has been considered as a potential influencing factor. Because of genetic-relatedness, grandmothers may invest more time in their daughters’ children than their sons. A study in Indonesia found that grandmothers appeared to focus their help on more needy children and grandchildren. And certainly, cultural differences and reverence for multiple familial generations impact the role of grandmothers within families.

The longevity of my maternal and paternal grandmothers and the coincidence of their both being raised by their grandmothers likely doesn’t have scientific validation, given the research described above. Yet, they both contributed to whom I am. I felt safe and accepted because of my paternal grandmother’s warmth and concern in what I was doing.  My maternal grandmother encouraged my curiosity and exposed me to experiences outside my daily world. I want to bring these attributes to my relationship with my grandchildren, being a trusted adult who makes them feel safe, who accepts them wholeheartedly for who they are, who listens without judgment (unless their choices are dangerous or harmful), and who encourages them to explore the world beyond their doorsteps. And of course, my grandmothers’ longevity is at the forefront as I think about being a grandmother: how much time will overlap between my grandchildren’s lives and mine? What and how many opportunities will we have to be together? How will we share those moments?

There is no scientific blue-print as we contemplate what it means to be a grandmother today, given that the historical fitness measures are no longer necessary in most societies. We have blended families, where children may have several sets of grandparents. We have two-career families where people (“alloparents”) other than biological parents care for the children. We have grandparents who are financially able to help with their grandchildren’s college or health care expenses, lessening the burden for the parents. We have grandparents as the primary caregivers of their grandchildren (“kinship” providers or “grandfamilies,” terms well known in the foster care system), whether due to their children’s substance abuse, incarceration, or death. These roles may be undertaken at a time when the grandparents themselves are preparing for retirement, or living on a limited income, or dealing with a disability, or living in housing unsuitable or too small for grandchildren.

Traditionally, research into the role of grandparents has been narrowly focused. A recent study called for a more comprehensive, interdisciplinary framework for studying grandparental investment in their grandchildren. Hundreds of individual accounts and projects, from anthropologists, biologists, economists, and sociologists, attempt to keenly answer the question: why do grandparents invest in their grandchildren in the twenty-first century? What is my self-defined grandmother effect 2.0?

The theories are numerous, the results often inconclusive or contradictory, the recommendations for additional research clear. The different theories force us to be thoughtful and flexible in our relationships with our grandchildren. They provoke consideration of alternative ways of being with our grandchildren than what we might otherwise consider. For me, the grandmother effect 2.0 is ultimately a simple formula: to love, protect, and share the lives of two little ones who are a part of me.


My grandson is five-years-old, all legs, with boundless energy, proud of his “pedal” bicycling skills, able to run for miles, learning to become a big brother to his sister with less poking and provoking, listening to audible books (currently, ‘The Wind in the Willows’), his huge imagination creating the pictures of the characters while he listens, helping bake cookies (his task, to stir), asking question after question after question, my son and daughter-in-law so patient in their answers, showing his preferences in music, excited to see friends and family, crashing into them with his big hugs, always talking and chatting, so full of “stuff” inside his brain that needs to come out and be expressed, sometimes exasperating, always wondrous.

My almost two-year-old granddaughter is vital and independent, a big smile between her chubby cheeks, except when she howls in anger, her silky hair tied in tiny bunches straight up on her head, singing and chatting non-stop, taking in each minute of every day, sleep a nuisance and distraction, mimicking her older brother and parents, swaying to any music that she hears, riding her glider bike four blocks to school, her short legs pumping, excited when she sees a dog, even blocks away, fearlessly climbing up and down the mahogany staircase of their house. She has a big personality and will be a force.

I truly believe that spending intense, quality time with my grandchildren improves (or at least maintains) my physical health and mental well-being , a two-way street. I hope both my grandchildren continue to expect that Gaga PB can run with them on the sandy beach, hike a mountain trail, ride a bicycle to the Arboretum, play hide-n-seek in the bushes behind their house, or answer their never-ending questions. There will be a time when I am unable physically —and perhaps mentally—to keep up with them, but it won’t be for lack of trying. I want them to have memories of active, older people who remain curious, who appreciate a child’s wonder, who bend down to their level to listen to them, who love them without reservation.

My life is made fuller by the presence of my grandchildren. I ache to be with them within days of our most recent visit. I want to learn about their school days, their friends, their mishaps, their curiosities, their unending questions, their current favorite song. I want to be present in their lives as much as possible without overstaying my welcome. I want to provide them opportunities to learn, to play, to take risks, to be independent, to be unique, to be kind and empathetic human beings. I want to protect them in our rapidly changing world, to give their parents the support they need to nurture these precious children. Most of all, I want to be a person with whom they can share the burdens, the joys, and the wonders of childhood, now and into the future. This was demonstrated only recently, when my grandson said to his mother on a long airplane flight to my house: “I want to talk to Gaga PB right now!”









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