Genetic evidence that humans' "default state" is not solitude

Environment plays a key role in how our genes behave. Now evidence is mounting that our social world is part of that environment, and that interpersonal connection shapes the gene expression in animals from bees to humans. In humans, a lack of social connection can even compromise the immune system.

Photo by Stargazing Adventures

Over at Pacific Standard, science journalist David Dobbs has a thoughtful, intriguing article about Steve Cole, a psychology researcher who has devoted his life to exploring the social dimension of genetics. Cole and his colleagues have studied bees, birds, monkeys, and humans — and they've found that social connection triggers a telltale cascade of activity in a suite of over a hundred genes, some of which are shared across these species.

When birds hear each other sing, for example, researchers find changes in genetic expression within minutes. Similarly, humans who report feeling socially disconnected and lonely show a very different range of genetic activity than socially connected people.

Dobbs writes:

Why would we have evolved this way? The most probable answer is that an organism that responds quickly to fast-changing social environments will more likely survive them. That organism won’t have to wait around, as it were, for better genes to evolve on the species level. Immunologists discovered something similar 25 years ago: Adapting to new pathogens the old-fashioned way—waiting for natural selection to favor genes that create resistance to specific pathogens—would happen too slowly to counter the rapidly changing pathogen environment. Instead, the immune system uses networks of genes that can respond quickly and flexibly to new threats.

We appear to respond in the same way to our social environment. Faced with an unpredictable, complex, ever-changing population to whom we must respond successfully, our genes behave accordingly—as if a fast, fluid response is a matter of life or death . . .

We sometimes conceive of “social support” as a sort of add-on, something extra that might somehow fortify us. Yet this view assumes that humanity’s default state is solitude. It’s not. Our default state is connection. We are social creatures, and have been for eons. As Cole’s colleague John Cacioppo puts it in his book Loneliness, Hobbes had it wrong when he wrote that human life without civilization was “solitary, poor, nasty, brutish, and short.” It may be poor, nasty, brutish, and short. But seldom has it been solitary.

What's intriguing is that all these socially-activated genes are also associated with the immune system. Without social connection, our immune system responds more weakly to threats — and this leads to a host of problems. The good news, writes Dobbs, is that we can change our genetic expression and immune responses by changing our social behavior.

Find out more about how that works by reading the whole article over at Pacific Standard.