How Much Did Grandmothers Influence Human Evolution?

The seeds of an idea were planted as Kristen Hawkes watched older women collecting vegetables. Hawkes, a professor of anthropology at the University of Utah, has extensively studied the Hadza, a group of hunter-gatherers in Tanzania who eat a lot of wild foods such as berries and tubers. While young children can pick berries themselves, older women in the community are the ones pulling up the bulbous root vegetables, which would be difficult for young kids.

Hawkes found a correlation between how well children grew and their mother’s foraging work, until the mother had another kid. Then, their growth correlated with “grandmother’s work,” she says. “There were the data right in front of us.”

Read more