The song about grandmas that I remember best from childhood involves the great dame drinking too much eggnog and getting run over by a reindeer on Christmas Eve. Here, let YouTube take you back:

Yet, according to the New York Times, that popular image needs an upgrade. In the revised version, Grandma wouldn't be getting into trouble by imbibing too much eggnog. She'd be too busy working. Given all the work that they do, post-menopausal women may actually be an evolutionary secret weapon.

"Today many women feel marginalized once they reach menopause," says the Times' Well blog. "But research suggests that far from being a burden to societies, grandmothers have played an important role in the evolution of human longevity. Studies of modern hunter-gatherers in Tanzania, Venezuela and Eastern Paraguay -- societies that offer insights into how humans evolved -- consistently show that Grandma is doing much of the work. Researchers have even measured the muscle strength of men and women in these communities and weighed the baskets and bundles carted around by them. Often, the scientists find, "women in their 60s are as strong as women in their 20s." For more on the grandmother hypothesis as conceived by anthropologist Kristen Hawkes of the University of Utah, click here.

In modern societies, do we see traces of the edge that grandmas give in the thousands of hours of free childcare, endless gifts or fat college funds showered on grandchildren? Far from spending their dotages in a rocking chair taking it easy, these older women are doing a lot of work to help out the younger generations.

Positive spin: All hail, Grandma! What would we do without you? Kisses!

Negative spin: Grandma, I hope you weren't looking forward to kicking back during your retirement. Jeez, a woman's work really never is done.