E117: The Social Domain of Perimenopause

Katie: You've heard it before. It takes a village to raise a child. But the village has always run on a particular engine, and her name is Grandma, or Nana, Gigi, Abuela, Oma, Nona, or Yaya. But the grandmother is one of the few human relationships that every culture independently cherishes and gives its own name to.

In my family, I'm Nana. But here on this podcast, I'm Katie Ward. I'm a professor at the University of Utah College of Nursing, and I'm a practicing nurse practitioner in women's health. And with me, as always, is Dr. Kirtly Jones, who's a professor of obstetrics and gynecology at the University of Utah.

Kirtly, what's your grandmother name?

Kirtly: I wanted Bubby. It fit my soft and round persona as a grandmother, Bubby. And it's easy. "Bubby," "ba-ba-ba," it's easy for babies, but it's Yiddish. And I figured that was cultural appropriation. So I chose Nana, which is the most common word actually. About 10 to 15 cultures and languages use Nana or Nana, and it's easy for babies. "Na" is probably as easy as "ba." So I'm Nana, although in my heart, I'm a Bubby.

Katie: Bubby. Aw, I like that.

Well, welcome to the "7 Domains of Women's Health." We are continuing our work through the 7 Domains of Perimenopause, one domain at a time. And today we're on the social domain.

I actually think the social domain might be the most important one because there's a really serious and interesting scientific case that the entire reason that human women live long after their last period and go through all these changes that we're talking about that are the perimenopause is due to social pressures, social needs.

And so as far as we know right now, only humans and five kinds of toothed whales go through menopause. And there's a very specific set of social pressures that create the conditions where menopause is a good idea. And Kirtly, I know you know some things about whales.

Kirtly: Well, I'm thinking about orcas. Orcas are a little easier to follow because there are residential pods that are close to shore. There are pods of orcas that are out in the ocean and they're hard to follow. So orcas belong to the dolphin family, but they're cetaceans.

When you look at orcas, they have very similar ages of puberty in their teens. They have big brains. They have a lot of adolescent learning and the mothers, the moms, the nanas run the pod. They have language and dialect. Different pods have different kinds of sounds.

And so this is what we might call parallel evolution in the sense that we are not related in any sort of formal way genetically to orcas, but something must have happened that was an advantage for orcas to actually live so many years in a social structure where the females run the show, where they use language, where they have many years of learning, and they have very sophisticated hunting techniques.

It tells us a little bit about what the importance is of these last 30, 40, 50 years in our lives. And so I think it's pretty interesting as to what do we learn about ourselves, what are parallel kinds of designs that orcas have and other toothed whales.

Katie: Yeah. And I think so much of what I hear right now sort of describes perimenopause as this impending catastrophe that's happening. But I think there's some really fascinating work about why we have menopause.

And so we are really excited that today we have the author of what we call the Grandmother Hypothesis, who's our guest today. I'm very excited about this.

Dr. Kristen Hawkes is a distinguished professor of anthropology here at the University of Utah and arguably the world's leading expert on why we have menopause. She's the author of hundreds of papers and cited in the thousands, 20,000s of times by other people. If you're going to write about menopause, you've heard of Dr. Hawkes. And I'm so excited that she's going to be here with us today to talk about this. Welcome, Kristen.

Before we talk about orcas, I want you to tell us a little bit about you. You came to study this question about menopause, but I don't think that was what you were studying originally as a new anthropologist. What were you studying that got you into this at all?

Kristen: It was the hunting hypothesis, the story of how we got to be different from the other primates in general, but the story has been an extremely influential one. If you're looking at most mammals, and certainly most primates, you've got mom and that little one, at least for a while. But what happens with us is dad now is . . . hunting is a better way to make a living, bring home the bacon, so mom can have a lot more kids and be completely supported by a dad who's paying the bills.

So here we were collecting all these data from the Ache and, whoa, not what was happening.

Kirtly: Well, what we see is so colored by our own experiences, our own cultural experiences at the time of the '50s and '60s. And so until you actually get the data, and look at the data, see who's bringing home the calories . . . Kristen, that was so amazing that you found who brought home the calories.

Kristen: Let me just say what we found with the Ache was that men and women were in general paying attention to different resource types. Although everything that women took, men also took sometimes, so we could make comparisons there. But what the guys got didn't go to their wives and kids, especially. Their wives and kids didn't get any special share. Nothing like the expectation that these guys were making choices to support their own wives and kids.

Here were these results. What the heck is going on? So how do we even begin to think about the fitness-related payoff that could account for what's going on there while we were doing what's called scan sampling of what everybody was doing while they're in the residential base. And then we were following people when they left and how much time they spent and all the things that we knew we needed to measure for these resource choice questions.

But I was following the women, and the women and kids were doing the very thing that James Woodburn, who had started working there in the '50s, had described. He said, "The women and children, they go off and feed themselves, may not bring anything back to the base camp because they're eating there. The men go off and feed themselves, but mostly they're going after the big animals." He had already described that.

Well, he wasn't quantitative, and we were. I was trying to see what kinds of return rates the women were getting for what turned out to be the year-round staple, these deeply buried underground storage organs, these roots, the particular vigna, that is the main staple. It's these enormous things, like five kilos. It's way bigger than a potato.

But anyway, because I was paying attention to . . . and we didn't have any demography to speak of, but there it was, these old ladies, these women, who were clearly postmenopausal. I was guessing they were in their late 60s or 70s, and their return rates were the same as the women in the childbearing ages.

And so reporting those quantitative data, that was the first paper where we talked about grandmothers. That was in 1989, "Hardworking Hadza grandmothers."

And these Hadza kids, extremely active foragers. In fact, initially, I was describing all that stuff they were doing as play, but it turns out that they're too small, not strong enough. And we have datasets to show that this is what matters. It's not that they're not smart enough or haven't learned it yet. It's that they're little. And so digging these deeply buried year-round staple is just beyond them. They can't.

And our weights then showed that the weaned kids, how well they were growing, depended on their mother's work until she had a new baby. And then that disappeared and the correlation was with grandmother.

Kirtly: So Kristen, it seems like these people let you watch them, weigh them, follow them around, and see what they could dig up. And in the end of the day, if women had a mother who was there to help her feed the kids that she had that weren't breastfeeding, those kids were more likely to survive. Do I have that right?

Kristen: It was because the productivity of these women allowed their daughters, nieces, the younger, still-fertile women to have next babies sooner. But it should be the case if that postmenopausal period is about raising the rate of baby production, then the other invariant of [Charnov's 00:10:04] ought to be really different for us.

Our birth intervals are so much shorter, about three times any of the other. It was really the connection between shorter birth intervals and postmenopausal subsidies. So not babysitting. It was never babysitting. It was the support for the dependent kids.

So this is another thing our Hadza work was showing. The babies are starting to feed themselves before they're weaned, which is what goes on with most mammals. And then when they're weaned, they're independent feeders. Mom has another one. Well, not in this ape.

And so this thing about having another one when the previous one is still dependent, that works and selection is going to favor it as long as the previous one isn't going to die, when suddenly they're, "Wait a minute, I need that too."

That turns out to be such an important part of what makes us human, which is part of the story that I . . . So I want to talk about all of the pieces that go with this. Initially, all we saw was this connection between the economic productivity of the older females and the shorter intervals and, consistent with Charnov's model, the slower development. We're bigger than chimpanzees or bonobos, with whom we have the closest common ancestor.

Kirtly: I think it's interesting because the work that you did was with the closest we have on the planet of hunter-gatherer societies from whom we became Homo sapiens culturally, was from this process. But I think even data that has accumulated here in Utah show that even pioneer women, even in early settling here in Utah, if there was a grandmother around, the wives could have more children close together. So even contemporary data shows the importance of the grandmother.

And the grandmother doesn't have to be the biological grandmother. This is one of my favorite concerns in contemporary life, is that women who are past their reproductive age add an enormous amount to the growth of families and children and society. They're just so important. They have accumulated knowledge. They know where the tubers are usually found. They know how to get around Walmart or Target or whatever. They just make it go. They're the ones who make it go.

Katie: And if you didn't have a library, what you had was knowledge stored in the elders' brains, right? So if you have these hardworking mothers who know where the tubers are and how to dig them up . . .

And I think the other thing you said, Kristen, that I think about too is the fact that they were digging them up. These were strong women without frozen shoulder who were able to dig up tubers.

Kristen: It was the old women who were spending more time at this especially hard work, digging these deeply buried tubers. There are lots of other things that are very seasonal. This is the one that's throughout the year, really crucial.

But I also want to say . . . and this is a continuing problem, language. To talk about these as post-reproductive years is really to miss the argument that comes out of our Grandmother Hypothesis, which is what was going on with those ancestral grandmothers was they were reproducing copies of their genes in more of those in future generations.

And this whole thing about post-reproductive, then we get into all of these things about what are we talking about with reproduction? Well, Darwin included how surviving to produce offspring was really crucial and selection was going to operate on how that worked in different contexts, but also that mating and the effort that's put into that is also a way you get your genes into future generations. And he thought that was important enough that he wrote a whole separate book about it.

Our initial advantage we took of Charnov's model was focusing on women, the female side. Those were the data he was using in his mammal model because who's your daddy is always pretty tricky. It was pretty tricky for there to be enough data on what was going on in life histories of other animals to accumulate enough data for him to develop his models.

But we are sexual reproducers. We all get half of our genes from mom, and she got half of her genes from her mom, but we also get half of our genes from dad.

And it was another lucky break for me that there had been a paper . . . I was actually asked to review it, and I had been so confused about what this model was doing. It was a two-sex model.

So a two-sex model, now we start to bring in this other aspect that is such a feature of this ape that we got all these old men, and they are still producing sperm. What happens is the sex ratio in the fertile ages, which in most mammals is female biased for reasons that we could talk about why it usually is. Males are doing all these . . .

Kirtly: They're doing all this stupid stuff and getting killed, so . . .

Kristen: All that is happening. So now we've got all these old males still producing sperm, and of course the only place they're going to get paternities is on the still-fertile females.

And so what happens as a consequence of that, if you're looking at it from the perspective of the Grandmother Hypothesis, is it is now . . . A way better way to increase the chance of paternities is to claim a female and guard her. That advantage goes up if the intervals are shorter, because you don't have to wait so long for the next one.

Kirtly: The thing that makes us unique as primates is this long post-reproductive . . . It's not post-reproductive because grandmothers are still reproducing through their daughters. They're still helping their daughters make babies.

Katie: And the males are reproducing, Kirtly.

Kirtly: Right. We'll call it the postmenstrual years. I think that I even like that better.

What marks our culture is that many of the nanas kept the institutional memory of how to make things, of how to cook things, and were there constantly doing the work. Raising children and breastfeeding is a huge caloric and cognitive sink, so the people who had a brain that worked during these postmenstrual times were the grandmas.

And I think my personal bias is that if you look at who runs departments, women who run corporations, women who do stuff . . .

Katie: Women who make podcasts and write papers.

Kirtly: Women who make podcasts and write papers, they are often postmenopausal. So it's not just biological grandchildren. We as postmenopausal women help everyone rise. The rising of the women means the rising of the race.

I think that's what was so profoundly interesting about your work and all of your colleagues. It helped me understand a little bit as a menopause specialist about why women in the perimenopause and the postmenopause are so important to take care of. We need to take care of them, and we need to let them know how they are very important.

Kristen: Well, I could not agree more. I touched on one of the most important things that goes with this life history, and therefore is a legacy of those ancestral grandmothers who were then having these consequences and the shorter intervals. Mom is having another one while the other one is still dependent, and that works because the still dependent ones are covered. They don't die. But it also means these short intervals mean that, "Here I am."

And this is where Sarah Hrdy has been so brilliantly pointing to this since 1999. Her 1999 book, "Mother Nature," the whole last third part of it is all about this thing about human babies.

It is such a striking thing about human babies that developmental psychologists had already been just fascinated with it and talking about it and describing it, this thing about how precociously social human babies are.

You think about it, there's a baby in the room and you walk over and the baby looks to see, and then you go, "Oh, isn't that cute?" And there's all this stuff going on between you and the baby.

If we imagine a chimpanzee baby, well, mom is not going to have another until this one is an independent feeder. Now, what's going on is she's having another one. And so to try and draw her back or somebody back is a matter of survival. And that means such strong selection on this social capacity interactive appetite that is such a big deal in human babies.

Anyway, all of these pieces link back to this feature of the context in which the economic productivity of the females who were nearing the end of their fertile years, they now were contributing to the increased fertility of the younger females. And all the array of correlated features that go with that is just . . .

Kirtly: You've helped us understand why we're hypersocial. Our babies got closer together because it made sense because grandmothers were around and grandmothers were so important in helping our little close-together babies survive. And close-together babies got more socially sophisticated in making people laugh.

Katie: Yeah, I think it really just brings together all the reasons that this period of time post-periods, after the menopause, is so important. It's been really important in our evolution. It's been what's made us human.

And I think sometimes in this day and age, we're sort of losing track that this is this valuable time in life. It's also a time of change. We're social creatures and it means that belonging to a group is important, and we're really tuned into it.

And it seems like in this moment right now, the people that we feel like we're most related to are the folks that you follow on social media. They're right there in the palm of your hand and you see them every day and they're with you in the bathroom and your kitchen and your bedroom. They're familiar in a way that even your best friends are not.

And so while I don't want to minimize the symptoms of perimenopause, I think there's also this thing of living in a world where we're not valuing our elders. And stoking fear of aging is making people a lot of money and why the messages about perimenopause feel so urgent right now.

And so I've loved being able to have this conversation with you, Kristen, that gets us back to thinking about how important a role menopause has played in our evolution as a species, how it's really made us who we are and created all these wonderful things, like our social children and the fact that being part of a group is important. These are all ideas we're going to kind of keep coming back to as we finish working our way through the "7 Domains of Women's Health."

So Kristen, I want to say thank you for sharing your work with us. Your work has absolutely made the whole world smarter.

Kirtly: Oh, it's made my career work. So your work made my career, as someone who cares for menopausal and perimenopausal women, mean so much more because now I have a reason to live. And personally I'm out there, a woman of a certain age, my career. So thank you, Kristen.

Katie: Your work has been a game changer. Thank you for this so much.

Kirtly: Women don't have to be biological mothers to provide wisdom and kindness and leadership to families and communities. We can grandmother them all. So thank you.

Katie: Thank you for being part of our world and for joining us in this perimenopause journey. You can follow the "7 Domains of Women's Health" wherever you get your podcasts, and you can always find us at womens7.com.