IRA FLATOW: This is Science Friday. I’m Ira Flatow. When we think of ancient hunter-gatherer societies, which some of us do from time to time, there’s this idea that the men were the hunters and the women were the gatherers. But that story might be more complicated. Producer Alexa Lim has more.

ALEXA LIM: Around 9,000 years ago there were all sorts of animals roaming North and South America– mammoths, horses, and even camels. Of course, there were also groups hunting these big animals. A team of researchers working in Peru uncovered the skeleton of a possible female big game hunter. Their findings are published in the journal Science Advances.

So what does this tell us about our understanding of hunter-gatherer groups? My next guest is here to fill us in. Randy Haas is an author on that study, and an assistant professor of anthropology at the University of California Davis. Welcome to Science Friday.

RANDY HAAS: Thanks, Alexa. Thanks for having me.

ALEXA LIM: So in your study, you looked at a 9,000-year-old site in present-day Peru. Can you kind of give us an idea of what that community was like there during that time?

RANDY HAAS: Well, 9,000 years ago in this part of Peru probably would have not been all that different from what we see today, in terms of the environment. The social landscape, however, it was certainly very different. Today, this landscape where the site is found is the home of the Aymara people. The community that’s near the site is called [INAUDIBLE]. And those people who live in [INAUDIBLE] today are agropastoralists.

In the past, it would’ve been very different. People at that time were hunters and gatherers. They didn’t have domesticated products, no agriculture, no domesticated animals.

Instead, they would have been living in small, highly mobile groups that basically moved around the landscape and procured wild resources. And the economy at that time would have been largely focused on hunting big game animals. And the two species of big game that lived in that part of the world were the vicuña, which is the wild ancestor to the alpaca, and the taruca, which is a type of Andean deer.

ALEXA LIM: So you’ve examined the burial site of a female big game hunter, but that wasn’t initially apparent. How did you come to find out that this was a female?

RANDY HAAS: When we first discovered the individual ceremoniously buried in the ground, we realized right away that it was an adult individual. They were laid on their left side. And what was surprising about this individual was that they were interred with a collection of big game hunting tools. And we knew these were big game hunting tools because they included things like projectile points, the kind of stones that go on the ends of spears that are used in hunting animals. And it also included butchering tools and hide processing.

So we knew right away that they were very likely a big game hunter. But we didn’t know at that point that they were a female individual. In fact, we actually shamefully assumed the opposite. We assumed that this individual was probably a male.

And I remember distinctly the conversations around the excavations. And the conversations went something like, oh, he must have been a really great hunter, a really important person in society. Maybe he was a warrior or a chief or something like this. And I remember thinking, OK, maybe that’s possible. I don’t know.

But the real finding came later in the lab when our project bio-archaeologist, Dr. Jim Watson at the University of Arizona, analyzed the skeletal materials more closely. And I remember he came to me one night and said, Randy, you know the hunter burial you guys found? I think he is a she.

I went, oh, really? OK, well, that’s interesting. But he was very cautious because as you may have seen in the imagery, the burial is very poorly preserved. So it was a very tentative identification. But the real clincher came later when I was working with Dr. Glendon Parker, a forensic scientist at the University of California Davis, and he had developed a technique for sex estimation using sex-linked proteins in the dental enamel of individuals.

ALEXA LIM: And was this surprising to you? Or were there other clues that maybe there were other female big game hunters?

RANDY HAAS: So this was very surprising to me. Again, I say somewhat shamefully. It was surprising to me at the time because although it wasn’t off the table that this individual could be a female big game hunter, it just seemed by chance that we happened to stumble upon an early big game hunter that happened to be a female seemed very unlikely.

And this is because we know from hunter-gatherer ethnography, from looking at recent and modern hunter-gatherer populations, that females very rarely are observed to participate in big game hunting. It’s an overwhelmingly male-dominated occupation. But occasionally there’s an occasional female that has been observed hunting big game in hunter-gatherer societies. So on one hand, it didn’t seem totally impossible that we had a female big game hunter on our hands. On the other hand, it seemed somewhat counterintuitive that, by chance, that this the one individual we found with big game hunting tools was female.

So that led us to basically two possible explanations that we just couldn’t really unpack from the burial alone. On one hand, this individual could have been sort of a one-off, a rare instance of a female big game hunter in a world where males dominate that occupation. Or it was hinting at a broader behavioral pattern in which both males and females equally participate in big game hunting.

ALEXA LIM: Do you have any idea which one that might be?

RANDY HAAS: We think we do now. We needed to figure out a way to pack them. The way you’d like to be able to do that is go out and excavate a whole bunch of burials associated with big game hunting tools and count up how many of them are female and how many are male. And that would be the way to do it.

Unfortunately, archaeological science is a slow science. You don’t encounter a discovery like this every day. So what I did at that point was I hit the literature and started looking for any recorded instances of human burials that pre-date 8,000 years ago in the Americas. This is roughly contemporaneous with the burial that we found.

If you look at the raw numbers, the sample size is not enormous. By archaeological standards, it’s a wonderful sample size. By most standards, it’s a rather a small sample size.

But if you look at the counts– and I think it was 11 females and 16 males– that translates to a ratio of approximately 40% female to 60% male. But if you want to know what the possible ratios are that could give rise to that sample– and this is a statistical question– it turns out that anywhere between 30% to 50% female participation in hunting could give us the sample that we see. And that makes it a gender neutral enterprise, or at least nearly so.

ALEXA LIM: That’s not a insignificant number, that’s pretty high.

RANDY HAAS: That’s right. And when you compare it to what we see in the ethnographic record of hunter-gatherers, which is on the order of 1% or less female participation, it’s several orders of magnitude different than what we see in the archaeological record.

ALEXA LIM: The site you are looking at is located at very high altitude, and these hunter-gatherers would have to make some adaptations to that. What did this study reveal about that?

RANDY HAAS: Yeah, one of the models that we were working with in this particular case is a cooperative hunting model. What we were thinking at the time– and I think it’s still on the table, and maybe even finding more support now in light of our recent findings– that one of the ways that people solve the adaptive challenges of the highlands was to work together in the cooperative acquisition of big game. And this finding now suggests that, indeed, everybody in the community was participating in big game hunting.

And today in this very part of the world, Aymara communities regularly get together on an annual basis to do a roundup of these wild vicuña themselves. And everybody participates– men, women, and children. And they do this not to hunt the wild vicuña, they do this to harvest the very precious wool that vicuña provide, and then they sell it for use on the market.

ALEXA LIM: What’s next for your study? Or what questions has this brought up for you?

RANDY HAAS: Yeah, so these surprising findings are pointing us, I think, in some exciting new directions. Now we know we have two ends of the spectrum of occupation in the Americas. We have the early end of the spectrum, where we now seem to think that subsistence labor was not heavily divided. It was gender neutral or nearly so.

And at the other extreme we know that in recent times in the Americas subsistence labor was heavily divided along sex lines. So now the question is, how did we get from point A to point B? So I’m hoping that we can continue to do some of this meta-research, this analysis of the literature in different times and places to see how that process evolved in the Americas.

ALEXA LIM: And there’s this narrative of males as the hunters and females are the gatherers. So how does this idea of female hunters reframe ideas how these hunter-gatherer societies are organized?

RANDY HAAS: It depends on who you talk to. But I think for most anthropologists, we had all accepted the idea that males are hunters and females are gatherers in our species evolutionary past. And this idea, this model, this sort of man-the-hunter model was supported by ethnographic observations, by observations on recent and contemporary hunter-gatherers. And we simply projected that idea back onto the past. And as I said, most people I think readily accepted that idea.

So these findings really encourage us to change that understanding. When we think about it, when we step back and look at it in hindsight, the recent hunter-gatherer past, the ethnography, is really just a drop in the bucket of human history, of several tens of thousands to millions of years of human prehistory. And it now seems that, if these data bear out, and if they extrapolate to other parts of the world– which there’s some reason to think that they might– it now suggests that our species’ evolutionary history was marked by a rather tempered sexual division of labor in which both males and females participated in similar subsistence activities.

ALEXA LIM: And I want to play a clip from a conversation I had with Marin Pilloud, who is an anthropologist at the University of Nevada, Reno. And she studies the role of women in warfare in prehistoric hunter-gatherers in what is now central California.

[AUDIO PLAYBACK]

MARIN PILLOUD: I think it’s just our Western notion of gender roles is so entrenched in everything that we do and see, and it’s really difficult to remove ourselves from our own culture when we try to and look at cultures in the past. It’s hard, when we think men do this and women do this, to see that there are other ways to do things and other ways to behave, and that there is sort of a spectrum to gender and behaviors and gendered roles. And that’s going to change from culture to culture.

[END PLAYBACK]

RANDY HAAS: Yeah, I think that’s true. I think on one hand that there was valid empirical reasons to project these kind of gender constructs onto hunter-gatherer pasts, again, following from ethnographic observations. So I think it was a perfectly reasonable model to start from in that sense. But I do think there is this other layer of sort of sexist Western norms that were also preventing us from potentially recognizing some of the evidence when we were confronted with it.

ALEXA LIM: Well, we’ve run out of time. Thanks so much for joining us.

RANDY HAAS: Yeah, thank you so much for having me.

ALEXA LIM: Randy Haas is an assistant professor in anthropology at the University of California Davis. For Science Friday, I’m Alexa Lim.