Can Men and Women (Baboons) Really Just Be Friends?

FLORA LICHTMAN: This is Science Friday. I’m Flora Lichtman. In honor of Valentine’s Day, we are exploring an age old question, or at least a debate romantic comedies love to explore.

BILLY CRYSTAL: Men and women can’t be friends because the sex part always gets in the way.

MEG RYAN: That’s not true. I have a number of men friends, and there is no sex involved.

BILLY CRYSTAL: No, you don’t.

MEG RYAN: Yes, I do.

BILLY CRYSTAL: No, you don’t.

MEG RYAN: Yes, I do.

FLORA LICHTMAN: That’s, of course, from When Harry Met Sally with Meg Ryan and Billy Crystal, and is perhaps the second most famous scene in the movie.

SPEAKER 4: I’ll have what she’s having.

FLORA LICHTMAN: Anyway, because romantic comedies insist on being romantic, in this movie, the answer is ultimately, no, men and women cannot be friends. But new research adds a wrinkle, at least in the animal kingdom. My next guest is a world authority on a relatively unknown species of baboon, the Kinda baboon. And she found that they append a lot of stereotypes about baboon bonding, primate power dynamics, and how male and female baboons get along. Here to tell us more is Dr. Anna Weyher, founder of the Kasanka Baboon project in Zambia. Welcome to Science Friday.

ANNA WEYHER: Thank you so much for having me.

FLORA LICHTMAN: OK, tell me a little bit about these baboons. Where do they live? What do they look like?

ANNA WEYHER: Yeah, so Kinda baboons, we find them in Democratic Republic of Congo, Angola, and Zambia. And they’re much smaller than the traditional baboon that most people would be familiar with. So they’re about half the size. They’re more slender, and males and females are closer in size.

FLORA LICHTMAN: And you’re one of the first people to study them in the wild. How did that happen?

ANNA WEYHER: Yeah, so I got really lucky. When I was applying to grad school, I ended up starting to work with two professors that had been looking at the genetics of the baboons in Zambia, as there’s three species that occur in Zambia. They used to be considered grouped with a species called Yellow baboons.

But now we know from genetic evidence that they were quite different than originally thought. And so they were looking for someone to start to study these baboons and see if maybe behaviorally, they were different as well.

FLORA LICHTMAN: Yeah, what questions were you asking?

ANNA WEYHER: I had two goals. One was to just study the species that had never been studied. So there’s many studies on baboons, ones that are going back 50 plus years. So there’s a lot of comparative information. So going out and asking similar questions just to see how they compare.

And then more specifically, my main dissertation question and the question that’s evolved over the past 10 plus years is, what are the adult males and adult females doing together over time? Are they spending a lot of time together? Or are females spending a lot of time together?

How do they differ? So in typical baboon that live in large groups, males usually are on the periphery. When they become adults, they leave the group and join another group. Where females remain in the group they were born in, and they inherit the rank of their mother. So they’re very female bonded. Females spend a lot of time together. Males are interacting with females, mostly just during times of mating.

FLORA LICHTMAN: Not friends, is what I’m hearing.

ANNA WEYHER: Yeah, or friends, but mostly in the context of around mating or when infants are really small and vulnerable.

FLORA LICHTMAN: OK.

ANNA WEYHER: And the thought that we were seeing in Kindas from some short pilot studies was that males were interacting with females in all of their reproductive states– so if they had an infant, if they didn’t have an infant, if they were reproductively receptive. And that we saw the males were doing a lot of the friendly behavior towards the females, instead of the females doing it towards them, which is what we see in other baboons.

FLORA LICHTMAN: And not just during mating?

ANNA WEYHER: Yeah, exactly. So high rates in all reproductive states. So in a typical Southern Chacma baboon, a male would be grooming a female and giving her a lot of attention when she’s ready to mate. Or a female would be grooming a male a lot of the time, otherwise, when there’s risk of other males committing infanticide or hurting her infants. So it’s like a protection thing.

FLORA LICHTMAN: It’s really transactional, is what it sounds like.

ANNA WEYHER: Yeah. Yeah. Yeah, in a lot of ways. And so for most of a female’s adult life, she’s the one approaching males. She’s the one grunting and doing affiliative or kind things to try to get the male near her for protection.

FLORA LICHTMAN: Females catering to males, tale as old as time, Anna, tale as old as time.

ANNA WEYHER: And then we might see a switch during the mating, but that drops off significantly. And what I thought I was seeing and what I went out to study and observe in one group over many years is different. Our initial observations actually showing that males are doing a lot more of the maintaining of these friendships, is what we call them, and doing more grooming towards females and females are grooming towards them.

And also more just safe infant interactions, so females letting males hold their infants and groom their infants and males being interested in infants and things like that.

FLORA LICHTMAN: Why do you think the Kinda males are behaving differently than other male baboons? Do you have a theory?

ANNA WEYHER: Yeah, and it’s kind of a suite of characteristics that we think is going on. So as genetic methods have gotten much, much better in the last 20 plus years, we’ve realized that Kindas are probably the basal or the first kind of living baboon that existed. There are six species of baboons, and so those species kind of diverged from that. So this behavior might be the more initial behavior.

FLORA LICHTMAN: Yeah, it’s interesting to me that the older baboon behavior might be this more egalitarian behavior.

ANNA WEYHER: Yeah, and that questions the perception that humans or primates or animals are innately aggressive or want to fight or things like that. There’s actually–

FLORA LICHTMAN: Yes.

ANNA WEYHER: –other strategies. And that, in this Kinda scenario, females are getting a lot more choice. They can be choosier on who they mate with, and it appears that males are spending more time creating longer term bonds with females to hopefully get reproductive mating access, instead of what the traditional baboon model was is that males fight other males to get reproductive mating access.

FLORA LICHTMAN: Yes. I did hear you say in there that it’s a long-term investment to get mating access, which–

ANNA WEYHER: Yeah.

FLORA LICHTMAN: –is actually the plot of When Harry Met Sally, ultimately.

ANNA WEYHER: Right. I was thinking about that actually, as well, that it is the plot really, isn’t it? Like, over time, the nice male might actually reap more rewards than the aggressive one.

FLORA LICHTMAN: And that it actually, at the end of the day, is about mating.

ANNA WEYHER: Yeah, and I think it’s about– the interesting thing too is there’s been studies in grooming and primates. It really is a main social activity. So you think in humans, the most social thing we do is speak with one another and that really maintains bonds. But obviously physical touch is really, really important.

In baboons, they do also make these interesting sounds, but they groom not just to clean. They spend way more time than needed for getting out a bug here or there. It’s really about social connection and reducing cortisol levels. And primates, it shows, that giving reduces those levels as well as getting grooming. So even giving it can make you relax. And so perhaps all that extra grooming that’s going on also reduces the need for so much aggression.

FLORA LICHTMAN: I’m craving some Kinda sounds. Can you do them for me?

ANNA WEYHER: Sure. Yeah, I can do a few. So to ask to either groom or can I groom your infant, there’s a lot of things we call grunting. And it sort of sounds like this, [GRUNTING SOUND]. As an animal approaches and gets closer, and it’s a sound, this grunting, that kind of shows like, I’m coming in nice. I’m coming in nice.

And another kind of– I don’t know if the sound will come through, but we call it a lip smack. And when they’re doing a lot of those behaviors too, they’re smacking their lips. And that’s also just like a comforting, calming sound, if that makes sense, maybe like a cooing.

FLORA LICHTMAN: Not for me, I’ll say. But OK, you do you, Kinda. Is that like a kissy sound?

ANNA WEYHER: Yeah. I mean, it’s like as observers, we don’t really even hear it, I suppose, unless you could get a microphone right in there. They’re just kind of– almost like you are blotting your lipstick.

FLORA LICHTMAN: OK, I love it. I love hearing you do this. Thank you. I feel like I’m there.

I’m so curious what it’s like in the field. I mean, you’ve spent so much time with these baboons. Did you have to gain their trust?

ANNA WEYHER: Yeah, it was a long endeavor. In the area I picked as well, there is some poaching of baboons and just poaching in the area. So baboons, in general, are a little wary. So it took about six months of just trying to follow them every day before they started to kind of calm down and realize that we weren’t there to do harm.

FLORA LICHTMAN: Wow, six months.

ANNA WEYHER: But it really took maybe a year before the trust was earned enough that it felt like it could get really good data and identify individuals. It’s a trust thing.

FLORA LICHTMAN: Do you have to do things to blend in? I mean, are you grooming yourself?

ANNA WEYHER: Yeah, so in the beginning, definitely, I would groom my fleece. Eye contact is kind of a direct threat. So I looked down a lot. Id pretend to eat things that they were eating. And then the trust started to build.

And we don’t interact with them. We don’t try to get too close to them, close enough. But now, we can have several researchers and the group is over 100 individuals, and researchers are kind within that whole thing doing their observations.

FLORA LICHTMAN: What do you still want to know?

ANNA WEYHER: So there are so many things we still want to know. I think one of the interesting things, I think, that we’re just starting to find out is, from the beginning, we got to see males come into the group and see how that happened. But we couldn’t really see what females did when they became adults.

Like, how do they choose their male friend? How do they navigate their social world now that they are being reproductively receptive and can have infants? And so we’ve got to see that a few times.

But now, we have several females that have been born in the group that are becoming adults and are starting to show these patterns. And so that will be really interesting compliment.

FLORA LICHTMAN: Well, I’m always interested in the female perspective, so please come back and tell us about it.

ANNA WEYHER: Yeah, I’d love to.

FLORA LICHTMAN: Thanks, Anna for coming on.

ANNA WEYHER: Thank you. It was such a pleasure.

FLORA LICHTMAN: Dr. Anna Weyer, founder of the Kasanka Baboon Project in Zambia.

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