The science of friendship and the value of listening: A Segment, interview transcript

Jonathan Bastian 0:01
Well, it's a pleasure to be joined by Lydia den worth this morning on the program. Thanks for joining us, we appreciate it.

Lydia Denworth 0:07
Hi, Jonathan. It's good to be here.

Jonathan Bastian 0:10
All right, let's jump in here. When we when we think about friendship, and we go way back into time, I presume that the idea of friends might exist between animals and might be Capri human, what do we know in terms of the evolution and the biology of friendship?

Lydia Denworth 0:27
Yes, friendship exists across species. But we did not know that until quite recently. So and, and finding friendship or something like it in other species is one of the things that has shown us recently that that there's so much more to friendship than we thought that it that this fundamental thing and that that's a there's a bigger story. And in people, we thought it was really cultural, a byproduct of language and human civilization. And we've appreciated it for 1000s of years, all the way back to Aristotle and Socrates and, and then philosophers through the years in between, but, but it's only really in the last 20 years or so that we have understood that there's this biology and evolutionary story there.

Jonathan Bastian 1:18
Hmm. Would you say a little bit more about that? I mean, is this something we see in primates? Where does it exist?

Lydia Denworth 1:23
Yeah, so especially in other in non human primates, we see, we see, you know, if you call it friendship or not, I mean, it's a little bit of a of an of a question. Some scientists do call it friendship, some don't, there's lots of concern about, you know, making assumptions about other animals. But I'm gonna go right ahead and call it friendship, especially. So it's especially interesting in nonhuman primates, and monkeys and apes, because they have social lives, many of them that look more like ours. And their brains are quite similar to ours. So what we see in the way they interact can tell us quite a bit about our own history and our own propensities and abilities. And it's also the case. So for instance, there was a lot of research done on baboons in Africa. And they were, they live in an environment that's probably very similar to where, to where humans first, you know, developed and, and so we can kind of look to the baboons in a way as a very simplistic version of what, of what what you stripping away the complex variables of human life, and you're looking at the way these animals interact with so that baboons have friends, rhesus macaques have friends, gorillas, I mean, there are differences in different species. But it's also the case that zebras hang out with the certain animals in the herd more than chance would predict, and not just their relatives. And of course, elephants are famous for their lifelong bonds. Again, not just with family members, but even zebrafish will behave differently in the presence of, of familiar fish and strangers, they freeze when there are, you know, strange fish around and and they're much more relaxed, when they're in the presence of their, quote, friends. So we see this kind of social behavior in all kinds of species. But in humans, of course, it is, it is. It's much more complex. But like I said that finding it in these other species, and especially in the monkeys and apes, I mean, that's where we've learned the most I'd say about our own relationships.

Jonathan Bastian 3:47
It's interesting, because part of me would think you would have maybe your mate or your family, and then anybody else might be competition, or somebody you'd have to deal with. But But I guess what you're saying is that in these in these species, really, there, there is a sense of bonding, and maybe you can talk about what we know about the purpose of these friends? Or or why why, you know, a baboon would choose to keep a friend around.

Lydia Denworth 4:13
Yes, well, it's so it's, I think it's quite fascinating. It's really goes back to thinking about why we and other species live in groups. And the bigger the group, the more complicated the dynamics, but the more you're also able to accomplish in some ways, right? And so, so one of the theories is that our brains as our well as our social world got more complex and we had to keep straight not just our relationship with this person and our relationship with that individual, but their relationship with each other say, or, you know, and keeping track of the relationships and of personalities and of the histories. It requires a bigger brain and so that's the social brain hypothesis that the complexity of your social life is, is an important part of how we got to be as smart as we are as humans. But but also to get to what you sort of specifically, like, what does it get us? Well, it turns out that there are real evolutionary advantages to being good at making and maintaining friends, you could say that there has been a survival of the friendliest.

And that in that is true. So we first saw that in these baboons that researchers were studying in Africa. And they had always thought that dominance hierarchy was probably the most important factor in the fate of these individual animals over time. Right. And, you know, baboons are very hierarchical species. And these but these primatologists, were watching baboons over generations actually have the same troops. And so they were, and they, they, they behave like the scientists are kind of like glorified gossip columnist, they're keeping track of exactly who does what, to whom, when, who held who else is around, but they were keeping track of that for a variety of reasons. And then then something happened that that provoked them into thinking, Wait a minute, maybe there's more to this. So there was a, there was a baboon named Sylvia, who lived in Botswana. And Sylvia was very high up in the hierarchy. But she was also really a pretty nasty piece of work. And she only hung around with her daughter, Sierra. That was her primary grooming partner. And, and then Sierra, unfortunately, was killed by a lion, because that is something that happens to baboons living in Africa. And it's Silvia did something that really surprised the researchers who were watching her but also presumably surprised the other baboons, who were used to her bad behavior. She started trying to make friends, instead of going off and mourning the loss of her daughter and being grumpy in the sort of under it, an acacia tree by herself, she, she changed her behavior, and the scientists wondered what would be in it for her, why would she do that. So what they, what they did was they, they were able to take all that data they had collected about the animal's behavior, and they compared it, they added it up to a number that they essentially equated to how often the baboons were nice to each other. And then they measured that against their reproductive success. So how many babies they had and how healthy those babies how long those babies lived, or whether they lived past a year, and their longevity, how long these baboons lived themselves. And in evolutionary terms, you cannot do better than then reproductive success and longevity. And what they found was that the baboons with the strongest social bonds, lived the longest and had the most reproductive success. And it mattered more than where they were in the dominance hierarchy. And so this was this a hugely important finding, it was in Science Magazine, which is about as prestigious as you can get in science. And and it showed us that exactly what I said that there are real advantages to this. And that, you know, it's not to say that there aren't some successful jerks out there. But if you want, if you want to, you know, the best odds are that if you're good at making friends, and you have strong friends around you, you will do better.

And the reasons are probably I mean, so for baboons, they have to do with protecting against predators, it has to do with finding food, it has to do with, you know, having relationships, people, you can have relationships you can rely on. And in people, it really is kind of the same. I mean, we want our friends there to protect us when the lions come, right. I mean, they're not the actual lions, like you find in Africa, but there are plenty of figurative lions in our lives. And really, in many ways, that is what friends are for, we get all of the joys of friendship, and the rewards that we get from building the relationship keeps us coming back for more. And we do that. So we have built up that relationship so that when we need them, our friends are there. And we are healthier, and we live longer when we have those friends.

Jonathan Bastian 9:30
Yeah, I mean, a lot of your writing has been talking about simply the health benefits of having a strong social network. I mean, and we can think about this in everyday life. I think of just the other day My father was feeling ill I had to go to the hospital he called me he called other people we got him there. We got him back. People that don't have that. I mean, literally can't get the help that they need. But I sense there's a whole lot of other reasons why a strong sense of friends can keep you healthy, long term.

Lydia Denworth 9:58
Yes. So it's it's great. That's the example you give, because taking people to the hospital sort of figures largely in this history of the science of friendship, so for a long time, so what we know is that you live longer if or you are not, we put it the other way, your risk of dying earlier is greater if you are lonely, if you are socially isolated, and if you just straight live alone, all of those things increase your risk by about a quarter to a third of dying earlier. So why would that be and let me just clarify my terms, because there are differences. So loneliness is considered the subjective feeling of a mismatch between the amount of connection you want, and the amount that you have. social isolation is an object of measure of your number of interactions and the size of your social network. And then, of course, living alone is living alone. And early on, when when sociologists and epidemiologists were first beginning to see that there was this connection with longevity, and social integration, they thought that this concept of social support was the explanation, which is exactly what you just mentioned about your dad that if you need to go to the hospital, and you've got someone there to take you, you're more likely to live longer, like that would seem to explain it, right? It's sort of indirect. And that is absolutely true that you do live longer if you have someone around to drive you to the hospital. But baboons don't drive each other to the hospital. And they live longer, too. So clearly, friendship is doing something deeper, right? It's getting into ourselves. And loneliness does too. So a lot of this research, a lot of understanding the benefits of friendship came from first studying loneliness, and looking at the negative. So you can think of it as a continuum, right? loneliness is the one end of your social integration and friendship is the other.

And just in the same ways that loneliness is bad for you, friendship is good for you. So it affects let me just run through the list so that people will really take this seriously. It affects your cardiovascular function, your immune system, so that's your susceptibility, or your resilience to viruses and inflammation. It affects your risk of dementia. So your cognitive health, your risk of depression, your mental health, your stress responses, your sleep responses, you're even the rate at which your cells age, so you biologically age faster if you are chronically lonely than if you are not. And of course, as I've already said, You You're just at risk of dying earlier, if you are lonely. So how is it that friendship, this relationship that exists entirely outside our body can get into the cells under the skin as biologists say, and change how healthy we are? I mean, that's what's so fascinating about this,

Jonathan Bastian 13:04
certainly, and there must be so many different angles to this, for example, we did a program on the importance of human touch, and how that could impact our immune system so much how it was able to get, you know, really, babies that were born bail premature babies out of hospitals faster when they were touched a massage. There's incredible research there. And I just imagine that that's maybe one slice of this, you're touched more, you're held more you're hugged, you are in connection. I mean, connection, as we know, is something that just feels good. I mean, maybe you can add more nuance to this, but it seems there's there's a lot of reasons for this.

Lydia Denworth 13:41
There are a lot of reasons and you're right touches one of them affective touch, we call it that I actually wrote a cover story for Scientific American about this, that you know, that that it's one of the first ways that infant or that newborns learn to be social, because they're getting that caressing touch from their mother usually right away, right and in, it's wiring up their brains in a specific way. But also, all of our senses. I mean, that's what I think is so friendship is about the senses. And actually, during the pandemic, one of the things we were missing, so zoom, the zoom conversation a whole lot better than not having a conversation and not connecting. And it gave us the audio and the video, but we couldn't get touched, we couldn't get smell we couldn't you know, and you don't think of those pieces of your relationship with your friends in the same way, you know, in the same way that you do sort of looking at them. But they were missing and that and that does, there's a cost to that. And so our brains taken through all of our senses, and then we process that.

But we you know, there's still this is actually where the research is continuing to undertake Stand. Scientists call them the mechanisms and pathways that you know, how is it that friendship does these things? I mean, in the immune system, one of the things we know, I said that it that friendship or loneliness can affect how susceptible you are to viruses and inflammation, we know that what happens is that your gene expression, so you know, your body, you come into the world, right with a sort of blueprint in your genes. But we know that a lot depends on what happens to you, then whether those genes are turned on or off. It's like an opinion that is never voiced. If, if they're turned off, right, and the aches, your social experience can affect whether those genes in your immune system that control how your white blood cells respond, it can affect whether they're turned on or off the genes. So obviously, there's even more complicated than that, but that's, that's good enough of a I mean, you can see just how, how specific it can get. Right. And, and you know, stress is another big it's, it does make sense that we know that hanging out with people who you like and feel supported by and who you trust calms you down, right, it lowers your cortisol levels. It releases happier hormones in your body oxytocin and dopamine and endorphins and things like that. And then once stress in your body is a little stress is okay, it's actually can be good for you, but chronic unrelieved stress, of course, we all know is is terrible for you. And loneliness is kind of the equivalent of that it's, it's, it's a chronic, a little it's, it can be a chronic problem, that that that changes the way your body responds to the world, and leaves you less healthy. And actually, I just want to add to this, because I think this is fascinating, and this is quite new. Welcome, the theory is not so new, but that proof is new. So back in the 90s, when people were just beginning to study the physical effects of loneliness, they had a theory that loneliness is like a biological warning signal. It's like hunger or thirst, it's your brain telling you that it's time to connect. And, and that would be the case then that you could say that loneliness is like stress, a little bit is good for you because it is reminding you that to get back out and connect with people, and that if it's unrelieved and chronic, it starts to wear down your your internal your cells and things in your body. And just recently, MIT, ironically, right at the beginning of the pandemic, as we were all going into social isolation. MIT showed that deep in the brain, loneliness looks like hunger. That looks like hunger. Yeah, that hunger pangs, and the feelings of unruly loneliness. look very, very similar. So that is what it is, which I just think is fascinating.

Jonathan Bastian 18:15
It is, yeah. What a way to think about it. And thinking about I think, cortisol and stress. I mean, as you were talking about this, I just I had this feeling of that I think a lot of people can relate to, which is that you see some Dear friends, you sit down together, and there's almost as big exhale of Here we are, right, yeah, we can settle in, we're safe. This is it, we're happy, you know, the stress of the world just kind of just fades away for a little bit. And I find that that is truly so unique among a healthy friendship. Because let's face it, sometimes with family, it's not always that case, right? There's

Lydia Denworth 18:55
a lot of that, or it could be toxic, you know, right, your family. In fact, that is what the word friend, we use it to describe the quality of a relationship. So if you tell me that your brother or your sister or your spouse is your best friend, you're adding a qualitative element to what I know about that relationship. You're telling me about the value added, right? It's not just about being siblings, it's about being great friends. And that tells me that they make you feel happy and good and safe and exactly the way you just described

Jonathan Bastian 33:33
Oh, that's great. Well, I've really enjoyed this conversation. I've been speaking with Lydia den worth journalist, science reporter and author of friendship, the evolution biology and extraordinary power of life's fundamental bond. Thanks so much for the time. We appreciate it.

Lydia Denworth: Thank you, Jonathan.

Jonathan Bastian 19:30
And it's interesting then to start thinking about the difference between a romantic partner and a friend, you know, a wife or a spouse and and a dear friend, how do we begin to disentangle these things when Well, we think that modern day love should include aspects of friendship. So how do you begin to draw that line?

Lydia Denworth 19:50
Well, I think this new science of friendship that that I have been researching and writing about so much and that's in my book is is It does two things, it actually helps to clarify what friendship is. But it also blurs the lines a little bit between these different kinds of relationships. So let me explain what I mean. It clarifies what friendship is, because by studying it across species, we researchers were able to zero in on essential elements of a really quality relationship. These would be the kinds of relationships that have those positive health benefits that I was talking about. And it it requires three things. The relationship is stable and long lasting, it's positive, so it makes you feel good. And it's cooperative. There's a reciprocity to it and helpfulness, right, back and forth. And you need all three of those things. And everything that humans often if you ask people, you know, what's your definition of friendship, they will talk about trust, and loyalty and companionship, all of that can fit into those three things I mentioned, you know this, that they'll stay with the stability, the positiveness and the cooperativeness. So if we say, if we take that as our template for a really good healthy relationship, we can apply that to our spouses and romantic, significant others and to our family members or relatives. So the definition of a friend, simply as someone you're not related to and don't have sex with, is, is limited, right? It's, I think, and it's not, I think we can use this term, this this model of a really good relationship, as a template to guide all of our relationships. Now, let me just not be naive and say, I know that if you live with someone for many, many years, as I have with my husband, or if you have family relationships, there's a lot that gets packed into that there's a lot of decisions you have to make. There's a lot of trade offs and things. It's it's complicated, and there are going to be negative moments. But what is important is that you've got your you're working to preserve the positive, especially in the cooperative part, and that it feels, you know, it feels good, it makes you feel that and I think we can, I also have been for myself, using this science as a way of reminding myself to check my own sort of friendship behavior, you know, we have a tendency to complain how other people treat us without looking at our own behavior, both with our friends and our family. I was joking with someone like I never criticize how my friends load the dishwasher. I criticize my husband and my kids all the time. And do I really need to do that? Maybe not? I don't know.

Jonathan Bastian 22:45
JBL there's so much packed into what's considered a good marriage or good long term relationship. But I think one of the the things that was highlighted in those conversations was that friends allow us to have different needs met, that can't always be met by an intimate partner, which is, I think, is so crucial to to the role that these great friends play in our lives.

Lydia Denworth 25:39
I agree. And I actually it, it looked at the research seems clear that it's healthiest to have a good, strong, romantic relationship, but also to have some friends. And you know, to have to have a little variety there and to have other people that yes, exactly that that you get, you get some needs met in other ways. And you have that it's also Let's face it, it's a place to talk about what the relationship itself exactly, but sometimes that's healthy. And sometimes that is just what we need, and then we can go back to it sort of restored and ready to be more thoughtful.