Evolving Our Understanding of Our Skin’s Evolution

Recent Penn State graduate Amy Mook interviews Nina Jablonski about her ground-breaking research into the evolution of skin pigmentation, and the promise of that research to help to heal the damage inflicted over generations through misguided racist constructs perpetuated by the scientific establishment of the past.   

HOST:
Amy Mook, 2020 graduate of Penn State’s Genetics and Developmental Biology program

GUESTS:
Dr. Nina Jablonski, Evan Pugh Professor of Anthropology, Penn State 
Co-director of the Center for Human Evolution and Diversity

Transcript

Copy

Mark Shriver:

From Penn State’s Center for Human Evolution and Diversity, this is Tracking Traits 

Mark: 

Hello and welcome to the third episode of the Tracking Traits podcast. I’m Mark Shriver, co-director of CHED – the Center for Human Evolution and Diversity at Penn State University. 

Nina  Jablonski:

And I’m Nina Jablonski, the other co-director of CHED. Welcome to the podcast. 

Mark:

For today’s episode, Nina here was interviewed about her research on the evolution of skin pigmentation by Amy Mook, a recent graduate of Penn State’s Genetics and Developmental Biology program. Amy actually worked in my lab and is now pursuing a dual Master’s of Science program in Genetic Counseling and Public Health at the University of Michigan.

Nina:

And she was a really wonderful interviewer!

Mark:

Right, Amy interviewed the two of us for our first podcast episode. That was the one about the “origin story” of CHED.

Nina:

Yes. So if you listeners missed that one, you might want to go back and check it out.

Mark:

For sure. But right now, we’re going to hear Amy talking to you Nina, about your journey into the investigation of human skin color – how it evolved over time and what some of the related health factors are – and also the many intense social dimensions around the topic in the broader culture.

Nina:

Yeah, Amy really took me back in time to evaluate all these different stages that I went through as a scientist – and a person – as I gradually got over my own hesitancies about taking on such an emotionally and politically-charged topic.

Mark:

That must have been an interesting conversation.

Nina:

It really was, and then we touched on the fact that right here, right now – at Penn State and across the country, and really all around the world – we still have an awful lot of work to do as scientists to try to overcome past mistakes and misconceptions around skin color and race. And I have to say it’s really encouraging to see so many young people – including scientists – showing such interest in these topics – and sharing that drive to help society make its way to a clearer understanding about race, skin color, and the marvelous diversity of the human species.

Mark:

Well said, Nina. Well said. So, we should get into it.

Nina:

Sure, let’s do it.

 Mark:

Here we have it, listeners – Nina Jablonski being interviewed by Penn State grad Amy Mook about “Evolving Our Understanding of Our Skin’s Evolution.”

MUSICAL INTERLUDE

Amy Mook:

Good morning, Nina. It's so great to have the opportunity to share a bit about your story, and your journey through research. I think that our audience will gain a better perspective as to what it is that you do, and kind of how you got here. 

Nina Jablonski:

Thanks a lot, Amy. It's great to speak with you. I've been doing research on the evolution of human skin and especially human skin color, for over 25 years now. And it's been an amazing journey. I started out doing research on the evolution of skin pigmentation really quite by accident, and I realized very early on that there was really very little that had been done on why human skin had evolved the range of colors that we see in modern people. And I could hardly believe it. When I started studying this, I couldn't believe how little had been done. And I realized that part of the problem was that for decades, after the second world war, there was real hesitancy on the part of scientists worldwide to do research on human diversity, especially human physical diversity, because they were worried that studies of human diversity would be socially and politically divisive. And they were just too sensitive.

So, I looked at this, and I thought, "Well ..." This was back in the early 1990s, I thought, "Well, certainly we can start thinking about this differently now. We have, I think, enough background, enough balance as a world society now to be able to think about human diversity, and look at the reasons why human physical diversity exists.”

So, I started on this trek through human skin pigmentation evolution, really not knowing what would come out. But it's been one of the most fascinating things I've ever undertaken. And over the years, what we've done is help to elucidate the reasons why people have different skin under different regimes of solar radiation. And what has happened in human history as people have moved around. Beginning hundreds, and tens of thousands of years ago, what happened when people moved from the tropics, some of them, into very cloudy, or seasonal, or cold areas with much less solar radiation? 

So, basically a lot of this research has been about telling the simple evolutionary history of this interesting trait. But, of course, skin color has come to mean a lot of things to people. And so, over the years I've realized that telling the story of the history of pigmentation, and it's interpretation by people is just as important as telling the evolutionary story, because people have made a big deal out of skin pigmentation, and they've made a big social difference out of skin pigmentation. So, understanding that history, and conveying it to people has been equally important just telling the human evolutionary story.

Amy Mook:

There are kind of two conversations to have there. We could talk about the evolution itself on a more scientific level, but we could also talk about some of those broader impacts in society, and universally about how we think of it. So, could you just elaborate on how you've seen that conversation develop, and what are some of those impacts of your research that you've had on the field, but also in society as well?

Nina Jablonski:

Well, I think there are two major sort of areas of impact that do relate to one another. The first one is the health impact of skin color, skin pigmentation, because as it turns out many people today live under different solar regimes, and under different lifestyle conditions than our ancestors, even just a few generations ago. And although we think of ourselves as really clever human beings, basically we do a lot of stuff that isn't so healthy for ourselves. Humans, as a species, evolved under the sun, and many of us today live in virtually sunless conditions. We go to school indoors, we work indoors, we drive cars to places, or use public transportation, and so we've lost a lot of our relationship with the out-of-doors. What this means is really interesting, because for people with darkly pigmented skin, when they spend a long time indoors and don't have access, or don't go outside for any length of time, their bodies often are deprived of vitamin D which is produced by the sun impinging on the skin, and producing vitamin D as part of a chemical reaction.

This happens in everyone's skin, but in people with dark skin the process is slowed down because melanin is a beautiful, natural sunscreen. If you live in an environment with a lot of sun, having dark skin with natural sunscreen is great. But if you're a modern person living indoors, and spending most of your time inside, then that extra bit of sunscreen actually prevents you from making vitamin D from sunlight as you walk outside for short periods of time. So, that's one aspect of the health problem. The second aspect is for people with light, or moderately pigmented skin, when they go out-of-doors, often, let's say, in the springtime after they've been shut in all winter, they can't wait to strip their clothes off and get some sun. Oh, it feels so good. And then their skin is super sensitive to burning. In ancestral times this rhythm wouldn't have happened, people would have been outdoors much more regularly, we would've followed the cycle of the seasons.

But instead, we have these weird cycles of sort of bursting outside after a long winter's captivity, and we go outside and do some gardening, or play volleyball, or we go on vacation to some sunny place. And many people get a bad sunburn. We're in this strange situation where our modern habits are conflicting with the skin that evolved over tens of thousands of years. So, talking to people about the implications of skin pigmentation for their health is really important, and is actually a very simple conversation to have. 

Far more complicated is the conversation about what skin pigmentation means, because we know that back in the mid 1700s skin color was used as the primary characteristic for assigning people to different races. And we know that one of the first racial classifications was actually a hierarchical classification, done by the philosopher Emmanuel Kant, who clearly put white people on top, as did many Europeans in their classifications.  

This creates what is a really sort of terribly, badly loaded situation, because when human variation, which is natural and valueless, comes to be assigned with a value, it changes the way people think about one another. Differences in skin color are used to treat people differently, to treat people as less than human, and to enslave people. And this is what we see in the history of the last 400 or so years of humanity is differential treatment according to color, in many cases. 

So, trying to explain the origins of this real and painful history is part of the story that I've sort of taken on, to try to explain to people how this really interesting trait, that has evolved as a result of normal processes over tens and hundreds of thousands of years, in recent history has come to be assigned with this invidious set of values.  And those values, in turn, have dictated the fates of hundreds of millions of people.

Amy Mook:

A lot of people listening to this, when we think about diversity, human skin color is a huge factor in that. And so, how does your research really play a role in that conversation? 

Nina Jablonski:

Well, really what we want to do in the center, in CHED, is help people, help ourselves, to understand complex traits, and how they've evolved. But also to help people talk about these complex traits. So, whether it's skin pigmentation, or the shape of someone's body, or their sexuality, we want to explore the evolutionary origins to the best of our ability, and we want to try to talk about these things because so many of the difficulties we have in society arise from when we get frozen in the headlights, as it were. When we stop talking, because we're afraid of taking offense, we're afraid of saying the wrong things, we're afraid of causing some hurt. And what I have found is that if you can learn how to speak about aspects of human variation with simple, straightforward, and non-pejorative language and talk about it matter-of-factly in an evolutionary framework, this helps to pave the way for really constructive discussions about what this means to us as individuals and our behavior and more broadly in society. So, evolution, in a sense, gives us a way in to these difficult discussions. And I think it is a beautiful way for people to put themselves and our societies in context.

Amy Mook:

We're starting to have more of these conversations around diversity, and as you're saying, these are very difficult conversations to have. So, taking a time machine back a little bit, when you first got into this research when thinking about human skin color and evolution, did you foresee that this is where it would end up being? And how did you kind of get into this topic and run with it?

Nina Jablonski:

What's so funny, Amy, is that I remember way back when I was a graduate student, and I was having to teach my first course in biological anthropology, I would dread the lectures that I had to give on human variation because I was so worried about saying the wrong thing, and causing offense and not using the right terminology. And I was just mortified about oh, what are people going to think? Am I going to say too much, or not enough? So, I now sort of laugh at myself back then, because I realize here I'm doing day in and day out what I absolutely dreaded the idea of doing many decades ago. So, I got into this because I thought it was such an important topic, I realized that there was this enormous hole in research. That there was a lot of new data that pertained to this phenomenon that we could bring to bear that hadn't been brought to bear before. And I thought, "Well, certainly we can begin to talk about this in a more sort of scientific and logical way."

And so, I guess I approached the study of it in a logical way in my own mind, and then thought about talking about it to other people by laying out the history of my own inquiry. And basically you know,  bringing them into my story. When I lecture on the evolution of human skin pigmentation, basically I tell people about how I got into this, how this led to an understanding, and then how this led to bigger discussions. And I really didn't start having these bigger discussions about behavior, and thinking about race and racism and attitudes toward others until the evolutionary program was really very mature. I hesitated for a long time because I didn't feel competent to discuss these ramifications of the research. But then I realized, “Hold on, who else is going to talk about this?” Somebody's got to start talking about this, because it's really important. And if people don't understand the biological basis for this trait, that they have put so much stock in, then we're lost.

If people understand that skin color is a product of evolution, it has no inherent value. It just happened as the result of people dispersing to different places at different times. If they get that, then the whole rest of the discussion is about understanding the missteps, and misapprehensions of history. Understanding the racists who have framed much of our interpretation of human variation. Understanding where science and philosophy have gone wrong in their interpretations, and helping to right those processes, especially through the education of young people, basically saying, "Hey, we got this wrong. And we've got to do something to fix it."

Amy Mook:

I think that you have such a methodical approach to this now, and I think it's also really important to dive deeper into when you were a graduate student, and you did have those hesitations and shied away from these conversations. I think that that's something that a lot of us do. These are difficult conversations as we've been saying. I'm under the assumption that that also translates to your researchers, and scientists, that may also shy away from these topics due to the great sensitivity around them, and noticing that your research is going to be publicized, and having those hesitations of doing the right thing, saying the wrong thing, that sort of thing. So, why were you one of those scientists that didn't shy away from that? And what was that thought process you had in that moment? Obviously it's a scary thing to think about, but you did overcome that. So, how did you do that?

Nina Jablonski:

Well, one of the things that I realized was that in the course of giving lectures on the evolution of skin pigmentation, invariably people would ask me about what this meant for race. And our understanding of human physical diversity and how people got along with one another. And I realized that it was almost an abrogation of my responsibility if I didn't start doing more research, and bringing that conversation into the lectures. And I also recognized that I could talk about this stuff with a voice of a scholar, that I was not the fearful graduate student anymore, that I could use the same scientific tools to understand the history of human intellectual inquiry, and the history of scientific racism. And that I could report these things as clearly and authoritatively as I could report on ultraviolet radiation levels at the earth's surface.

And so I think realizing that I could command at least part of the historical literature as well as the traditional territory of science, gave me confidence that I could talk about this. And I know that many people have found it helpful when they sit in one of my lectures on the evolution of human skin pigmentation, often they'll get the whole story. From sort of the beginning of human evolution until you know, modern civil rights demonstrations in the United States and South Africa in the mid-20th century. Basically, how a trait that evolved in a natural, and really quite beautiful and understandable way over hundreds of thousands of years, was misconstrued. How that mis-construal was perpetrated and spread throughout much of the Western intellectual world, and how that came to affect how we treat one another today. I think telling the whole story, sort of in one big sweep, helps people grasp what's going on today in society.

MUSICAL INTERLUDE

Amy Mook:

Thinking about youth, and youth education around these topics, how do we start having these conversations? As you’re saying, it was something that was misconstrued and spread, and now it's how we treat each other. And once you pull those layers away it becomes a much more simple conversation. So, how do we involve youth in this conversation? How do we educate them best on these topics?

Nina Jablonski:

Well, many years ago, when I was talking to my colleague, Henry Louis Gates Jr., at Harvard, you know he said, "We've really got to talk to kids about this stuff." And I realized that he was, of course, absolutely right. It's one thing to talk to university students, or to adults, about the origins of racist attitudes, and misconceptions about skin color, but what we realized is that in many cases adults have already formed their ideas. And trying to get them out of their old patterns of thinking is hard. We know today that there's a lot of training in combating implicit bias. And that this is now really common in many workplaces. But wouldn't it be better if we could simply start talking to kids when they're younger, before those biases have really taken hold?

And what we realized was that if we could start talking to kids about the evolution of skin pigmentation, in very straightforward terms, when they were quite young, like early middle schoolers, that we could actually introduce the understanding of the science. And also introduce them to the fact that this had actually been taken by some scientists and philosophers hundreds of years ago as being something that indicated whether people were sort of better, or more moral, or more capable of civilized behavior than others. When they see this, when they recognize the nonsense of it, they basically say, "Well, why did we pay attention to them?" In other words, they can see the full story. They can understand the bare bones of what's going on, and they can see the fallacies that have really plagued humanity now for hundreds of years.

In the curricula that we've developed so far, in the roll-outs of the curricula, what we've seen is kids having pretty much an immediate reaction to this. Like, “oh, yeah. I completely get it, I completely understand how skin color evolved, and I totally get that people really got it badly wrong.” And that this was something that we should never have placed any value in. Skin color's just an evolutionary trait, like any other. So, I think the real value of science education for kids, is that we can prevent a lot of misunderstandings that cause many, many bigger understandings as people get older in society.

Amy Mook:

Yeah, I love to hear you say that. And I know that many researchers that we're talking with would agree that young scientists, and the youth in general, are our upcoming generation and we do need to be investing time and attention to them. And hopefully facilitating them to become leaders in these conversations. And so, when you are able to sit down with young scientists, or kids in general, what is one piece of advice that you also give them when you're having those conversations?

Nina Jablonski:

I think one of the most important conversations is “you're a scientist, too. You don't have to have this fancy label, and a fancy degree, and a hat on your head with a tassel to be a scientist. You can open your eyes, open your ears, touch, and you can be a scientist by being a good observer.” 

Being confident about one's ability to observe, and to think. I think we tend to make science into this almost cathedral of knowledge. You've got to go through a special door, and do all this special stuff to be able to do this scientific enterprise. But in fact, any human being is a natural scientist. And I want kids to have that confidence in the quality if their own observation, and the quality of their own brains to think about the observations that they're making, because everybody can do this. Everybody can make sense of what they're seeing, and what they're doing.

And they can learn the logic of this process. It really is simple and natural. And so, I want people to feel comfortable about being scientists, even if they grow up to be accountants, or engineers, or gardeners, or whatever. They can all start out being good scientific observers and young scientists.

Amy Mook:

We've been in such a difficult time in our country and there are racist acts, not only at Penn State, but across the country, across the world. And so many things that just are not okay when thinking about human skin color. Penn State itself is even working to create an anti-racist curriculum in order to help address these situations. So, what has been your role in recent events? And what are you involved with to help bring education to these conversations, and help to break down some of these experiences, especially that people of color that have been having?

Nina Jablonski:

Race thinking, and racism in the United States is alive and well. We may like to delude ourselves into thinking that it was something that got taken care of in the 1960s or beyond, but that would be a serious delusion. For decades, during my adult life, we have lived through periods when there have been so-called “race riots” that were covered in the news for a few weeks, and then they basically were relegated to the back pages, and then they disappeared. Conversations and legislation that needed to occur about race-related issues, were relegated to the sidelines. They weren't seen as important to the American democratic experiment, or at least not central to it. 

The good, positive thing to emerge from the death of George Floyd is that these things are now front and center, and they have been front and center for more than a year in American consciousness. And I think they are likely to remain there, because now everyone recognizes the gravity and depth of problem. They recognize that this isn't something that's going to go away with just a little, you know little bit of police training or implicit bias training done here, there, or the other place. That we are dealing with a societal disease that has to be tackled in much the same way we're dealing with COVID, or we've dealt with major diseases in the past. This is a disease of the American spirit, and the American body politic. And we need to deal with it in a very systematic way. 

And so, on the Penn State campus the leadership to their great credit, has taken responsibility for initiating a new university, anti-racist discussion and curriculum. And I know in the Department of Anthropology we've instituted a new course on the anthropology of race and racism basically to bring this into the forefront of students’ and everyone's attention on campus. This is a big issue, and in order for our campus and our country to achieve its full potential we have to deal with it. We have to deal with sort of the evolutionary history, but then the very real psychological manifestations of race thinking on individuals’ individual decision making. When we can begin to get into these conversations, very difficult conversations, we can begin to get to the root of the problem, and begin to solve the problem.

We aren't going to solve these you know hideous problems of racial violence until we recognize where that psychological discomfort and where that hate arises. And that requires some real introspection, some real good education, and some real willingness to have protracted difficult conversations. So, I think we're on the beginning of a long road and I'm excited that we are on that road and that we're not going to deviate, we're not going to go off into the shoulder or the field again. That this is front and center, and this is essential for the continuation of the American experiment.

Amy Mook:

It's so disheartening that it has taken these events to start having these conversations and I myself, am a privileged white woman, and recognize that. And I would just like to hear, if you have any advice for me, and for others listening that may be in a similar situation, how we assist in not deviating from that conversation, as you were saying? Making sure that things are staying on track and that we're having these conversations and making those improvements?

Nina Jablonski:

I think it's really important for everyone, and especially people who have had privileged positions, privileged positions as white people, or people of good financial position, to really converse and enter into discussions and teamwork with people of diverse backgrounds. Not to just talk about it, but to really do it. To build new teams, and to enter into many of those often initially uncomfortable discussions, and relationships themselves. Don't go into a comfortable space. Challenge yourself. Because it is through these gradual challenges, these uncomfortable conversations, that we will all grow and be able to change together. We can't dictate the course of this. We have to create new coalitions, new teams involving people who were once uncomfortable with one another, and then go forward.

I take a lot of my inspiration from the reconciliation process that occurred in South Africa after the end of the apartheid regime. This process of discussions and reconciliation, was very difficult. In fact, often physically and emotionally painful for many people involved. And it wasn't a perfect process, but it involved people getting together and making a real effort. And in many cases, this involves people getting together who may have real enmity against one another, but getting them together in a context where that enmity can be discussed and diffused, because this can really lead to a new level of human communication and understanding, and us going forward in society. 

Again, this isn't something that's going to be fixed in two years or five years. We're talking about a long project. But goodness, it's taken a few hundred years for us to get into this gigantic mess in the United States, where we live in a racialized world that is highly polarized and unequal. We need some long, purposeful conversations with real dedication and real wholeheartedness to get us out of this.

Amy Mook:

Your research does involve a lot of those conversations with so many different people. So, have you had a difference in reactions of your work from white people versus people of color? Have you empowered people of color through your research? What have those conversations been like?

Nina Jablonski:

The conversations I've had, often after I've given lectures in various places around the world, have been some of the most wonderful experiences I've ever had, because I work during my lectures to not use pejorative terminology and to be as straightforward and factual as I can be. And to unfurl the facts of history as clearly and dispassionately as I can. Almost always, not invariably, but the vast majority of the time I have a lot of people, and especially people of color, coming to me and thanking me for information, and thanking me for sort of helping them understand how things came to be. Older individuals. I remember a few older ladies in Richmond, Virginia several years ago, who thanked me for helping them understand why they were vitamin D deprived as children, and why they experienced rickets when they were kids because they didn't have enough vitamin D from being indoors. And they had very dark skin.

And I've had young people in South Africa come down to me at the podium and say, "Why aren't we being taught this every day in our schools? Why are we deprived of this information?" So, you know I feel that people really want straight information. They don't want to be misled, they don't want to hear garbage, or “Just So” stories. They want to understand to the best of their ability what happened, so that they can get on with life, and so they can treat themselves, with respect to health, as best they can, and so that they can treat one another in the way that we did hundreds of thousands of years ago. Humans are not innately racist. We pay attention to differences of all kinds, but we make no inherent value judgements, and that's really, really important to understand.

Amy Mook:

What's next for you and your research? What do you see being the next step?

Nina Jablonski:

Well the basic scientific research, is ongoing because I really, really am interested in basically “how has human skin pigmentation evolved in different places, and at different times?” We now know a lot about the genetic basis of skin pigmentation, and we know that different groups of people in different places have different combinations of pigmentation genes that actually create the pigment that we see. 

So I'm trying to figure out how those different complements of genes worked with environmental factors and with cultural factors to make these, so-called solutions to the problem, work. We know that people living today are the descendants of people who successfully survived in various environments tens of thousands of years ago. So, I'm really trying to figure out “how did we, in different parts of the world, create these different survival equations that led to the present-day success of humans?”

And then, in a completely different vein, I'm really interested in figuring out new ways of educating kids, and the general public, people of all ages, about the evolution of skin pigmentation and human physical diversity for the very reason of trying to sort of unearth the roots of implicit bias, and get people to think about traits that they often wouldn't think about. And get people to think about their own reactions to physical appearance and behavior, because I think whether we're talking about skin pigmentation, or psychological problems, if we understand more of the basis of these things, we can treat one another a whole lot better. I don't expect that we're going to answer these questions, or solve these problems in a generation, or even two generations. But if we indicate that this is the way to go, and this is the way that we have to create educational systems in the future, then I think we'll really be on the right track.

Amy Mook:

I just want to say that I've known the lovely Dr. Nina Jablonski and all her amazing work, and I've heard of it from the sidelines, and now getting to talk to you is really great. And I'm glad to have the opportunity to do so. But others listening to this may not have the opportunity to talk with you face-to-face. Where can our audience find you? Where can they follow this research? I think that this is a conversation that goes well beyond the short podcast, so how can we find you and keep up with what you're doing?

Nina Jablonski:

Well, I'm really easy to find on the Internet. I have a faculty website at Penn State, I have a blog site, and on my blog site I've got all of my media events. Many times I have lectures that are open to the public and many, many times I have recordings of those lectures that are posted, as well as articles for the general public and scientific articles that people can download for free. So, I'm easy to find simply by putting my name into any search engine. That will bring up my websites and you can just take it from there with all of the things that you might want to listen to or read about.

Amy Mook:

We're really grateful that you're always so willing to share about your research and to talk with anybody and everybody about it. I think that's so important for us to be able to follow you and keep up with what's going on, so I appreciate you sharing some of those resources. And also for taking some time to sit down with me today and share a bit more, and allow us to start having those conversations, and maybe spark some interest in our audience. It's been great getting to know you through this podcast and also outside as well. So, thank you for your time today.

Nina Jablonski:

Thanks a lot, Amy. Your questions were great and you were really an engaged interviewer. So, thanks again.

MUSICAL INTERLUDE

Mark Shriver:

Tracking Traits is a production of Penn State’s Center for Human Evolution and Diversity. Our producer, audio engineer and musical theme composer is Cole Hons, and our logo was designed by Michael Tribone of mtribone design. 

If you enjoyed this podcast, please subscribe through your favorite app, and help us reach more people by sharing it with others and rating us on Apple podcasts. 

You can also follow us on social media and learn more about CHED and all of our interviewers and guests at our website, CHED – that’s C H E D dot L A dot P S U dot E D U.