Surprise! Africans are not all the same! (Or why we need diversity in science)

Estimated reading time: 12 mins (2250 words)

(Edit: Link to an article I wrote with my advisor about African skin pigmentation genetics in Genome Biology)

Last week, a research article was published on skin color variation within Africa.

crawford et al
Last week’s article on African skin color in _Science_

READ IT! It is great, well-written, and has amazing figures! I would actually show you some of those figures if I wasn’t terrified of publishers coming after me for copyright infringement (look, I’m trying to finish a Ph.D., here, so I don’t have time to get sued by journal publishers…).

If you don’t have access to these journals, hit up your nearest scholar and ask them for a copy (you can email me!).

And one of the things I really appreciate in this article is that it’s a study on variation in Africa that actually includes African authors from African institutions.

This research is important. That’s why it was picked up by The New York Times and The Atlantic. These articles are all full of people emphasizing that African diversity is an amazing thing that we need to pay attention to!

Read both of those articles too because they are full of quotes that got me feeling some type of way:

“We knew quite a lot about why people have pale skin if they had European ancestry,” said Nicholas G. Crawford, a postdoctoral researcher at the University of Pennsylvania and a co-author of the new study. “But there was very little known about why people have dark skin.”New York Times

Few human traits are more variable, more obvious, and more historically divisive than the color of our skin. And yet, for all its social and scientific importance, we know very little about how our genes influence its pigment. **What we do know comes almost entirely from studying people of European descent. **– Ed Yong via The Atlantic

And there you have it, in bold, the reason I ended up doing a Ph.D. in biological anthropology. I wanted to know more about human biological variation, and I specifically wanted to focus on African diversity.

Why is so much of the research on human trait variation focused on Europeans?

I remember, as an undergraduate, hearing so many times that “Africans have the most genetic diversity” but when it came to looking at trait variation, especially skin color, hair color and hair form, all of a sudden, it was like Africans were just a monolith.

I remember looking for articles on variation in African pigmentation and hair, but all I could find was dozens of articles on how Europeans had all of these ‘diverse’ hair colors and hair types, but Africans could just be described as homogeneously “dark” and their hair was simply “frizzy”. Mind you, these are not articles from the 19th century, these are things that were published from 2000 onwards.

Research saying that “Africans have the most genetic diversity” started to sound a lot like paying lip service without actually believing it.

Looking at the 23andMe genetic testing results, I don’t get the impression that we really respect the idea that “Africans have the most genetic diversity” because these are the reference populations for ancestry in Europeans vs Africans:

European tested populations 23andmeAfrican tested populations 23andMe

I mean, you can tell me if I’ve got “Balkan”, “French & German” or “Finnish” ancestry but the categories for Africa span a third of the continent? That’s a problem. But at least, 23andMe is aware of it…

23andMe ancestry bias

Why does “the public” believe skin color = race?

Based on the titles of the news articles, you’d think the problem is that everyone equates skin color with race.

Headline for NYT
Headline from the New York Times
Headline for Quartz
Headline from Quartz
Headline for Science Alert
Headline from Science Alert
iflscience headline
Headline from IFL Science

From these headlines, I guess the question should be: “Who believes race = skin color?”

Surely the Africans living in Africa and traveling around the continent would have noticed that there is a huge range of variation.

Is this an American/European problem?

Maybe this does indeed have something to do with who, historically, has designed the racial categories.

When Linnaeus first divided humans up into subspecies, skin color was indeed one of the classifiers of the different ‘human races’.

Linnaeus original classification of human ‘variants’

But then again, despite decades of critiques, humans can still be categorized by racialized groups that use skin color as a classifier if we take a peek at the U.S. census categories:

us census categories
Currently on the U.S. census website. And, honestly, looking at the history of the terms, it’s been worse.

Yes, there is certainly a lag time between scientific consensus and public understanding.

But the problem isn’t just with “the public” understanding science, it’s also a problem of the things that have been done in the name of science.

Scientific ‘objectivity’ doesn’t mean the field of human biology gets a pass on diversity.

Whenever I read about scientific racism, I inevitably come across some claim that the great thing about Science is that ‘it’s objective’ and that Science is self-correcting and will eventually uncover The Truth™.

But the problem is the Science isn’t some great force in the universe that just happens. Science is done by scientists, and who those scientists are matters.

Some people genuinely believe that it doesn’t matter who does science as long as it is done correctly The Truth™ will shine through. But that isn’t necessarily true.

No matter how perfect your application of the scientific method is (and, honestly, it rarely is applied perfectly), there is still room for bias.

Just because the process of science is supposed to be objective, doesn’t mean that the hypotheses we think up come from a place of objectivity. Hypotheses are inspired by what we see in the world around us, and that is fundamentally influenced by our perspectives and experiences.

This bias in the hypotheses is especially obvious articles written about sexual selection in skin and hair color and almost everything you find will be about how ‘white skin’ and ‘blond hair’ evolved because these are attractive traits (with little to no evidence as to why that is so, just trust the author on this, obviously, this is a fact).

This bias in hypotheses is undeniable in the fact that when we talk about the (pseudo)scientific work on ‘racial’ differences in intelligence, it is always about the supposed superiority of ‘white’ or ‘European’ people.

There is a very straightforward relationship between those who, historically, have done the science, and who comes out on top when ‘scientists’ ask questions about what traits are attractive or superior.

“Scientific racism is a thing of the past” 

Just because the ‘Annals of Eugenics’ has changed its name to the ‘Annals of Human Genetics’ doesn’t mean we’ve undone centuries of scientific racism.

Just because there have been hundreds of articles and books on scientific racism doesn’t mean we’ve overcome the systematic and structural problems that made it necessary for those articles and books to be written.

Of course, there has been progress. Many scientists have called out racist work and, some, have even dedicated their lives to fighting scientific racism. For most of the biased hypotheses I mentioned above, there have been eloquent responses by other white researchers pointing out the flaws in those works and questioning the validity of hypotheses seeking to prove superiority.

But why do we rely on white scientists to call out other white scientists? Why is science, especially the science of human biological variation, such a ‘white space’?

A few years ago, James Watson clearly felt comfortable enough to say that ‘Africans are less intelligent’. The fact that he didn’t expect the backlash should tell us something about the academic environment he had been living in until that point.

The biggest structural problem in science today is that, in the most ‘prestigious’ societies, institutions and journals (those that have the most power to construct the scientific narrative), it remains overrepresented by certain demographic groups (i.e. white, male, English-speaking), and underrepresented by others.

This influences the kind of science that is done. And it most certainly influences the kind of bad science that slips through the cracks and the kind of biases that are shared behind closed doors.

Diversity isn’t just necessary for fighting ‘scientific racism’, it’s necessary for improving the quality of science.

Even with the best of intentions, scientists can perpetuate stereotypes. In the case of skin color, clearly, there have been a lot of researchers who could not see any the large variation on the darker end of the skin pigmentation spectrum.

This is what I like to refer to as the ’50 shades of Beige’ problem.

This is the reason why Rihanna’s Fenty Beauty line of foundation has done so well – Rihanna recognizes the wide range of skin colors that exist, especially on the darker end of the spectrum.

fenty foundation
Range of shades available for Rihanna’s Fenty Beauty

This is a contrast with companies that manufacture products for all the shades of light skin that exist, but apparently, believe that dark-skinned people are one uniform shade:

YSL foundation

Luckily for scientific work on skin color, we have machines that can measure skin color objectively (reflectance spectrophotometers), so we’ve been able to quantify the great range of diversity that there has been for a while now.

But despite the fact that there have been some researchers who’ve pointed out this diversity for more than a decade, most of the research on skin color (and its genetics) has remained pretty focused on variation found in Western countries:

The first gene identified as affecting human skin color—MC1R—is very diverse in European populations but remarkably similar across African ones. Based on that pattern, says Tishkoff, some geneticists have concluded that the evolutionary pressure for dark skin in Africa is so strong that any genetic variants that altered skin color were ruthlessly weeded out by natural selection. “That’s not true,” says Tishkoff—but it’s what happens when you only study skin color in Western countries. “When you look at this African-centered perspective, there’s a lot of variation.” The Atlantic

We need an African-centered perspective.

This is especially true in my area of study – human hair diversity.

Even with skin color, which we can measure objectively, there’s been a bias in the research and homogenization of African variation, so just imagine for a second what the situation is like for hair variation, which we don’t yet have good methods of measurement for.

I can tell you, the situation is pretty bad.

While people have suggested a number of ways of measuring hair curl, if you look for genetic studies of people’s hair, what you’ll find is that researchers simply categorize people’s hair visually into: ‘straight’, ‘wavy’ or ‘curly’ – and not so surprisingly, these studies focus on European hair variation.

One of my favorite genetic studies on pigmentation and hair form uses a diverse group of Latin Americans, but guess what their categories are for hair curl? ‘Straight’, ‘wavy’, ‘curly’ and ‘frizzy’.

Like I said, even the best of intentions won’t save you from the need for diversity.

The Afro-descendant people in that study cohort probably had a range of hair textures and to reduce that variation to ‘frizzy’ is not just problematic because it’s an insulting term, it also homogenizes a group of diverse people using the hair equivalent of the ’50 shades of Beige’ approach.

I understand the need to use categories if you have a huge amount of data and no good way to measure a trait. But there are options.

And if there had been African or Afro-descendant women involved with the design of the study, I’d think someone would have pointed out that for a few years now, there have been more sophisticated categorizations people with tightly curled hair use to describe their hair types:

curly hair types

Think of all the scientific discoveries we are missing out on because we don’t seek the perspectives of people who can see all of this variation.

Hopefully, in a few years, we can do with hair what we have done for skin and then we can happily read articles telling us about the huge range of diversity in hair within Africa.

Hopefully, in a few years, we won’t be as ‘surprised’ that Africans are not all the same.

Again, I’m very excited about the article that just came out and I will continue to share the hell out of it.

I just wish we weren’t so surprised about African diversity, and I believe this ‘surprise’ is related to the fact that even when Africans and Afro-descendants are the subjects of scientific interest, we are not often enough the ones shaping the work that is being done.

Diversity in other areas of science and other types of diversity

I’ve kept this post centered on the biological anthropology/human biology aspect of science because that’s the discipline I’m familiar with. Of course, there are other areas in science that would benefit from diversity and there are excellent articles and posts about that from other people on e.g. astronomy, mathematics. Some excellent people to follow on this issue include the astrophysicists Chanda Prescod-Weinstein & Jedidah Isler, the biologist Danielle Lee and the podcasts VanguardSTEM and PhDivas. And here’s another article on diversity in STEM just to get you going.

Most of what I’ve talked about here is the way in which black/African opinions would impact science, but it is important to include other underrepresented perspectives as well. These include (but are not limited to) perspectives from: non-English speakers (there’s a whole world out there that’s ignored because people can’t publish in what happened to become the “common” language), non-Western people, people from non-industrialized societies, people who’ve grown up in poverty, LGBTQ people – all of these need to have a voice in science if we truly want to strive for excellence and innovation.

Tina Lasisi
Tina Lasisi
Postdoctoral Researcher in Biological Anthropology

My research interests include human phenotypic variation in hair morphology and skin pigmentation.