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What nationality has the blackest skin?

How Khoudia Diop Learned To Love Her Dark Skin

Malaka Gharib headshot

She has a skin color that you don’t often see in films, fashion or magazines.

Khoudia Diop, a 19-year-old student and model from Senegal, has a hard time coming up with words to describe it. It’s so dark, she says, it almost seems blue.

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It’s what shot her to the social media stratosphere recently. In August, she posed in a photo campaign with black women of all shades for The Colored Girl, a group that challenges society’s beauty standards.

Diop’s pride in her skin has inspired hundreds of thousands of women to follow her on Instagram, where she posts photos of herself using the hashtags #melaninpoppin and #blackgirlmagic.

For The Colored Girl, that’s the big-picture message. «Little black girls need to see that just by being themselves they are equal,» says Victory Jones, who is one of the group’s founders and now Diop’s manager.

And while her skin tone is unusual in the world of modeling, it’s not in Senegal. Marc Shriver, a professor of anthropology at Pennsylvania State University, has measured skin pigmentation around the world. From his research, he’s found that people from Senegal and the islands of Micronesia have some of the darkest skin tones in the world. That’s typical in countries close the equator, where the dark pigment melanin protects against UV damage from the sun’s rays. He suspected that Diop was from Senegal the moment he saw her picture.

Yet even in Senegal, a land of dark hues, some people aspire for lighter tones. According to a 2002 study in the West African Journal of Medicine, the latest data, 52 to 67 percent of the Senegalese population used skin lightening products on their skin. Family members encouraged Diop to try these creams. People made fun of her coloring. But Diop knew from a young age that her skin made her unique.

Diop was told by cousins to lighten her skin with beauty products, but her sister told her not to because her skin was beautiful. Courtesy of The Colored Girl Inc hide caption

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Courtesy of The Colored Girl Inc

Diop, a college student majoring in business in New York City, modeled in a fashion exhibit in October, and now she’s working with her agency to find ways to bring dark-skinned girls to the catwalk. We talked to her about skin color, beauty norms and her mission to empower girls. This interview has been edited for length and clarity.

When did you first realize that your skin color was special?

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I knew I was a little darker than my friends and family. But I realized that I was really unique when I was in Italy. I was walking on the street and I saw a big mirror. I saw myself among a lot of light-skinned people and I thought, «Wow, my skin is amazing.» Then I understood why people and even modeling scouts stopped me in the street and told me to be a model.

Is that how you got into modeling?

When I was in high school in Paris, some photographers wanted my photos and asked if I was interested in modeling. I wasn’t interested because I wanted to get my education first. I was scared because I didn’t know what I was getting into.

But almost everybody was telling me, why not? So I did it because I wanted to inspire girls. When I was younger I didn’t have any inspiration to like the skin I was in.

Have you met anyone else with your skin tone?

In my family, only my brother has a similar skin color. But in Senegal, the color is common.

Yet some people in Senegal use skin-lightening products.

Everyone there wants to be light. Everyone wants to be whiter. It’s something that they need more education about. They don’t know that being dark is something they don’t need to change.

Did you face any pressure to change your skin color?

Once my cousins in Senegal asked me, «Why do you want to be that dark?» and told me to try skin-lightening creams. I wanted to try it at the time because I felt a little embarrassed being dark, but my sister told me not to, because she said my skin was unique and beautiful.

Did people ever make fun of you?

They called me «darkie» and «god of the night.»

Now that you’re modeling, what kind of comments do you get about your skin?

I hear a lot from women in Africa. And not just from dark-skinned women but from all women struggling because of insecurity. They thank me and tell me that I inspire them. And that makes me feel really, really proud.

The Ancient Origins of Both Light and Dark Skin

A study of diverse people from Africa shows that the genetic story of our skin is more complicated than previously thought.

The researcher Dawit Wolde Meskel takes a skin-reflectance reading.

October 12, 2017

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.

To Sarah Tishkoff, a geneticist at the University of Pennsylvania, that’s a ridiculous state of affairs. “It gives you a very incomplete perspective,” she says.

To redress that imbalance, Tishkoff and her team looked to Africa—the continent where humanity is at its most physically and genetically diverse. They recruited 1,570 volunteers from 10 ethnic groups in Ethiopia, Tanzania, and Botswana, and measured the amount of the dark pigment melanin in the skin of their inner arms. Then the team looked at more than 4 million spots in the volunteers’ genomes where DNA can vary by a single letter, to identify which variations are associated with their skin color.

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They found several, clustered around six specific genes: SLC24A5, MFSD12, DDB1, TMEM138, OCA2 and HERC2. And they showed that these variants collectively account for 29 percent of the variation in skin color in the three countries studied. That’s a big proportion! For comparison, a similar and much bigger study identified hundreds of genes that affect one’s height, but that collectively account for just 16 percent of the variation that you see in large populations.

Tishkoff says that her results complicate the traditional evolutionary story of human skin. In this view, humanity began with dark skin in Africa to protect against the harmful effects of the sun’s ultraviolet radiation. As people migrated to other continents, some groups evolved lighter skin, to more effectively produce vitamin D in areas where sunlight is scarce.

“When you look at this African-centered perspective, there’s a lot of variation.”

But most of the variants that Tishkoff’s team identified, for both light and dark skin, have an ancient African origin. They likely arose in hominids like Homo erectus long before the dawn of our own species, and have coexisted in balance for hundreds and thousands of years. In many cases, the older variant is responsible for lighter skin, not darker. That’s consistent with an idea from Nina Jablonski, an anthropologist from Pennsylvania State University, who thinks that the ancient ancestors of humans—much like other primates—had pale skin. “As our ancestors moved out of the forest and into the savannah, they lost their hair and evolved darker skin,” says Nick Crawford, a researcher in Tishkoff’s lab.

But that wasn’t an all-encompassing change. Different groups of people adapted to their own particular environments, not just around the world, but within Africa, too. “Africa is not some homogenous place where everyone has dark skin,” Tishkoff says. “There’s huge variation.” For example, her team’s measurements showed that the Nilotic peoples in eastern Africa have some of the darkest skin around, while the San of southern Africa have light skin, comparable to some East Asians.

This physical diversity is mirrored in these groups’ genes. 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.”

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For example, a gene called MFSD12 has variants that are linked to darker skin; these are common in dark-skinned people from East Africa, but rare among the lighter-skinned San. MFSD12 also shows how the search for pigmentation genes can reveal new insights about the basic biology of our skin. Two years ago, the gene didn’t even have a name, but it was linked to vitiligo—a condition where people develop white patches on dark skin. By deleting the gene in fish and mice, Tishkoff’s colleagues confirmed that it controls the balance between light and dark pigments.

Another gene called SLC24A5 has a variant that has traditionally been seen as “European,” because it is so starkly associated with lighter skin in Western European populations. But Tishkoff’s team showed that the variant entered the East African gene pool from the Middle East several millennia ago and well before the era of colonization. Today, it is common in Ethiopian and Tanzanian groups, but rare in other areas.

“The study really discredits the idea of a biological construct of race.”

Critically, in East African groups, the variant doesn’t lighten skin color to the same degree that it does in Europeans. It’s a stark reminder that “a person can carry a gene that confers a particular trait in one population and yet not obviously show evidence of that trait themselves,” says Jablonski. “It reminds us that we can’t be cavalier about stating that a particular crime suspect has a particular skin color based on the presence of a single genetic variant in their DNA.”

Sandra Beleza, from the University of Leicester, has done one of the only other genetic studies of skin color to include people of mixed African ancestry. She says that neither her work nor Tishkoff’s have come close to identifying all the genes behind this trait. Further studies, involving other African populations that haven’t been included in genetic studies yet, may help to plug that gap.

While many have used skin color as a means of dividing people, Tishkoff sees the potential for unity and connectedness. “One of the traits that most people would associate with race—skin color—is a terrible classifier,” she says. Even without supposedly “dark” skin, there is a lot of hidden variation. “The study really discredits the idea of a biological construct of race,” she adds. “There are no discrete boundaries between groups that are consistent with biological markers.”

Jedidiah Carlson from the University of Michigan, who has been keeping tabs on how white-supremacist groups misappropriate genetic studies, agrees. “Because visually distinguishable traits common in present-day Europeans, such as light skin color, are also assumed to have arisen within European populations, white supremacists treat these traits as a proxy for superior intelligence,” he says. The history of SLC24A5 reminds us that “light skin pigmentation, and likely other ‘European’ traits, are not unique to Europeans. Human populations have been interbreeding for as long as we have existed as a species.”

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White-supremacist communities “often rally around the demonstrably false claim that Africans are more genetically similar to ancestral hominids than Europeans—and these results turn the tables,” Carlson adds. At several genes that influence skin pigments, “Europeans are actually more likely to be genetically similar to great apes.”

Genetic Study Shows Skin Color Is Only Skin Deep

Skin Color Collage

While many have turned to science to falsely support the notion of a biological construct of race, modern research has demonstrated genetics has little to do with it. Now, as Ed Yong at The Atlantic reports, a large-scale study of skin pigmentation demonstrates that humans with both light and dark skin pigmentation have co-existed for hundreds of thousands of years.

A long-standing assumption about the evolution skin color was that Homo sapiens started out in Africa with darkly pigmented skin, full of melanin to protect from the intense ultraviolet radiation from the sun. As humans migrated out of Africa, it was believed that mutations led to lighter skin that can supposedly regulate vitamin D production in lower sunlight levels. But the new study, published in the journal Science , shows that the evolution of skin color is much more complex.

A team of researchers led by Sarah Tishkoff at the University of Pennsylvania and her postdoctoral fellow Nicholas Crawford measured the skin pigmentation of over 2,000 genetically and ethnically diverse people across Tanzania, Ethiopia and Botswana. They analyzed the genome of nearly 1,600 of those people, which allowed them to identify eight key areas in the DNA associated with skin pigmentation.

As Colin Barras at New Scientist reports, each of these sites had genetic variants associated with paler skin and ones associated with darker skin. Seven genetic variants associated with lighter skin developed at least 270,000 years ago and four more than 900,000 years ago. Considering our species, Homo sapiens, did not evolve until around 200,00 to 300,000 years ago, the discovery suggests that the genes responsible for lighter skin tones were present into the genetic material of our hominin ancestors—hundreds of thousands of years before the first humans walked the Earth.

The study suggests that genes of light and dark skin are more fluid than we once thought. Three of the genes associated with the darkest skin are likely to have evolved from genes for lighter skin tones, Barras reports, meaning that people with the darkest skin tones, like herdsmen who live in the Sahara, may have developed that deep pigmentation in the evolutionarily recent past.

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“People have thought it was just light skin that has been evolving,” Tishkoff tells Barras. “I think dark skin continues to evolve as well.”

The new research «adds unexpected complexity» to the story behind skin color, writes Carl Zimmer at The New York Times. » The dark-skinned people of southern India, Australia and New Guinea, for example, did not independently evolve their color simply because evolution favored it. They inherited the ancestral dark variants Dr. Tishkoff’s team found in Africans,» he writes.

The study also shows a variant of a gene associated with light skin common to Europeans and people form the Middle East called SLC24A5 developed relatively recently, just 29,000 years ago. It has only become widespread in the last several thousand years, even flowing back into Africa during waves of Middle Eastern migration.

The study confirms that societal constructions of race are not useful when it comes to genetics. “One of the traits that most people would associate with race—skin color—is a terrible classifier,” Tishkoff tells Yong, pointing out that there is variation even within dark skin. “The study really discredits the idea of a biological construct of race. There are no discrete boundaries between groups that are consistent with biological markers.”

White supremacists often subvert genetic studies to support their own ideas about race. Yong spoke with Jedidiah Carlson, a researcher at the University of Michigan, not associated with this study, who tracks this misappropriation of genetics research. “Because visually distinguishable traits common in present-day Europeans, such as light skin color, are also assumed to have arisen within European populations, white supremacists treat these traits as a proxy for superior intelligence,” he tells Yong.

But as this study shows, the genes for light skin have been there since the beginning. “If you were to shave a chimp, it has light pigmentation,” Tishkoff says in a press release. “So it makes sense that skin color in the ancestors of modern humans could have been relatively light. It is likely that when we lost the hair covering our bodies and moved from forests to the open savannah, we needed darker skin. Mutations influencing both light and dark skin have continued to evolve in humans, even within the past few thousand years.”

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Jason Daley is a Madison, Wisconsin-based writer specializing in natural history, science, travel, and the environment. His work has appeared in Discover, Popular Science, Outside, Men’s Journal, and other magazines.

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