Is Race Biologically Real?

An interview with Ian Tattersall.

Image credit: Dawid A. Iurino. (Image source here.)

Ian Tattersall is a world-renowned paleoanthropologist and a fantastic science-communicator. His awe-inspiring 2012 book Masters of the Planet changed the way that I think about humanity—and about myself too. It’s wonderful to be able to interview a first-rate paleoanthropologist who really knows how to make science come alive.

I hope to interview Tattersall in the future about human origins. But first I wanted to nail down a topic that’s always bugged me: Is race biologically real? We all know that race is a prominent social construct in our world—and informed people all know that racist ideas are nutty/immoral—but many people have no idea what biology says about whether race biologically exists or about what race biologically means.

See below my interview with Dr. Tattersall. I edited the interview to make it more conversational, and I added hyperlinks.

1) What did you argue in your 2011 book Race? that you co-authored with Rob DeSalle?

We argued that the idea that discrete “races” exist just doesn’t hold up.

The notion of “race” intuitively/vaguely seems to describe the physical variety that we see in our crowded multiethnic cities—but close scrutiny shows that discrete “races” don’t exist.

2) What did you and DeSalle argue in your 2018 book Troublesome Science?

We show that a whole array of systematic techniques fail to recognize races as biological units. And that “race”-membership—no matter how you construct it—predicts nothing about any human individual’s cognitive qualities, skill-status, behavioral proclivities, or emotional makeup.

We conclude that race definitions harm our efforts to understand human variation. And that flawed “race”-notions are easily—and destructively—hijacked to serve political/social agendas.

3) What are the biggest misconceptions/confusions that the public has about race? 

That races are real biological units that mean something.

4) Is race real?

No. 

Human geographical variation is real—which simply makes Homo sapiens a pretty standard-issue mammal. But that’s not the same thing as saying that human races are real.

Races are purely social constructs that do not map accurately onto our underlying biology.

5) Is it possible to explain the relevant biology to a layperson in 10 minutes? Or are the relevant concepts too hard to explain in 10 minutes to someone with no biology-background? I watched Richard Lewontin talk about race, and I found it really hard to get my head around the concepts that he was introducing. 

The basics are pretty straightforward. 

Every animal population is variable in its members’ hereditary characteristics. That variation makes each species viable in our ecologically unstable world and makes local populations able to adapt to local circumstances. That variation is what made it possible for our own species to evolve.

This also means that variations will inevitably arise randomly within a species’ local populations. 

And almost all “racial” variation among humans seems to be random because very few variable human traits have any clear adaptive basis. Skin color is an exception—darker skin is advantageous at lower latitudes and disadvantageous at higher latitudes. But most geographical variations among humans don’t seem to be adaptive.

Lewontin put all this together. His greatest contribution to the race-debate was to point out that some 85% of human variation—in a very complex genome—occurs within the populations we often call “races”. Only 15% occurs between local human populations. 

Studies of human genomic variation can tell us a lot about population histories. But only if we abandon notions of race.

6) What does biology say about race?

That human variation is real—if largely random in terms of adaptation. 

But it also says that attempts to cram this variation into “racial” groupings only harms our attempts to understand what underpins that variation.

7) What does Lewontin’s fact—that there’s more variation within local human-populations than there is between local human-populations—imply?

That dividing the human species into “races” will never tell you much about the variation that prompted the dividing in the first place.

8) Is there maybe a useful analogy—from everyday life—that can help people understand this issue regarding variation?

Maybe fact is more useful than analogy here. 

Because there is one crucial thing for people to understand. 100% of the human physical variation that we see is an epiphenomenon of the last 200,000 years—an eyeblink in evolutionary time.

And most of the human physical variation that we see is an epiphenomenon of the last 50,000 years—an even faster evolutionary eyeblink.

9) Do you agree with the American Anthropological Association’s 1998 statement on race? 

Yes.

It basically captures what’s important to understand.

10) The AAA’s 1998 statement asserts that race was “invented during the 18th century to refer to those populations brought together in colonial America”. Does this mean that there are no pre-1700s references to race? 

At least since classical times, Westerners have been aware that people vary geographically.

But usually the differences weren’t perceived as particularly important. 

Two things changed in the eighteenth century. For a start, science gave us the notions of “species”, “varieties”, and “races”.

11) Power/oppression have been around forever and humans have had different appearances forever, so why did it take until the 1700s for race to be invented? 

This is where the second thing comes in: the burgeoning transatlantic slave-trade. Slavery was nothing new, but it had usually been practiced within societies—or imposed on conquered nations.

But as a commerce, it was entirely new in the Western world. It posed new moral/ethical questions, and required rationalization. 

Early rationalizations usually had to do with separate creations, and theologians had to tie themselves in knots. Science was later dragged into the argument as scientists tried to sort out the cultural/physical differences among peoples around the world that the Age of Discovery was bringing to light—and as those who profited from slavery sought by any means to justify it.

12) In what ways was the racial pie cut differently in the past?

Since classical times people seem generally to have thought in terms of between three and five major kinds of people, broadly corresponding to the Old World’s main continental areas. 

Closer examination showed that this was a clear distortion, because populations tend to grade into each other. And people who tried to sort the problem out by other ways of pie-slicing rapidly became bogged-down in a morass of sub-races, mini-races, micro-races, and so forth. Clearly, pie-slicing was not the answer to understanding human variation.

13) What do “clades” have to do with the discussion about race?

Clades are discrete groups of organisms that descend from the same unique common ancestor. Intraspecies relationships are reticulate, so this term isn’t inappropriate below the species-level.

14) My mistake. What do “clines” have to do with the discussion about race?

My late colleague Frank Livingstone was famous for his dictum that “There are no races, only clines”—a cline is a continuous gradation from one state to another. Which is, indeed, what we mostly find as long as we stick to individual characteristics. Skin color would superficially appear to be a great example of a cline—beware, though, because darker/lighter skin-tones can be achieved by a variety of different genetic pathways.

15) When you refer to “race”, isn’t it crucial to distinguish the nutty ideas about race from the incorrect—but at least scientifically-serious—ideas about local human-populations?

The term “race” can mean almost anything to anyone. That’s another good reason to avoid the term.

16) Did geographical isolation produce all of the physiological group-differences—skin-tone, hair-texture, etc.—that exist within the human-population? 

Yes.

As far as we know, a human population has to be small/isolated for a new genetic variant to become the norm within it. For most of their history, humans were hunter-gatherers, thinly scattered across the landscape and easily isolated by environmental changes. But—of course—local populations would have been equally easily reunited by continuing environmental change.

17) If the human-population truly mixes freely on a global scale, then will physiological group-differences eventually vanish?

In principle, yes.

18) When did geographical isolation commerce? When did these physiological group-differences emerge? How many years (of geographical isolation) did it take for them to emerge? 

As I said earlier, our species emerged in Africa around 200,000 years ago, and 100% of the variation in our species emerged since then—a great deal of it in the last 50,000 years or so during which Homo sapiens colonized the entire habitable world. Rapid climatic fluctuation during this period provided ideal conditions for population isolation/recombination to occur and for minor local variations (on the human theme) to emerge.

19) How can we quantify how much geographical isolation has existed throughout humanity’s existence, and is there any chance that geographical isolation will go down to zero in the future? 

That historical figure is virtually impossible to quantify, but it is clear that in recent history the tendency has been toward intermingling rather than isolation. Pandemic restrictions aside, it is clear that cultural barriers will be more important in the future than geographic ones. 

20) How is “genetic variability” defined? 

By the variety of alleles at any particular locus in the genome.

21) If 98% of human-genetics is shared with chimpanzees, then is all human genetic-variation occurring within the 2% that is not “fixed”?

Beware of all this gene-counting. It produces the conclusion that human males are more closely-related to male chimpanzees than to female humans.

22) What is the goal when we “slice the pie”? What makes an explanation of variability—in genetics, or any other domain—a good one? I saw this: “Being of the same race doesn’t necessarily make two people more genetically similar to each other than either of them would be to someone of another race.”

Humans seem to have an innate need to classify things—it’s what our brains do. And it often seems more important to us to classify things than to do so accurately.

The quote is meaningless, by the way, because it wrongly assumes that races exist as discrete entities. 

23) Local human-populations don’t explain human genetic-variability. But what if you argued that not all genes are equal—and therefore local human-populations still explain important differences?

In theory, you could make that argument. But we now know that genes are big-time multitaskers. And you would in any event be hard put to demonstrate that many “racial” human phenotypic-variations are “important”.

24) If you try to use local human-populations to explain X, then how do you delineate the different local human-populations? How many groups do you come up with? 

Conscientious people have tried. Most notably, Stan Garn. He got bogged down in a morass of mini- and micro-races and eventually basically gave up because those populations prove impossible to delineate. If you look closely enough, apparent boundaries simply disappear.

25) If local human-populations are a bad way to explain human genetic-variation, then is there any good way to do it?

Nobody has found a good one yet.

26) Is it true that a forensic scientist can tell someone’s race based on what their skull looks like? If so, what are the implications of this fact? 

As I have tried to make clear, “racial” classifications are misleading. The best a forensic scientist with a skull can do is to make an informed guess as to what local ethnicity the individual belonged to. And to extract some DNA.

27) I once saw human skin-tone variation depicted in a way that shattered colloquial notions. Don’t you run into huge difficulties when you try to “slice the pie” regarding skin-tone?

You do indeed. There’s an infinite gradation of human skin-tones, and many genetic pathways to achieve them.

28) Is skin-tone an entire remarkable gradient?

Actually there are many skin-tone gradients, controlled by different genes.

29) What do you think about this map from this article?

This map is a bit misleading because the averages it shows contain so many exceptions. But it does show general trends.

To quote Frank Livingstone again: “There are no races, only clines.”

30) What strikes you about this image? And what does this image tell us about race?

There is a lot we can learn from our genes about past population-movements, whereas notions of “race” don’t help at all.

31) What do you think about the idea that there’s some way to “slice the pie” based on genetics?

The genetic signal indicates population admixture at least as much as it indicates differentiation. Which makes the pie even harder to slice.