- Race doesn't matter. In fact, it doesn't
even exist in humans. While that may sound like the idealistic decree of
a minister or rabbi, it's actually the conclusion of an evolutionary and
population biologist at Washington University in St. Louis.
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- Alan R. Templeton, Ph.D., professor of
biology in Arts and Sciences at Washington University, has analyzed DNA
from global human populations that reveal the patterns of human evolution
over the past one million years. He shows that while there is plenty of
genetic variation in humans, most of the variation is individual variation.
While between-population variation exists, it is either too small, which
is a quantitative variation, or it is not the right qualitative type of
variation -- it does not mark historical sublineages of humanity.
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- Using the latest molecular biology techniques,
Templeton has analyzed millions of genetic sequences found in three distinct
types of human DNA and concludes that, in the scientific sense, the world
is colorblind. That is, it should be.
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- "Race is a real cultural, political
and economic concept in society, but it is not a biological concept, and
that unfortunately is what many people wrongfully consider to be the essence
of race in humans -- genetic differences," says Templeton. "Evolutionary
history is the key to understanding race, and new molecular biology techniques
offer so much on recent evolutionary history. I wanted to bring some objectivity
to the topic. This very objective analysis shows the outcome is not even
a close call: There's nothing even like a really distinct subdivision of
humanity."
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- Templeton used the same strategy to try
to identify race in human populations that evolutionary and population
biologists use for non-human species, from salamanders to chimpanzees.
He treated human populations as if they were non-human populations.
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- "I'm not saying these results don't
recognize genetic differences among human populations," he cautions.
"There are differences, but they don't define historical lineages
that have persisted for a long time. The point is, for race to have any
scientific validity and integrity it has to have generality beyond any
one species. If it doesn't, the concept is meaningless."
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- Templeton's paper, "Human Races:
A Genetic and Evolutionary Perspective," is published in the fall
1998 issue of American Anthropologist, an issue almost exclusively devoted
to race. The new editor-in-chief of American Anthropologist is Robert W.
Sussman, Ph.D., professor of anthropology in Arts and Sciences at Washington
University in St. Louis.
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- Sussman and his guest editor for this
issue, Faye Harrison, Ph.D., professor of anthropology at the University
of South Carolina, have enlisted the talents and expertise of anthropologists
across the discipline's four subdivisions -- biological, socio-cultural,
linguistics and archeological anthropology -- plus Templeton and literary
essayist Gerald L. Early, Ph.D., Merle Kling Professor of Modern Letters
in Arts and Sciences at Washington University in St. Louis, to provide
a renewed perspective on race, a topic that historically is linked closely
to anthropology.
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- "The folk concept of race in America
is so ingrained as being biologically based and scientific that it is difficult
to make people see otherwise," says Sussman, a biological anthropologist.
"We live on the one-drop racial division -- if you have one drop of
black or Native American blood, you are considered black or Native American,
but that doesn't cover one's physical characteristics. Templeton's paper
shows that if we were forced to divide people into groups using biological
traits, we'd be in real trouble. Simple divisions are next to impossible
to make scientifically, yet we have developed simplistic ways of dividing
people socially."
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- Single Evolutionary Lineage
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- Templeton analyzed genetic data from
mitochondrial DNA, a form inherited only from the maternal side; Y chromosome
DNA, paternally inherited DNA; and nuclear DNA, inherited from both sexes.
His results showed that 85 percent of genetic variation in the human DNA
was due to individual variation. A mere 15 percent could be traced to what
could be interpreted as "racial" differences.
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- "The 15 percent is well below the
threshold that is used to recognize race in other species," Templeton
says. "In many other large mammalian species, we see rates of differentiation
two or three times that of humans before the lineages are even recognized
as races. Humans are one of the most genetically homogenous species we
know of. There's lots of genetic variation in humanity, but it's basically
at the individual level. The between-population variation is very, very
minor."
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- Among Templeton's conclusions: there
is more genetic similarity between Europeans and sub-Saharan Africans and
between Europeans and Melanesians, inhabitants of islands northeast of
Australia, than there is between Africans and Melanesians. Yet, sub-Saharan
Africans and Melanesians share dark skin, hair texture and cranial-facial
features, traits commonly used to classify people into races. According
to Templeton, this example shows that "racial traits" are grossly
incompatible with overall genetic differences between human populations.
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- "The pattern of overall genetic
differences instead tells us that genetic lineages rapidly spread out to
all of humanity, indicating that human populations have always had a degree
of genetic contact with one another, and thus historically don't show any
distinct evolutionary lineages within humanity," Templeton says. "Rather,
all of humanity is a single long-term evolutionary lineage."
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- Templeton's analysis gives impetus to
the trellis model of evolutionary lineages, as opposed to the candelabra
model, still popular among many anthropologists. The candelabra model generally
holds that humanity first evolved in Africa and then spread out of Africa
into different populations in Europe and Asia. Picture a candelabra, then
imagine three distinct populations emerging from a single stem, each of
them separate genetic entities that have not mixed genes, and thus are
distinct, biological races.
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- The trellis model pictures humanity as
a latticework, each part having a connection with all other parts. It recognizes
that modern humans started in Africa about 100 million years ago, but as
humans spread, they also could, and did, come back into Africa, and genes
were interchanged globally, not so much by individual Don Juans as through
interchanges by adjacent populations.
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- "If you look down at any one part
of a trellis, you see that all parts are interconnected," Templeton
explains. "Similarly, with modern molecular evolutionary techniques,
we can find over time genes in any one local area of humanity that are
shared by all of humanity throughout time. There are no distinct branches,
no distinct lineages. By this modern definition for race, there are no
races in humanity."
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- Out of Africa
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- The candelabra model often is used to
justify the "out of Africa" replacement theory, whereby modern
humans descended from a single African population, expanding out of Africa
and replacing the less advanced Old World humans in Europe, Asia and Africa.
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- Templeton's analysis suggests a less
hostile scenario. "Traits can spread out of Africa to all of humanity
because all of humanity is genetically interconnected," he says. "Spreading
traits doesn't require spreading out and killing off all the earlier people.
They're spread by reproducing with people -- it's make love, not war."
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- Sussman says one of his motivations in
devoting his first issue of American Anthropologist to race was to show
the relevance of anthropology both in the academic world and in our everyday
lives.
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- "Historically, race has been a key
issue in anthropology," says Sussman. "Since about 1910, anthropologists
have been fighting this lack of understanding of what people are really
like, how people have migrated and mixed together.
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- Anthropologists such as Franz Boas, W.E.B.
Dubois, Margaret Mead, Ruth Benedict and Ashley Montagu were in the forefront
of warning people about the dangers of Nazism during the '30s and '40s,
yet the anthropologists' profile on key issues in America has been so low
recently that when President Clinton appointed a committee on race in 1997,
there wasn't a single anthropologist on it.
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- "Anthropology, in some ways, has
become too esoteric. One of my goals with the journal is to show what anthropologists
are doing and how they relate to how we think and how we live."
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