Are Human Beings Alike Or Different? The Evidence Is In, But It`s Hard To Talk About

The human sciences are in a paradoxical situation.
Vast quantities of

new data are pouring in,
particularly from the

exponential improvements in genome sequencing
. Yet
theorizing about what the new data imply has seldom been
more career-threatening—as the fates of

James Watson

Larry Summers

Perhaps not surprisingly, the May 10, scientific
conference on "Evolution, Culture, and Human
at UC Irvine, which brought together
leading theorists for a day of presentations centered
around the debate over human uniformity vs. human
biodiversity, flew under the radar. It needed only a
single normal-sized classroom.

Still, the few dozen spectators included an honor
roll of prominent figures in the human sciences.

For example,

Leda Cosmides
, the co-developer of the field of
evolutionary psychology.
Also: John Hawks, the

young anthropologist from the University of Wisconsin,
whose remarkably broad range of expertise, from the
oldest bones to the latest statistical techniques for
genetic analysis, has quickly made him a

star science blogger

Hawks is already a strong prose stylist. If he
continues to improve, he could someday fill the job of
the human sciences` Public Sage—a role for which such
luminaries as

Stephen Jay Gould

Edward O. Wilson

Richard Dawkins
, and

Steven Pinker
have competed.

And in attendance: Gregory Cochran. In evolutionary
theory over the last decade, Cochran has been

the straw that stirs the drink
—as slugger Reggie

described his function
on the tumultuous 1970s
Yankees baseball team. (Here`s the unofficial

Cochran Fan Site

There were four main speakers:

  • Shinobu Kitayama
    , director of the Culture and
    Cognition Program at the University of Michigan.

Kitayama discussed the sizable differences in
personality between

Americans and Japanese
. Just as the stereotype would
suggest, Americans are

more independent;

Japanese more interdependent
. Americans like to feel
individually in control of the situation; the Japanese
are happiest when their group is cohesive.

Interestingly, the Japanese on the northernmost
island of Hokkaido generally fall midway between the
Japanese and American norms. Kitayama speculates that
this is related to Hokkaido having been a wilderness
frontier, not settled until the late 19th Century,
rather like the United States.

Bouchard explained that the state of the art in twin
and adoption studies shows that IQ is highly heritable.
Remarkably, the heritability of IQ goes up as we age.
Identical twins who grew up together tend to become more
alike in IQ when they are adults living apart than when
they were children in the same home.

The conference was organized and emceed by UCI

  • Robert Moyzis
    , one of the co-authors of the

    late 2005
    paper "Global
    landscape of recent inferred Darwinian selection for
    Homo sapiens
    [PDF], which listed
    1,800 genes that have been under varying selection
    pressure in


    , or

    East Asia
    over the last 50,000 or so years. This
    shattered the conventional wisdom that Darwinian
    selection had somehow ceased to operate on the human
    species when our ancestors first left Africa. The
    data now suggests what common sense always
    implied—that when humans dispersed out of the
    tropics, the new environments they encountered, such
    as cold weather, led to important degrees of racial

The central argument of the conference turned out to
be between the other two speakers, the prominent

Henry Harpending
of the

University of Utah

John Tooby

UC Santa Barbara
over, in effect, whether diversity
or uniformity best characterizes humanity.

Harpending spoke first on the accumulating evidence
that human evolution has actually accelerated since we
came out of Africa, especially after the invention of
agriculture. This was proposed by Harpending, with
Cochran, Moyzis, Hawks, and Eric T. Wang, in their
important December 2007 paper "Recent
acceleration of human adaptive evolution
", [PDF]
which appeared in the Proceedings of the
National Academy of Sciences

For example, Harpending suggested that the
prehistoric spread of

Indo-European languages
across a huge swath of
Eurasia from India to Ireland might have been made
possible by a beneficial

genetic mutation
for "lactose
This allows many adults in this
region to

drink milk without gastro-intestinal discomfort
. In
the right terrain for dairying, a tribe whose adults can
get much of their nourishment from the milk of cattle or
goats has a big competitive advantage over tribes that
can`t—perhaps allowing the Proto-Indo-European-speaking
milk drinkers to impose their language and spread their
useful gene.

By the way, a "lactose tolerance-centric"
theory of world history was put forward by the

dairy farmer-turned-economist Raymond D.
Crotty in his ambitious but little known 2001 book When Histories Collide: The Development and Impact of Individualistic Capitalism.
(It hasn`t been published in the U.S., but
you can


part of it on

Google Books
. And here is a

brief summary
.) Crotty attributed the medieval rise

property rights and the rule of law
in Northwestern
Europe to deep roots going back to the type of European
agricultural society made possible by the evolution of
lactose tolerance.

In contrast, John Tooby, co-founder of evolutionary
psychology with Leda Cosmides, who is his wife,
countered Harpending`s emphasis on human biodiversity
with their

Gray`s Anatomy Test.

Open that 1918

of medical charts at random, close your eyes,
and poke a drawing. In all likelihood, whatever tiny
anatomical detail you`re touching can be found in
virtually everybody on Earth. (Or at least everybody of
one sex).

Although the parts differ in size from person to
person, the basic human blueprint is extremely uniform
in terms of which parts are used.

This uniformity is what allows sexual reproduction.
Imagine that you want to assemble a working Toyota Camry
from the parts of two other cars, Tooby suggests. You`ll
see that you`d better start with two other Toyota

As cognitive scientist

Steven Pinker wrote
in his 1994 bestseller The Language Instinct,
produced after a sabbatical year spent in
Santa Barbara with Tooby and Cosmides, "To a
scientist interested in how complex biological systems
work, differences between individuals are so boring!"

Well, that`s one way of looking at it …

Tooby also suggested that human nature is reasonably
uniform in many behavioral areas as well. For instance,
in virtually every society currently in existence,
incest within the nuclear family is unusual and socially

Sigmund Freud famously theorized that humans
desperately want to commit incest with their nearest and
dearest relatives, and that makes necessary the
convoluted apparatus of

. But Finnish anthropologist

Edvard Westermarck
offered a simpler idea way back
in 1891: that humans have evolved an instinct to find
incest repugnant because it leads to birth defects. (In
a 2007 paper in Nature, "The
Architecture of Human Kin Detection
," [
Tooby, Cosmides, and Debra Lieberman offer what they
believe are the two rules for recognizing
siblings—seeing your sibling being nursed by your
mother, or being raised together–that make
Westermarck`s instinct feasible.)

So who is right? Is the human race uniform or

Well, they`re both right. It all depends upon what
you`re interested in at the moment.

That`s usually how it goes—the things that

interest us the most
, that get us most worked up,
are those that are on the knife edge, that look
different when viewed from different angles.

Let`s consider a similar question that`s remote
enough that we can think about without political biases
getting in the way: Is the universe empty or full?

Outer space is famously empty. You can`t get much
emptier than space. By one account, the universe is

as dense as


And yet, outer space is also famously full of "billions
and billions
" of stars, as Johnny Carson used to
say when parodying astronomer Carl Sagan. In 2003, a
team of Australian astronomers estimated that there are

70 sextillion stars
in the known universe. That`s
70,000,000,000,000,000,000,000 stars.

Now, it`s perfectly reasonable to conceive of the
universe both ways, depending upon what you need to
think about at the time. The incredible emptiness of
space is terribly important to understand if you are,
say, contemplating an interstellar voyage. Nevertheless,
to be frank, once you grasp that fact, it gets kind of
boring to think about. So,

spend more time thinking about the tiny
fraction of space that isn`t empty, those 70 sextillion

Similarly, the Wikipedia article on

Human Genetic Variation
reports DATE, "Two
random humans are expected to differ at approximately 1
in 1000


Well, that`s not a very big number.

But Wikipedia goes on to say, "However, with a
genome of approximate 3 billion nucleotides, on average
two humans differ at approximately 3 million nucleotides

Well, three million is a pretty big number. (It`s not
as big as 70 sextillion, but still …)

So, now we can see why, no matter what Pinker says,
the African-American 7`-1" basketball player
Shaquille O`Neal
and the Lebanese-Colombian


seem interestingly different.

Of course, probably they would not at all be very
different at all compared to space aliens possibly
living on a planet going around one of those 70
sextillion stars.

And if those aliens showed up in hostile

flying saucers

conquer the human race
, no doubt Shaq and Shakira
and everybody else would team up to fight them off.

Ronald Reagan
said exactly this to the United
Nations back in 1987:

"I occasionally think how
quickly our differences worldwide would vanish if we
were facing an alien threat from outside this world."
to the 42d Session of the United Nations General
Assembly in New York, New York

But, we`re not facing space aliens. So the
differences between humans are interesting—and

When it comes to thinking about race,—which is all
about who your relatives are—it`s all, well,


[Steve Sailer (
him) is founder of the Human Biodiversity Institute and

movie critic


The American Conservative
His website

features his daily blog.]