Accueil > 07 - Livre Sept : SOCIOLOGIE > 7-12 Sociobiology - A Caricature of Selection Theory

7-12 Sociobiology - A Caricature of Selection Theory

mardi 18 mars 2008, par Robert Paris

Sociobiology-
A Caricature
of Selection Theory

Richard C. Lewontin
Darwin’s

theory of evolution
by natural
selection
was devised by him from
observations
on the domestication
of animals.
The first chapter of the Origin
of Species
is devoted
to a discussion
of selective
breeding
and variation
in
domesticated
animals
and pigeons
in particular.
The human breeder had selected
for particular
traits in reproducing
these domesticated
species, and Darwin
transferred
this notion of selective breeding
from the domain of domestication
to the natural
world.
The analogous
agent to human willful
selection
was
"natural"
selection,
a concept
that occurred
to Darwin after reading Malthus’
essay on population.
Natural
selection would
occur because organisms
struggled
to survive
in a h6stile
nature and only some of the many organisms
born would live
to reproduce.
Darwin’s
theory of evolution
by natural
selection,
then, rests on three
general
principles
which are unchallenged
in their generality.
I)
There is variation
in morphology,
physiology
and behavior
among organisms
belonging
to the same species - the principle
of variation.
2)
There
is a correlation
between
parents
and offspring
in phenotype
so
that relatives
resemble
each other more than do unrelated
individuals
 
the principle
of heredity.
3)
Some phenotypes
leave more offspring
than others - the principle
of
natural
selection.
These three principles
are sufficient
to guarantee
an evolutionary
process.
Provided
there is variation
among objects,
that there is some temporal
stability
in this variation
by some mechanism
of heritabilit_
and that different
sorts of
objects
leave different
numbers of descendants
in time, there must be evolu-
tion•ary change in the composition
of the population.
So, rocks evolve by natural
selection
since they vary in hardness,
split off rocks of equal hardness
and
have different
rates of erosion and t_erefore
of survival.
So too automobiles
evolve by natural
selection
as do soft drink containers.
The system of explana-
tion is so powerful
that it can be applied
to almost any situation
and herein
lies its weakness.
A system of explanation
that can potentially
be used to
explain
any observations
invites caricature
and will be used in a crude and
vulgar
analogical
way by ingeniouspeople.
This is what happened
to the system
of Freudian
psychology
which was so all encompassing
that it has been used to
explain
all of history,
science
and the arts.
So too, the Darwinian
theory has
been vulgarized
for the purpose
of easy explanation
of phenomena.
The latest
episode
in this caricature
of Darwinian
explanation
is the collection
of theories
speculations
and observations
about animal and human behavior
that is called by
its adherents
"Sociobiology".
Sociobiology
is an attempt
to explain
all of anima_ and human behavior
as
the product
of evolution
by natural•selection.
This includes
not only the stereo-
typed individual
and group behavior
of lower organisms,
but all aspects
of human
social and individual
activity
that is within
the normal human
gambit.
E.O.
Wilson’s
"Sociobiology,
The New Synthesis"
explicitly
claims the arts, letters,
music,
ethics, history,
economics,
all the studies of the humanities
and the
social sciences
are to be subsumed under sociobiology
which
will "biologize"
these
disciplines
and give a new scientific
basis both for understanding
human
society
and for directing
it in the future.
An examination
of the structure
of sociobiology
reveals, however,
that it is not a science, but a system of unscientific
specula-
tion.
The first element
in the sociobiological
argument
is to describe
the set of
i
phenotypes
under investigation.
This is done by making very general
and very
superficial
characterizations
of "human nature"
by universalizing
conventional
wisdom.
Thus in Wilson’s
"Sociobiology’ I, we are told that "men would rather
believe
than know" and the people are
extraordinarily
easy to indoctrinate,
indeed
they seek it".
Xenophobia,
domination,
entrepreneurship,
territoriality,
male dominance,
are all said to be universals
of human behavior and then provided
with a biological
explanation.
The facts of history
and of ethnography
do not
support
the universality
of these traits, but history
is almost completely
ignored
by sociobiologists
and exceptions
to these generalizations
in the ethnographic
record are accounted
for by redefinition.
For example, it is stated the exceptions
to the "rule ’’of genocidal
warfare
are only "temporary
aberrations"
or that the
reason all human societies
do not appear
to be territorial
is that "zoologists
have been too narrow in their definition
of territoriality".
In some cases their
claims are directly
contradicted
by the ethnographic
record.
For example, present
day "primitive"
hunter and gatherer
societies
do not engage in genocidal
warfare,
an invention
of the modern
state, but, on the contrary,
engage in a kind of semi-
ritual combat in which very few combatants
are killed or wounded.
In general,
the description
of human behavior
by sociobiologists
is remarkable
for its lack of rigor and sophistication.
There are three confusions
that are
common.
The first is the error of arbitrary
agglomeration.
The totality of human
behavior
is broken up arbitrarily
into units of description
that may or may not
be related
to actual phenotypic
entities
corresponding
to gene action and the
action of selection.
It is now known that the topology of the central nervous
system corresponds
rather poorly to the topology of central nervous
function.
For example,
specific memories
are stored diffusely
rather than being located
at
specific points in the cerebrum.
Even for ordinary
morphology
we are not certain
what the units in evolution
are.
For example,
is the hand a unit in evolution,
or is a single finger,
or a joint in that finger ?
How are we to decide ?
The
difficulty
of dividing
up the description
of behavior
into appropriate
units
is
far greater
than for morphology.
Yet sociobiology
has never discussed
this pro-
blem.
A second error is that of reification,
in which mental
constructs
are mistaken
for real objects.
Are "entrepreneurship"
or "dominance"
or "altruism"
real entities
that evolve in time and have genetic
influences
or are they arbitrary
ways of
describing
human social interactions
that are conditioned
by history
and the
particular
form of society
in which sociobiologists
live ?
Again,
in morphology,
such arbitrary
constructs
exist, as for example,
the chin, which
appears
not to
be an organ in evolution,
but only a way of describing
the relative
positions
of
the alveolar
and dentary
jaw fields.
Third, there is the error of conflation
in which
quite different
phenomena
are confused
because
they are given the same name.
The most striking
example
is
aggression,
a term which is applied
indiscriminately
by sociobiologists
to the
interaction
that occurs between
individuals
when one assaults
another
as the
result of some individual
insult or competition,
and to the political
struggle
between
nation states.
As a result,
there is a facile assignment
of individual
aggression
as the cause of war.
Yet everyone who has ever fought
in a war knows
that most people are there not because
they feel aggressive
toward others,
but
because
they have been conscripted
by the state in the interest
of a political
goal.
Having established
a description
of the human behavioral
phenotype,
the next
task of the sociobiologist
is to ascribe
a genetic basis
or show a genetic
influence
on the characters
described.
It is here that sociobiological
theory is weakest
because
it is here that we demand
some experimental
evidence
and some rigorous
concepts
of quantitative
genetics.
Here sociobiologists
try to have it both ways.
For
some traits it is claimed that "moderate
heritabilities
have been documented",
so providing
a basis for selection.
Other traits, however,
are said to be constant
over the entire human species,
so that the lack of genetic variance
is a proof
that they were fixed in the genes by previous
selection.
It appears
then that
no observation
would contradict
the claim of genetic
determination
of human behavior.
But the understanding
of the basic concepts of quantitative
genetics
seems to be
particularly
low.
The claim of "moderate
heritability"
for a variety
of human
behavioral
traits such as creativity,
motor skills, dominance,
personality
traits,
and so on, is based on the observations
of parent-offspring
correlations
in these
traits.
Yet no separation
of the environments
of parent and offspring
has been
made so that the parent-offspring
correlation
is a total phenotypic
correlation
that cannot be resolved
into a genetic and an environmental
component.
The central
feature of human social organization
is that it is organized
around families and
other groups of relatives
so that genetic relationships
also result in environ-
mental
similarity.
Based on observed parent-offspring
correlations,
the highest
"heritabilities"
in U. S. populations
are for religious
affiliation
and political
party !
The fact is that we do not have a decent heritability
estimate
for any
human behavioral
trait because
no one has succeeded
in separating
the genetic and
environmental
components
of correlation
in human populations.
Sociobiologists
speak vaguely
of i0 per cent of human behavior being governed by genes, yet no
geneticist
would know how to interpret
such a statement.
Does it mean that all
human behavioral
traits have a i0 per cent heritability
(broad or narrow ?) ?
Often sociobiologists
will simply postulate
or assume genes with special and
bizarre
action
in order to account for complex human behaviors.
Thus,
there are
"conformer
genes",
genes for homosexuality,
genes for altruism,
all invented to
make the theory fly.
Clearly,
sociobiology
rests on a very shaky and uncertain
genetic
base.
Having
described
human behavior
in a conventional
way, and having postulated
genes wherever
they are needed,
the sociobiological
theorist now proceeds
to show
how natural
selection
has established
the trait.
Again, no evidence
is offered
for the action of.natural
selection
nor can any be offered because we are entirely
in the realm of past human evolutionary
history.
All that can be offered
are
imaginative
speculations
about how a trait might have conferred
greater
fitness
on its carriers.
This kind of speculation
is easy although it may occasionally
demand
some ingenuity.
Sociobiologists
have been aided in their construction
of
modern Just So Stories
by expanding
the concept of natural
selection.
First, an
attempt
is made to explain
a character
by direct selective
advantage
to the indi-
vidual possessing
the trait.
For example,
a more aggressive
person would get more
food, if food were in short supply, and so survive better and leave more offsprinl
Thus, genes for aggression
and entrepreneurship
would
increase
in frequency.
Other traits seem maladaptive
to the individual
and his or her offspring.
Homo-
sexuality,
for example.
It is asserted
(without evidence)
that homosexuals
have
fewer offspring
than heterosexuals
(obviously
true for complete homosexuals,
but
not necessarily
for those showing mixed behavior).
HOW is it that the genes
for
homosexuality
(invented
with no evidence)
have not disappeared ?
Because
of kin
selection,
the second mode of selection
invoked by sociobiologists.
In kin selection,
an individual’s
genes are spread by sacrificing
its own direct reproductive
fitness
in favor of relatives
who may share the same genes.
The homosexual,
by helping
to raise his or her sibs children may spread his or her genes according
to this
theory.
In particular,
one can sacrifice
his own fitness for eight
first-cousins,
for example,
and come out even.
But what about human behavior
that is directed
toward increasing
the fitnessl
of non-related
persons,
pure altruism ?
This is explained
by the sociobiologists
as a result of selection
for reciprocal
altruism.
If an individual
risks his or
her life for an unrelated
person,
that person will remember
and reciprocate
in
the future,
thus propagating
the genes of both.
Then genes for such reciprocal
behavior
will increase,
as will genes for cheating
in this exchange.
There is no
conceivable
behavior
that could not be explained
by recourse
either to direct
selection,
kin selection
or reciprocal
altruism.
The system is complete.
There is one possibility
of testing
sociobiological
theory quantitatively.
Historical
changes
of major magnitude
have occurred
in the organization
of human
societies
in remarkably
short time periods,
as for example
the rise and fall of
the Muslim
Empire in a few centuries.
But we know how raPid gene frequency
changes
can be and taking account
of the fact that only four human
generations
pass per
century,
it would be hard to account
for these dramatic
historical
changes geneti-
cally.
The sociobiologists
take care of this chink in their armor by inventing
a wholly
new p_inciple,
the multiplier
effect,
which states
that an arbitrarily
small genetic
change in a species may be multiplied
to an arbitrarily
large pheno-
typic effect.
By allowing an arbitrary
but unspecified
multiplier
effect, of
course any observed
phenotypic
change in the species
can be explained
by small
genetic
changes.
Thus the theory is made totally
test-proof.
There is no doubt that human behavior
is, in some sense, the product
of
evolution.
But the human species has reversed
the relationship
of organism
and
environment
that dominates
other species.
For all living organisms,
the environ-
ment is more than an outside
force that impinges
on the organism,
the organism
coping in some passive way.
The organism
and the environment
interpenetrate
each
other so that environment
has a role in making
the organism
and the organism
alters
the environment.
For lower animals,
the effect of the organism
on the environment
is relatively
small, but the human species
is characterized
by being a molder
of
the environment
and therefore
of its own evolution.
The human species
dominates
the environment
and not the reverse.
Therefore
the proper study of human evolu-
tion and a proper understanding
of human social organization
cannot come from a
facile and superficial
analogy with natural
history.
It is up tO those of us whose
domain of study is the exact science Of natural
and artificial
selection
and
population
genetics
to expose the pseudoscientific
attempts to short_circuit
a
proper understanding
of our very complex
species.
Above all, the human
species
must be understood
in its uniquely
human aspects.
DR.
RICHARD
C.
LEWONTIN
 "SOCIOBIOLOGY
 A CARICATURE
OF SELECTION
T HEORY"
ANDREW
LEE :
Is not
part
of the
problem
purely
mathematical
in nature
 ?
The
rate
of _0
or
X
is not
defined.
There
are
very
wide
variety
of models
•with
0
0
n parameters
to fit n points.
RICHARD
C. LEWONTIN :
Yes,
that puts it in a nutshell.
If there is said
to be no phenotypic
variance
(the denominator)
and no genotyplc
variance
(the numerator),
then the problem
of heritability becomes
indeterminate.
Moreover,
the structure of
sociobiological
theory is such that it provides
a few undetermined
parameters
which
allow
the fitting of any arbitrary data.
The old saying
is : "Give
me three parameters
and I
can draw an elephant,
give me four and I’llmake
him walk."
FRED
SCHULTZ
 :
Are the TV networks’ mouthpieces
for the Sociobiologlst
or indirectly influenced
by them
(or are publishing
concerns
mentioned
by you) ?
Not asked
directly at this time - are there any signs of
the development
of a "New
Social Biology"
based
on genetic theory ?
(this question
is
perhaps
related to Gordon
Dickerson’s
question).
RICHARD
C. LEWONTIN :
The media,
including television,
radio, newspapers
and popular magazines
have given a major
play to sociobiology,
especially
just after
Wilson’s
book,
"Sociobiology,
The New
Synthesis",
appeared.
There were
full page
advertisements
in the New
York Times
(unheard
of for a supposedly
scientific work),
major reviews
and articles in many
daily newspapers,
an interview in People magazine,
claims
in Newsweek,
Tim_____e,
etc ....
This makes
part of a wave
of "New
Social
Biology"
or Social Darwinism
which
includes
the theory that criminality is in the
chromosomes,
that social upheaval
is the result of defective wiring in the central nervous
system,
that success
in society is the result of genetically
determined
intelligence,
etc....
The economist
Paul Samuelson
labelled this, and sociobiology
in particular,
as a new Social Darwinism
in his article in Newsweek
three years ago and in the interval
many
economists
have shown
him to be correct in his assessment
by trying seriously
to explain the American
economy
as being based
in the genes.
JAN S, GAVORA :
Your talk makes
us wonder
whether
you are arguing against
Sociobiology
because
you really "underneath"
believe in it ?
My
serious question
is : How
strong a stronghold
sociobiology
has and how much
damage
it is going to make
in Genetics
and Biology ?
In my opinion,
it does not have much
chance
among
people who
breed chickens
or work
experimentally,
but it may
be more dangerous
in other areas.
RICHARD
Co LEWONTIN :
I agree that sociobiologydoes
not, ultimately,
have much
of a future in biology because
it is not really a fruitful scientific theory.
But it has taken hold in the social sciences
and among
those biologists
who work in the
"fuzzy"
areas of evolutionary
theory and animal behavior.
That is why
it is all the
more
important for people like us, breeders,
population
geneticists
and statisticians,
to
insist on a rigorous level of scientific work
consistent
with the soundest
methodological
principles,
and above all, publicly to correct errors where
we
see them.
GORDON
DICKERSON :
You object
to prostitution
of legitimate
genetics
and evolutionary
science
in the pseudo
science
of sociobiology.
This a defensive
or
negative
approach
to protect
our science.
However,
defensive
measures
usually
are less
effective
than
offensive
or positive
ones.
Do you have
suggestions
concerning
positive
approaches
to "understanding
realities
of human
nature,
and incorporating
such
understanding
the planning
of more generally
satisfactory
social
organization ?
RICHARD
C. LEWONTIN :
I freely admit that the struggle against socio-
biology is largely a defensive one.
That is inevitable for us as practitioners of an
exact science.
There will continue to be attempts to use our science superficially tO
support prejudices and to try to erect all-encompassing
theories about the world.
That
is a position we necessarily find ourselves in exactly because we work in a rigorous
experimental and theoretical discipline.
The only positive contribution we can make to building a more satisfactory
social organization is to insist on telling the truth about biology and especially about
the real nature of interactions between genotype and environment inproducing pheno-
type. My own guess is that there is not much in human biology that will constrain
future human societies, but that is only my prejudice.

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