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Anne Fausto-Sterling
Beyond Difference:
A Biologist's Perspective
Do biologists know things of use to social scientists who study gender? Answering this question
requires a bit of context. During the past few years we have been subjected to a series of blows,
both within the academy and without. The left hook hits us from the media. Lead stories in Time
(August 15, 1994), Newsweek (March 27,1995; June 3, 1996), and The New Republic (Wright,
1994a) (to name but a few) tell us that infidelity and physical desire are both in our genes, that
feminists have hopelessly misled their flock by attacking the first wave of sociobiological claims
about gender and social change, and that differences in brain anatomy might "explain why
women are more intuitive" (Newsweek, 1995, p. 54)....
The popular media's publicity blitz describes the encroachment of biological understandings
on arenas of social behavior previously seen to be the bailiwick of the social sciences. Some
reporters and scientists present these new biological understandings as certain beyond question.
To be sure, according to this view, some gaps in our knowledge remain, but the current wave of
findings has solidified the biological framework on which we hang our understandings of sex
differences. Shouldn't we be happy to have these vexing questions settled once and for all? ...
What tools can I, as a biologist, offer to social scientists wishing to understand the thought
currents of the past few years? What can biology tell us about human sex differences? My
quarrels with many of the arguments about innate human differences and their evolution stem
from understandings of the nature of biological explanation, which differ significantly from those
of writers such as [journalist Robert] Wright, [J. Richard] Udry, and the various Time and
Newsweek authors. The biological work to which I am drawn contains solid theory and detailed
empirical information; using such work as a starting point enables us to build complex,
interesting accounts of behavior....
Why Frogs Jump
I'll start with a seemingly simple question: "Why does a frog jump?" The answer can be given at
several different levels. Within the moment of watching the frog jump, we can suggest a holistic
answer-the frog jumps as part of an ecosystem. It senses a predator nearby and gets out of the
way. A more mechanistic, reductionist approach would focus on the frog's leg muscles: it jumps
because its muscles twitch. Even more specifically, we can reduce the level of explanation to a
discussion of how and why muscles twitch, and we can say it's jumping because two proteins,
actin and myosin, have molecular properties that allow them to contract, something they do in
response to a nerve impulse. Each of these levels of explanation is valid for particular purposes,
but one cannot necessarily substitute for the other....
Focusing on either the contemporary ecosystem or adult muscle function leaves out two
important types of biological analysis and explanation-development (embryological, juvenile, and
adult) and evolution. Both mechanistic and holistic analyses of current behaviors describe what
is. In contrast, examining individual development or species evolution allows us to talk about
how things get to be the way they are....
Evolutionists ... describe events that take place over many generations. An evolutionist
would speak in terms of genetic variation, natural selection, adaptation, and geographic isolation
(to name the most commonly studied mechanisms of evolution)....
Developmental answers respond to the "why" question for individual frogs within a
particular generation, while evolutionists look at changes in gene frequency at the population
level. Suppose I ask why two groups of frogs jump differently. Why, for example, do bullfrogs
jump further than leopard frogs? One can stick with a strictly reductionist explanation. On
average, bullfrogs jump further because they are a lot bigger. And one could reduce that answer
to details about the number of muscle fibers and the comparative biophysics of fibers of different
lengths and thicknesses. But one could add in a second question: why are bullfrogs larger than
leopard frogs? One answer might be development-they are bigger because bullfrogs spend two
years as tadpoles and thus have a much longer growing period than leopard frogs, which
metamorphose in a single growing season. Both explanations are valid, but offer different kinds
of information. One could push matters further, asking why the bullfrog life cycle differs from
that of the leopard frog. An answer here would require data about the evolution of the two
species. When and under what circumstances did they diverge from a common ancestor? What
kind of life cycle did the progenitor species have, i.e., did leopard frogs lose a year of
development or did bullfrogs gain one? And why? Was it due to natural selection, geographical
isolation or genetic drift? Or, does each species even now exhibit developmental plasticity-the
ability to change its life cycle in appropriate environmental circumstances? Answers to these
questions can be acquired empirically. Indeed, solving problems such as these is what many
evolutionary biologists do for a living. It will not do simply to assume the answer.
Many social scientists study gender inequity. Some hope to figure out how to equalize
difference. Others believe that whatever differences they've observed cannot (and perhaps should
not) change. Each of these groups has an underlying and not always articulated theory about the
biological basis of difference; when pressed, they will invoke it to their advantage. But when
dueling social scientists use biological tools to do battle, they do not always think clearly about
the level and type of biological explanation with which they argue.
Thus the first thing social scientists need to think through when they use biology to ask the
difference question is for which level of explanation do they seek an answer. Such a question is
neither innocent nor far-removed from questions of policy. If one finds a sex difference, does it
help to know its immediate physiological cause, or does one really seek a developmental or even
an evolutionary explanation? I assume that in a trivial sense anything we do has an immediate
physiological cause, i.e., if I run from danger, it is not only because I can recognize the cultural
signs of a dangerous situation. It is also because I am physically able to see, hear, and run, in the
same way that a frog can jump because of the actin and myosin in its muscles. But that
knowledge is not particularly interesting if what we want to understand is why I consider a
particular situation to be dangerous in the first place. The answer to such a question depends very
much on why one wants to study difference in the first place. Does one want to learn about it in
order to explain the way things are, or to design policies to change the status quo? I suggest that
currently available types of evolutionary explanations work best in the former case, whereas
developmental understandings are most useful in the latter. As the following discussion makes
plain, understandings at the level of molecular physiology are usually the least useful for a
researcher interested in designing effective social policy.
From Mice to Bats and Beyond
Geneticists look at evolution in a number of different ways. The following discussion comes from
the work of C.H. Waddington (1975). Animal populations consist of individuals with unique
genotypes-the sum of all the genes in a cell. During any particular generation, populations
participate in different kinds of systems. Waddington named one of these "the exploitative
system." Animals, within the limits of their genetic makeup (e.g., mice can't fly from one tree top
to the next; to colonize tree tops they must climb or jump to nearby branches), choose among and
modify possible environments, thus creating an environmental niche. At the same time, animals
in any particular generation develop under particular stresses and strains. Waddington called this
development within a single generation "the epigenetic system." During development, a chance
environmental stress might reveal a developmental potential not ordinarily visible. Suppose, for
example, our hypothetical tree mice hadn't found much food during a particular year. Some
females might go through pregnancy in a condition of near starvation. As a result of that, some
fetuses would die, others would develop normally, and still others might survive but exhibit some
sort of limb defects, say a failure of the skin connecting the limb digits to degenerate during
development as it normally does. Perhaps these abnormalitiesshow up only when a particular
genotype develops in combination with low protein availability. The result: webbed feet. (Such a
scenario is not particularly far-fetched. Rats subjected to prenatal heat stress, for example,
developed longer limbs.) (Siegel, Doyle & Kelley, 1977)
Webbed feet might make mice slow climbers, rendering them more vulnerable to predation
by a passing hawk.... But that disadvantage might be balanced out by an emerging ability-the
webbed feet enable the mouse to glide when jumping from tree to tree, thereby avoiding birds in
the habit of scanning tree trunks for passing mice, and increasing their food options by enabling
them to reach more distant tree tops. The mouse-hawk interactions and the ability to improve
survival by niche extension form part of what Waddington called "the natural selective system."
If the environmental stress of low food availability remained for several generations, mice with
an epigenetic system (i.e., an interaction between environment and genes to produce a new
phenotype) in which development during protein deprivation produced webbed feet, might
survive with higher frequency than that of same genotype developing under high food conditions.
(Note how the same genotype can produce different phenotypes under different developmental
conditions.) Thus the low protein-webbed feet epigenetic system would become more frequent in
future generations. If the selection went on for long enough, these mice might even develop a new
niche, forgoing climbing altogether. Waddington demonstrated that in some cases, new
phenotypes induced by epigenetic stresses stabilize even if the original stress disappears
(Waddington, 1975). Thus a new variety of webbed-footed gliding mouse might emerge and, with
further selection for more efficient gliding, might even evolve into what is called in German a
fledermaus, a flying mouse, or bat. I do not suggest that this is how bats actually evolved; I have
merely created a plausible scenario in order to illustrate the varied biological systems involved in
evolution.
Using Waddington's framework, let's turn to some of the modern-day theorizing about the
evolution of the human psyche. Robert Wright (1994b) champions a new group of academics that
call themselves evolutionary psychologists. In 1992, Barkow, Cosmides and Tooby published
The Adapted Mind, arguably the scholarly founding volume for this emerging field. Their central
premise is that "there is a universal human nature, but that this universality exists primarily at the
level of evolved psychological mechanisms, not of expressed cultural behaviors" (p. 5). They also
postulate that psychological mechanisms evolved as adaptations via natural selection and "that
the evolved structure of the human mind is adapted to the way of life of Pleistocene huntergatherers.... " (p. 5). These academics argue that we can only understand contemporary human
psychology by understanding how the mind evolved.
Some evolutionary psychologists have a lot to say about sex and gender. Recently, David
Buss (1995), a prominent evolutionary psychologist, discussed the natural selective system faced
by primitive humans:
Women face the problem of securing a reliable or replenishable supply of resources to
carry them through pregnancy, and lactation.... especially when food resources were
scarce, that is, during droughts or harsh winters. All people are descendants of a long
and unbroken line of women who successively solved this adaptive challenge; for
example, by preferring mates who show the ability to accrue resources and to share
them. (p. 164)
Buss tells a story of much the same quality as the one I just invented about the evolution of
bats. It has a certain plausibility. Proto-human females must, indeed, have had the challenge of
finding enough nutrition to sustain pregnancy and lactation. But as does my bat tale, Buss's lacks
essential information. Without knowing when the traits of interest became a permanent part of the
human lineage, we can know little about the actual environmental variations, little about the
degree to which nutritional needs, via an epigenetic system, might have sharpened foraging
abilities dormant within some of the genotypes in particular populations, and/or whether systems
of natural selection worked to make food utilization more physiologically efficient. If Buss's
selective scenario played out, perhaps it fueled the development of foraging skills, including the
ability to hold three-dimensional maps in one's mind's eye-returning even after many years, to a
spot which had previously contained a good food source. Certainly Buss can hypothesize that
pregnancy and lactation led females to select males who were good providers, just as I can
hypothesize that it led females to evolve well-developed spatial and memory skills. We might
both be wrong, or right, but without more data and a far more specific hypothesis, we have no
way of knowing.
There are a lot of data about prehistoric human culture and protohominids, and it is
appropriate to use them to devise hypotheses about human evolution. It is not unreasonable to ask
the hypothesis-builders of evolutionary psychology to at least postulate at what point in human or
hominid history they imagine contemporary reproductive behaviors to have first appeared.
"Throughout the Pleistocene" is pretty vague. What is the evidence that it wasn't earlier or later?
What, if any, animal systems provide unnamed models? What were the food and predator stresses
at that moment? Data on these points can be gleaned from the archeological and geological
record. How did humans respond? Biogeographic data can be brought to bear on this point. Was
there a division of labor during this early period of evolution? Or did gender-based divisions of
labor evolve later (Leibowitz, 1978)?
Over how long a period of time did human mating systems evolve? Or are they still
evolving? For example, the earliest humans living in the heart of Africa certainly did not, as Buss
suggests, experience harsh winters. How do the events of interest to evolutionary psychology
relate in time to the expansion and geographical radiation of human populations? What evidence
is there for a long, unbroken line of women? When and where were there genetic bottlenecks during the course of human evolution? How many of them were there? The use of molecular
evidence to trace human evolution has created a great deal of ferment during recent years (Ayala,
1995; Culotta, 1995; Dorit, Akashi & Gilbert, 1995; Gibbons, 1994, 1995, 1996; Hammer, 1995;
Piazza, 1993; Tishkoff et al., 1996). It would be nice if evolutionary psychologists were
specifically to incorporate this new information into their theory building. Which evolutionary
lines or kinds of adaptive behavior were lost or selected for? How much of our current gene pool
do we have because of genetic drift or geographic isolation, how much because of adaptation and
natural selection? Some prior work at least attempts to situate theory-making within a time line
and a set of postulates about which organisms (chimps? bonobos? Australopithecus? Homo
habilis?) evolved modern human mating patterns (Leibowitz, 1978; Tanner, 1981; Fedigan,
1986). Let's engage in current discussions using the best available knowledge base and the most
highly detailed hypotheses available.
Without addressing some of these questions, evaluating hypotheses becomes very difficult.
For example, given how precarious early human existence must have been, isn't it possible that
females realized that no individual male would live long enough or stay healthy enough to
provide over a period of years for his offspring? Isn't it just as likely then that the females who
passed on more genes to the next generation were the ones who hedged their bets and slept with
more than one male? Buss and other evolutionary psychologists engage in what are, in essence,
thought-experiments, but unless much more carefully specified hypotheses are presented, there's
no way to know how the postulated startingpoints relate to the actual starting-points.
The development of scientifically sound theories about the evolution of human behavioral
patterns and their relationship to contemporary behavior could emerge from collaborations
between social scientists, evolutionists, and behavioral biologists. Specifically, those experts in
the social studies of science who have been so bitterly attacked in the current science wars have a
great deal to offer. One model collaboration, developed in the halcyon days before science studies
were taken seriously enough to be attacked, is a paper written by Bruno Latour (Mr. Science
Studies!! See Latour, 1987) and Sharon Strum (Strum, 1987), a primatologist who studies baboon
behavior. Latour and Strum (1986) devised a set of questions aimed at making specific
hypotheses about human evolution. Using their questionnaire, they evaluated the quality of the
theories constructed by both social scientists and biologists. (All failed the test pretty miserably.)
I urge anyone devising theories about evolution and human behavior to use Latour and Strum's
nine questions [Table 1] to measure the scientific quality of their hypotheses. As Latour and
Strum conclude, "the difficulties of tracing human social origins goes beyond the mere
speculative nature of the endeavor. Scientists have not yet come to terms with what makes an account scientific or convincing ... when scientists are unaware of the mythic character and function
of origin accounts ... the coherence of the scientific account suffers" (p. 186).
When, instead of hypothesizing about past evolutionary events, biologists study evolution
in contemporary populations, they collect very particular kinds of data. They monitor food
supply, shelter, rainfall, predator levelssometimes for as long as a decade. At the same time, they
follow individual animals as they mate, raise offspring, and die. They observe the animals, use
DNA fingerprinting to see who fathered the offspring, and measure changes in animal shape, size,
and behavior over several generations (Clutton-Brock, Guinness & Albon, 1982; Davies, 1992).
Evolutionary psychologists also obtain data about contemporary humans and try to reason
backwards from what they find. But because their data come from present-day humans, they need
to attend especially carefully to human epigenetic systems-to what degree specific behaviors
appear in specific environments. Buss writes, "Women's current mate preferences provide a
window for viewing our mating past" (1994, p. 23). Buss conducted surveys in both the United
States and in 37 cultures worldwide, obtaining a total sample size of more than 10,000. Both men
and women rated the importance of 18 different mate characteristics. In all cases women placed a
higher value on men with good financial prospects than vice versa. Buss argues that the present
state of affairs resulted from sexual selection. "Evolution," he writes "has favored women who
prefer men who possess attributes that confer benefits and who dislike men who possess attributes
that impose costs" (p. 21). Buss further argues that the evolution of female preference for
resource-rich males is ancient and not likely to change. Evidence for the latter claim comes from
his observation that the feminist revolution of the 1970's and 1980's did not change this particular
preference.
Table I
Latour and Strum's Nine Questions
1. What are the initial units of evolution (genes? individuals? the family? the species?)
2. Which qualities do the authors think the units possess? (selfishness? self-regulation? harmony?
aggressiveness?)
3. Units with particular qualities enter into relationships with one another. Explicitly, what form
do these relationships take? (exploitative, trade-offs, parasitical, competitive, cooperative?)
4. What time delays are involved in exchanges which take place in the established relationships
between fundamental units? (pre-hominid? hominid? Homo? Homo sapiens? prehistorical? last
week?)
5. What method of measurement can be used to assess answers to questions 1-4? (L & S write, for
example, "It is one thing to state that a baboon behaves as if to improve his reproduction success, but quite another to decide how he can implement this directive when he does not know
who his offspring are" (p. 174).)
6. In what framework of events, is the evolutionary story embedded? L & S note that most evolutionary stories are logical, but usually not specifically historical.
7. What agents or causes are said to play a role within the framework of events? (e.g., a shift from
forest to savannah as a trigger for the evolution of socialness).
8. What is the stated explicit methodology?
9. What explicit political lessons do the authors of a theory draw?
One can look at Buss's data and arguments from several points of view. Social scientists are
more than competent to make judgments about data quality, sampling techniques, cross-cultural
diversity, propriety of chosen statistical evaluations and such; indeed, some have made pointed
criticisms of his research (numerous authors in Behavioral and Brain Sciences, 1989). But evolutionary biologists also have standards for evaluating Buss-like hypotheses. Four, in particular,
have been suggested as essential to the acceptance of conjectures about the evolution of human
reproductive behaviors (Wallen, 1989). First, of course, is there a good fit between the hypothesis
and data? Second, is the evolutionary explanation as good as or better than some proposed
alternative? Third, when using questionnaires to obtain data in support of hypotheses about
reproduction, do observed or independently documented behaviors correlate with answers on the
questionnaire? Fourth, do postulated characters actually relate to reproductive fitness (e.g., does
marrying a wealthier man really increase a woman's chance of producing more and fitter
children)? In the case of Buss's hypothesis that, during human evolution, natural selection favored
women who prefer wealthier men, only the first of the four criteria has been reasonably met.
Evolutionary arguments that meet the highest standards of evolutionary science must always
hold clear the difference between obtaining data to demonstrate the workings of contemporary
selective events, and using contemporary data to devise hypotheses about the past. In his popular
writing, Buss often blurs this distinction. For example, he begins his discussion of human female
preference for males with financial resources by reference to a field study of a bird called the gray
shrike. He cites an elegant experiment in which a field biologist demonstrated that female shrikes
preferred males with larger caches of food. The study shows sexual selection at work in a
contemporary bird population. Buss then moves from his account of shrike behavior, to imagine a
scenario that might have taken place during early human evolution. For female preference for
richer mates to have evolved, he stipulates that prehistoric men would have had to have been able
to accrue and control resources, that different men would have had different resource levels and
that there would have been an advantage to monogamy for the female.... (He never specifies just
when during human evolution this might have been going on, so we cannot use the archeological
record to evaluate his assumptions.) These conditions, he feels, are easily met among humans,
and he reaches back to the contemporary world to grab as an example a Donald Trump or some
Rockefeller or other. He then returns to "women over evolutionary history" and then back again
to contemporary studies of female preference.
What we have, in the end, is a mish-mash of argument in which often very beautifully done
contemporary studies of mating behaviors in animals are thrown in with far less elegant surveys
of contemporary human behavior. The latter are then combined with unsubstantiated but plausible
postulates (like my mouse to bat story) about some unspecified earlier period of human evolution
in which contemporary behavior might have had its origin. I do not argue that it is wrong to think
about the evolution of human behavior. Rather, one must do it using the high standards of the best
studies of behavioral evolution in animals (Fausto-Sterling, 1997; Fausto-Sterling, Gowaty &
Zuk, 1997). And if one is going to build hypotheses about prehistoric evolution, then too, one
must use the standards of the field and the rich, albeit imperfect, information already obtained
from the fossil record.
On Genes and Development
Many biologists, sociologists and psychologists bracket the question of evolution in order to
study contemporary development. Even if Buss, Wright, and others are 100% on target about the
selective forces that led to our current sex/gender systems, broad sweep evolutionary arguments
tell us little about specific mechanisms. In the evolutionary psychologist's scenario, individual females who learned to recognize high-resource males survived and reproduced more frequently
than those who didn't. But what, precisely, were the recognition mechanisms that evolved? Again,
one can imagine a variety of possibilities. There might be something about the physique or
physiognomy of high-resource males that females could spot (just as. .. frog retina cells were selected to tell the difference between birds of prey and potential food). Or, perhaps something a lot
more indirect and potentially transformative of the human or hominid way of life happened.
Perhaps women who talked a lot with other women could gather information through social and
cultural networks; in this scenario, what would have evolved was the ability to gossip and trade
information about nearby males. (Barkow, 1992, also discusses the evolution of gossip.) The
result might be the evolution of elaborate cultural mechanisms, not some built-in hard-wired
unchangeable brain response.
Most psychologists and sociologists are interested in contemporary mechanisms-how an
individual develops throughout his or her life span (Waddington's epigenetic system). What can
biologists tell us about this process, the process of producing a phenotype? Let's first look,
through the lens of the developmental geneticist, at the relationship between genes and
environment.... [G]eneticists study. .. "the norm of reaction." They look at development as it
occurs in different environments.
... Studying norms of reaction reminds us that most of the time there is no such thing as a
fixed genetic trait. Genetic traits can only be defined in a particular environment....
Knowing about norms of reaction highlights the most common fallacy encountered in
discussions about the genetic basis of behavior-the presumption that individuals have constant
environments, and that, in the absence of empirical measures, one can predict for any or all
environments, the phenotype produced by a particular gene. If physical phenotypes are plastic,
isn't it likely that behavioral phenotypes are plastic in spades? ... [I]t makes more sense to think of
the plasticity, rather than the specific behavior, as being under genetic control. In fact, geneticists
studying animals and plants have amassed experimental data showing that plasticity is a trait
under genetic control, and can evolve via natural selection. Among ecologists and quantitative
geneticists, the evolution and genetics of plasticity is a very hot topic right now (for example:
Newman, 1988; Gomulkiewicz & Kirkpatrick, 1992; Scheiner, 1993; Schlichting & Pigliucci,
1994; West-Eberhard, 1989). Yet neither the concepts of the norm of reaction or phenotypic
plasticity have appeared as a serious part of evolutionary theories about human sex differences.
How an individual looks or behaves, then, results from the full panoply of gene expression
evoked in a particular environment. Having the gene is not enough. If it stays silent throughout
the life cycle, its effect is never seen, and we certainly do not express all of the gene sequences
found in our DNA. But even within a carefully defined environment and with (hypothetically)
full knowledge of all interacting genes, a third factor contributes to the outcome-random chemical
fluctuation. Random processes occur in every developmental generation, but they are not part of a
genetically controlled developmental program. Thus they are not directly selected for. Biologists
sometimes refer to these onetime events as "developmental noise."...
Conclusion
The discussions of sex differences that one reads in various settings, from scholarly texts to the
media, frequently slip from one category of biological explanation to another. This slippage
makes it difficult to assess the strengths and limitations of particular knowledge claims. One finds
oneself simultaneously coping with reductionist explanations for behavior (frogs jump because
their muscles twitch) and evolutionary explanations, which address rather different biological
questions and demand different types of proof. To have intelligent discussions and arguments
about the role of biological difference in the genesis of gender difference, we must attend to what
level of explanation is being offered, and to hold those with whom we debate these questions to a
higher standard of explanatory clarity than has hitherto been offered.
Evolutionary explanations of difference often entail elegant theories based on very partial
knowledge of contemporary cultures and on analogies from animals, but without any foundation
in the specific history of human evolution. There are no studies of human evolution comparable
to those on red deer (Clutton-Brock, Guinness & Albon, 1982) or chimpanzees (Goodall, 1986).
And the two species of chimps, for example, have strikingly different mating systems. Who shall
we choose as our model female? Females of the betterknown chimp species have an associated
pattern of hormones and copulation, but the bonobo female has sex constantly with both males
and females, she apparently uses sex not just for reproduction, but as a medium of social
mediation (Parish, 1994; de Waal, 1995). Evolutionary explanations of human sex differences
usually ignore an entire literature on norms of reaction and phenotypic plasticity. Using this
strong and interesting literature in basic genetics and ecology could lead to a very different kind
of story-telling. It is primarily the feminist Darwinists such as Jane Lancaster, Barbara Smuts, and
Patricia Gowaty who have incorporated contextual diversity and polymorphism into their evolutionary accounts of human behavior (Fausto-Sterling, Gowaty & Zuk, 1997).
So, do biologists know things of use to social scientists? The answer is certainly "yes." But which
aspects of biological knowledge are most useful for social scientists? The answer depends on
what the knowledge project is in the first place. Suppose one is interested in educational reform.
If one's unstated starting assumption is that there are likely to be irreducible cognitive differences
between boys and girls, one is more likely to incorporate biological knowledge which suggests
fixed brain differences between males and females and which goes on to offer evolutionary
explanations for the origins of such difference. Belief in hormonally-induced, hard-wired brain
differences of very ancient evolutionary origin is easiest to reconcile with difference-based
reform-encouraging boys and girls to develop their special but rather different skills. If, on the
other hand, one assumes that on average anyone can learn just about anything (and ought to do so
if they want to), then the views of geneticists who focus on norms of reaction, adaptive plasticity
and context-dependent gene action will appeal. These latter understandings of biology are more
compatible with equity-based reform-the belief that given the right circumstances almost all students can excel.
We each gravitate to the accounts of biology that most suit our social belief systems. Rather
than becoming mired in often inaccurate or partial renditions of biological knowledge, social
scientists can offer something to the world that biologists cannot-thick, complex, multivariate
descriptions of human behavior. It would be a shame if social scientists gave up their skills and
knowledge base in favor of strictly biological accounts of complex human behaviors. Were
biological approaches to stand alone as our sole method of understanding, however interesting
they may sometimes be, they would provide impoverished versions, indeed, of the knowledge
systems offered us by anthropologists, sociologists and psychologists.