[Paleopsych] LibertyGuide.com: Evolutionary Psychology and the Social Sciences
Premise Checker
checker at panix.com
Sat Jul 24 01:01:28 UTC 2004
Evolutionary Psychology and the Social Sciences
http://www.theihs.org/libertyguide/hsr/hsr.php?id=36&print=1
Evolutionary Psychology and the Social Sciences
by [1]Todd Zywicki
From [2]Humane Studies Review Vol. 13, No. 1
Recent years have seen an explosion in interest in evolutionary
biology and its implications for the social sciences. Few areas of
social science research have been untouched by the Darwinian
revolution currently taking place. Economics, sociology, political
science, law, history, psychology, philosophy, and anthropology have
seen Darwinian arguments slowly gravitate from the periphery toward
the center of their disciplines. The purpose of this essay is to
provide an introduction to the field and to suggest future avenues for
further research in the intersection between evolutionary biology and
the humane sciences.
It is a fortuitous time for young scholars interested in the
application of Darwinian evolution to problems of social science.
Increasing understanding of DNA sequencing, combined with the impetus
of the human genome project, have given rise to an unprecedented
understanding of the genetic basis of much of our physical and mental
natures. These developments have also eroded some of the stigma
associated with prior efforts to apply Darwinian evolution to the
study of human society, the most recent being E. O. Wilson's
Sociobiology, which met with a firestorm of protest when published in
the 1975. See E. O. Wilson, Sociobiology: The New Synthesis (1975)
(Cambridge, Mass.: Harvard University Press). Today the field travels
under a variety of names; although the traditional term "sociobiology"
is still occasionally used, more common today is evolutionary
psychology, which is can be classified as a subset of evolutionary
biology of "neo-Darwinism."
The negative political reception of Wilson's Sociobiology set back the
field for an entire generation of social scientists. This means that
there remains a large degree of low-hanging fruit for young scholars
to pluck in forming a research agenda in the field. Moreover, because
much of the science remains fluid and ongoing, working in the field
requires a degree of mental dexterity and the development of new
skills that provides a comparative advantage to younger scholars.
This essay will not attempt to provide a comprehensive guide to the
field of evolutionary psychology. The field is vast and can become
technical very quickly. This essay therefore will only attempt to
provide an overview and introduction to the field. The sources
mentioned will generally be highly comprehensive and generally provide
detailed references for those interested in pursuing issues in greater
depth. Indeed, this work will not attempt to identify more than a
handful of the interesting social science issues that seem to be worth
exploring through the lens of evolutionary psychology. Indeed, this
portion of the essay is avowedly idiosyncratic and subjective, and is
intended primarily to suggest some of the types of questions that can
be gainfully addressed through a Darwinian framework.
In the remainder of the essay I will first discuss why an
understanding of evolutionary psychology is useful for those
interested in studying the social sciences. The next section will
provide an overview of some of the important concepts that have
emerged from evolutionary psychology, focusing in particular on the
"four paths to cooperation" that have been identified by scholars. The
final section will discuss some of the implications of evolutionary
psychology for research in different fields of inquiry.
Why Study Evolutionary Psychology?
Most classical liberals are somewhat skeptical about the value of
studying evolutionary psychology. To some extent this is rooted in the
historical association of classical liberalism with the mistaken
tenets of "Social Darwinism" at the turn of the century. To some
extent this skepticism resides in the frosty reception of sociobiology
by a prior generation of scholars. Finally, to some extent this
skepticism resides in a misunderstanding of the import of evolutionary
psychology, and in particular in the belief that evolutionary
psychology believes in the perfect determinacy of human behavior. This
latter belief makes evolutionary psychology anathema to those
concerned about issues of free will and personal autonomy.
This skepticism is unfounded. Social Darwinism was a perversion of the
insights of evolutionary psychology. Social Darwinists committed the
classic naturalist fallacy, reasoning from the empirical observation
that evolution operated according to the principle of the "survival of
the fittest" to the normative conclusion that it should be the job of
society to weed out the weak so as to further this evolutionary
imperative. In so doing, Social Darwinists jumped from the "is" of
evolution to the "ought" that the product of natural evolution is
morally justified. Interestingly, today some environmentalists are
prone to commit the naturalist fallacy in their belief that somehow
what is "natural" is morally preferable to that which is not. On the
other hand, this does not rule out a belief that what is normatively
good for human beings must in some sense be consistent with their
fundamental psychological natures. See E. O. Wilson, Consilience: The
Unity of Knowledge (New York: Alfred A. Knopf, 1998); R. D. Alexander,
The Biology of Moral Systems (Hawthorne, N.Y.: Aldine De Gruyter,
1987). This latter argument recognizes the "is-ought" gap, so the
naturalistic fallacy is avoided. Nonetheless, it argues that
individuals will flourish only if they act consistently with their
evolved natures. See Owen D. Jones, "On the Nature of Norms: Biology,
Morality, and the Disruption of Order," Michigan Law Review 98:
801-832 (Forthcoming 2000).
Whether a particular behavior is normatively good or bad cannot be
established simply by determining that the actor is "naturally"
inclined to behave in such a manner. Certain behaviors can be good or
bad only according to an external normative standard. Thus, as
discussed below it appears that human beings may be naturally
predisposed to engage in trade, act compassionately, and enter into
reciprocal arrangements for mutual benefit. By almost any moral code,
all of these behaviors are normatively good. By contrast, it also
appears that some human beings may be predisposed naturally toward
violence and rape. See Randy Thornhill and Craig T. Palmer, A Natural
History of Rape: Biological Bases of Sexual Coercion (Cambridge: MIT
Press, 2000); Owen D. Jones, "Sex, Culture, and the Biology of Rape:
Toward Explanation and Prevention," California Law Review 827-941
(1999). The fact that these behaviors are "natural" is irrelevant to
the fact that they are universally morally condemned. Finally, other
predispositions, such as our tendencies to eat too many candy bars,
are morally neutral. The desire to consume sugar served an
evolutionary purpose in an era where food was scarce and it was useful
to have a built-in craving to encourage us to seek food. The task of
the philosopher and social scientist is to understand the degree to
which certain predilections are hard-wired into human psychology, and
thereby to determine what set of institutions and incentives are
necessary to restrain, modify, or channel these predilections into
pro-social behavior and away from anti-social behavior.
Moreover, evolutionary psychology does not imply biological
determinism. Modern biology makes clear, rather, that one's behavior
is a function of the mutual interaction between evolved traits and
one's environment, or as the case is frequently (if inaccurately) put,
between nature and nurture. Indeed, evolution itself is driven by the
interaction of biological variation interacting with environmental
selection. There are no absolute degrees of fitness, only comparative
degrees of fitness relative to a given environment. Evolutionary
psychology simply provides evidence of general tendencies that
interact with an individual's environment. At the same time,
evolutionary psychology rejects the claims of current theorists who
argue that one's personality is entirely socially constructed and thus
infinitely malleable. As Marxists learned the hard way, there are
certain characteristics of human nature that seem to be virtually
impossible to eliminate, such as the tendency to prefer the welfare of
one's family to strangers, the tendency to free ride on others' labors
where possible, and the tendency to seek wealth and status. Thus,
although the morality of a given behavior cannot be determined simply
by whether it is natural, the recognition that there are certain
hard-wired tendencies to human nature may constrain what aspirations
are attainable or may provide guidance as to what tools are available
to accomplish one's goals. Thus, evolutionary psychology illustrates
the folly of the scholarship of recent decades that has tried to
ignore the reality of an innate human nature that is not infinitely
malleable. More fundamentally, it provides a warning against indulging
in the utopian schemes characteristic of the twentieth century, most
of which rested on the supposition that human nature could be molded
to fit the desires of utopian reformers, rather than recognizing the
limits that human nature placed on such schemes.
It is now generally accepted that evolutionary biology provides a
persuasive explanation for our biological natures, e.g., two arms, two
legs, upright gait, vision, hearing, warm-bloodedness, etc. Although
evolutionary biology has triumphed for biological evolution, scholars
remain reluctant to recognize that evolution has psychological
consequences as well. Instead, scholars have preferred to believe that
humans remain a tabula rasa, blank personalities subject to molding by
social, cultural, legal, political, and economic forces. I have
elsewhere dubbed this incongruity, "Darwinism from the neck up,"
because even as secular scholars have generally embraced biological
Darwinism, they have rejected psychological Darwinism with equally
forceful zeal. See Todd J. Zywicki, "The State of Nature and the
Nature of the State: A Comment on Grady and McGuire," Journal of
Bioeconomics 1(3): 241-261 (1999). The flaw in this reasoning is
obvious. Just as we have physically evolved to solve a number of
common problems that arose in our evolutionary environment, we have
similarly developed psychological skills necessary to operate in the
social environment of our evolutionary ancestors. Put more simply,
nobody believes that education or culture will make me physically able
to dunk a basketball; why are Marxists so optimistic that education,
economic, and political reform could make me treat strangers as if
they were my genetic kin?
For most animals the relevant variable for one's evolutionary fitness
turns on the fitness for a given physical environment. Thus, a wolf's
fitness will be a function of its ability to hunt down elk and an
elk's fitness will be a function of its ability to outrun and evade
wolves. For humans, however, the relevant environment primarily is
other humans, a social environment rather than a physical environment.
Because of the immensely social nature of human societies, one's
fitness is not merely a function of the ability to seek prey and to
avoid predation. Rather, human societies place a fundamental premium
on the ability to interact with other human beings in a social
environment. The evolutionary environment for humans is the body of
institutions, rules, customs, and expectations of others. Thus, the
fundamental evolutionary difficulty for humans is to solve inherently
social puzzles as to how to interact with others. Although other
animals have some degree of culture, none of them even approximates
the complexity of even the simplest human cultures. See F. De Waal,
"Cultural Primatology Comes of Age," Nature 399:635-636 (1999). A
massive database has been established to collate the various different
chimpanzee cultures that researchers have identified. See A. Whiten,
et al. "Cultures in Chimpanzees," Nature 399:682-685 (1999). Their
results can be found on-line at
<[3]http://www.chimp-st-and.ac.uk/cultures/database.htm>.
An incongruity arises in that evolutionary psychologists recognize
that the social problems that humans must solve are not actually the
social problems of today's global economy, but that our minds are
molded to solve the social problems of our human ancestors. Our brains
and minds (as with our bodies) took on their current configuration in
what is generally referred to as the Environment of Evolutionary
Adaptedness, or EEA, during the Pleistocene Era several million years
ago. During this time our human ancestors lived in small, stable
hunter-gatherer bands characterized by stable social groups, repeated
interaction over time, and relatively long life spans. In evolutionary
terms a few million years is a relatively short amount of time. Thus
it is believed that humans have largely the same biological natures as
the humans of hunter-gatherer time. Cultural evolution, however,
operates much more rapidly than biological evolution. Thus, we live in
high-speed global economies characterized by rapid economic change,
although our essential natures remain essentially hunter-gatherer in
nature. This creates a mismatch between some of our innate desires and
the realities we confront on a daily basis. See F. A. Hayek, The Fatal
Conceit: The Errors of Socialism (1988) (The Collected Works of F. A.
Hayek, W. W. Bartley III ed., Chicago: University of Chicago Press).
For Hayek, therefore, the purpose of culture and institutions is to
control our self-destructive impulses to impose our small-group
sentiments on modern society. Robert Wright, by contrast, builds on
the foundation of human sociability and argues that biological and
cultural evolution share the common trait that they both have a
tendency toward increasing complexity driven by the mutual benefits of
"non-zero-sum exchange." See Robert Wright, Nonzero: The Logic of
Human Destiny (2000) (New York: Pantheon Books). Unlike Hayek,
therefore, Wright views culture and institutions as the extension of
an innate tendency to engage in mutually beneficial exchange, without
Hayek's emphasis on the small-group setting of the EEA.
Just as the study of evolutionary biology should not be interpreted to
denigrate the importance of environmental factors, it should also not
be interpreted to denigrate the value of free will and purposefulness
in human action. It is true that some commentators such as Robert
Wright have suggested that evolutionary psychology calls into question
the entire concept of free will by reducing human action to a
predictable set of impulses. See Robert Wright, The Moral Animal:
Evolutionary Psychology and Everyday Life (1994) (New York: Vintage
Books). Others, however, have argued that a proper understanding of
science and human nature actually enhances the importance of free will
and moral decision by recognizing the importance of restraining our
anti-social and unhealthy impulses even when tempted to act otherwise.
See Pope John Paul II, "Message to Pontifical Academy of Sciences,"
The Vatican (Oct. 22, 1996). Studying animal behavior and cooperation,
therefore, is useful in the same way that game theory is useful, to
provide evidence of how humans might be predicted to act absent the
restraints of human nature and social institutions and norms. Studying
animal behavior provides insight on possible solutions to various
problems of human societies, such as problems of collective action,
conflict resolution, and the like. Social animals are confronted with
many of the same problems as human societies, of keeping internal
peace and resolving conflicts over scarce resources. And they do so
without any sophisticated cultural or institutional mechanisms. As
evolutionary biologist Lee Dugatkin observes, Lee Dugatkin, Cheating
Monkeys and Citizen Bees: The Nature of Cooperation in Animals and
Humans (New York: Free Press, 1999), studying human behavior and
cooperation:
shows us what to expect when the complex web of human social networks,
as well as the laws and norms found in all human societies, are
absent, and so these studies act as a sort of baseline from which
to operate. Animals show us a stripped-down version of what
behavior in a given circumstance would look like without moral
will and freedom. Only with this understanding of what a
particular behavior looks like outside the context of some moral
code can we use human morality to focus on and foster cooperation
in our species. [4][1]
Four Paths to Cooperation
Thomas Hobbes famously claimed that absent a central political
authority the state of nature would devolve into a war of "all against
all." Selfish individuals, he believed, would be unable to cooperate
for mutual advantage because of the constant temptation for
individuals to take advantage of one another. Stated in modern game
theory terms, Hobbes believed that individuals would "defect" in every
interaction they had with one another. The insights of evolution rebut
Hobbes's belief. All living creatures face certain difficulties
maintaining social cooperation and peace. This section will review the
"four paths to cooperation" that evolutionary biologists have
identified as mechanisms for creating social peace without the
necessity of a central rule-making authority. In fact, most
cooperation in nature exists not only without legal and political
institutions, but also without what has fashionably come to be called
"norms" and which previously was called custom. Norms and institutions
can extended the sphere of cooperation, but it appears that much
cooperative behavior is in fact natural and rooted in human nature. It
is likely that the presence of a hard-wired tendency toward
cooperation is a necessary condition for the emergence of social
cooperation; indeed, in many animal societies it is also a sufficient
condition.
Although Hobbes's solution was utterly confused, he posed the correct
question -- how can selfish individuals be induced to cooperate with
one another? Biologists start with a similar reductionist premise.
Rather than selfish individuals, however, biologists begin their
analysis with selfish genes. See Richard Dawkins, The Selfish Gene (2d
edition, 1989) (New York: Oxford University Press). The two are
closely related but analytically distinct. Genes are the basic units
of natural selection; individuals can be understood as collections of
genes. The only measure of success for a gene is its ability to be
replicated into a new generation. Genes produce phenotypic traits in
human beings, such as intelligence, athleticism, and physical
appearance, that when selected for by the environment, affect an
individual's likelihood of successfully mating and passing along his
or her genetic material to a new generation. Matt Ridley provides an
excellent introduction to the ways in which genotypes are reflected in
specific human phenotypic traits. See Matt Ridley, Genome: The
Autobiography of a Species in 23 Chapters (London: Fourth Estate,
1999). In this sense genes can be figuratively said to be "selfish" in
the same way an individual can be said to be selfish (even though
genes do not act with "intent"); particular genes "care" only about
their own survival into a new generation. Thus, genes are "selfish,"
and do not "care" about the plight of any other genes, except to the
extent that it helps that particular gene survive into the next
generation. In turn, this suggests that individuals will act in the
self-interest of his genes.
This analysis really just restates the basic question: given the
existence of selfish genes, why do we see so many instances of
cooperation among animals, including human beings? Lee Dugatkin
provides a virtual encyclopedia of documentation and explanation of
cooperation among animals in Cooperation Among Animals: An
Evolutionary Perspective (New York: Oxford University Press, 1997).
Moreover, cooperation in non-human animals is especially puzzling,
given the absence of cultural norms or a state to enforce compliance
with cooperative behavior.
Four mechanisms have been suggested by evolutionary biologists to
explain the evolution of cooperation in nature: (1) kin selection, (2)
cooperation for mutual advantage, (3) reciprocal altruism, and (4)
group selection. In each of these situations, one individual (i.e.,
collection of genes) acts altruistically in bestowing a benefit upon
some other individual (collection of genes). This is surprising, in
that it seems to be inconsistent with the self-interest axiom.
Nonetheless, each of these mechanisms potentially makes it more likely
that certain genes will be propagated in a new generation. Sometimes
the benefit for the genes is direct, as in the kin selection model.
For others it is indirect, in that by pursuing cooperation an
individual increases his wealth and health, increasing his
reproductive capacity relative to less cooperative individuals. This
section of the essay will discuss each of these paths to cooperation
in turn.
Kin Selection
Kin selection operates on the premise that the marginal sacrifice of
one individual may make that individual relatively worse off, but that
the sacrifice may also make that individual's genes better off as a
result. For instance, consider the following situation confronting a
family of ground squirrels. Amy the ground squirrel is out foraging
for food one day with her sisters when she spots a hawk circling
above. At this point, Amy has two options: she can either quietly
slink back to the lair, leaving the hawk to eat a less-observant
sister. Alternatively, she can sound a warning call, thereby alerting
Betty, Claire, Denise, Edith, and Francis that a hawk has been spotted
and warning them to retreat to the lair. Assume further that if she
sounds the call, it will increase her likelihood of being eaten by the
hawk by 10% but will reduce the likelihood of her sisters being eaten
by 5% each. Will she call the alarm?
Surprisingly, the answer is yes for Belding's ground squirrels. See
Paul W. Sherman, "Nepotism and the Evolution of Alarm Calls," Science
197: 1246-1253 (Sept. 23, 1977). For a less technical presentation,
see Lee Dugatkin, Cheating Monkeys and Citizen Bees: The Nature of
Cooperation in Animals and Humans (New York: Free Press, 1999).
Although it makes it more likely that Amy will be killed, it makes it
sufficiently less likely that her sisters will be eaten that it is
worth it for her to call the alarm. Even though sounding an alarm call
is dangerous to the individual caller's survival, it is favorable
toward the caller's genes. Individual ground squirrels (as with most
animals) are diploid, meaning that they draw one-half of their
chromosomes from each of their two parents (a female mother and a male
father). This means that on average Amy shares 50% of her genes with
her sisters. Thus, even though Amy's call decreases her likelihood of
surviving the hawk attack by 10%, it increases the overall likelihood
of saving her sisters by 25% (five sisters times 5% increased
likelihood of survival). Because Amy shares on average 50% of her
genes with her sisters, sounding the alarm call will increase the
likelihood of her genes surviving by 12-1/2% overall (25% times 50%),
while costing her only a 10% likelihood of being eaten. Thus, while it
is irrational from Amy's individual perspective to call the alarm, it
is "rational" from her genes' perspective to induce Amy to call the
alarm.
This tendency to act altruistically toward one's kin is called
"inclusive fitness." See W. D. Hamilton, "The Genetical Evolutionary
of Social Behavior, Parts I and II," Journal of Theoretical Biology
7:1-52 (1964); J. Maynard Smith, "Group Selection and Kin Selection,"
Nature 201:1145-1147 (1964). The theory of inclusive fitness predicts
that natural selection will favor altruism among kin: the closer two
individuals are related to one another, the lower the costs to the
altruist, and the greater the benefits to the recipient. Therefore, if
the five individuals that Amy's call would save were grandchildren,
rather than her sisters, each individual granddaughter would have only
a 25% expected relatedness to Amy. As a result, it would be
"irrational" for Amy to sound the alarm, as she would be increasing
her likelihood of being attacked by 10%, but only increasing the
likelihood of her genes' survival by 6.25%. Restated, natural
selection predicts that, on average, we would tend to act more
altruistically toward siblings, parents, and children with whom we
share an average relatedness of 50% than toward grandparents,
grandchildren, aunts, and uncles, with whom we share an average
relatedness of only 25%. Interestingly, this theory also provides no
instinctive reason why we would act more altruistically toward a
spouse than toward a stranger. Thus, the observed tendency to act
altruistically towards one's spouse must rest on some other basis than
the theory of inclusive fitness.
This is not to imply that ground squirrels make such rational
calculations in deciding whether to issue an alarm in a given
situation ("Let me see, how many sisters and granddaughters are around
right now..."). There is a burgeoning literature on how animals
determine who is kin and who is not. See P. G. Hepper, Kin Recognition
(Cambridge: Cambridge University Press, 1991). Most of the methods of
identification, such as close inspection of physical features or
odors, are relatively costly to perform. Thus, rather than engaging in
a close inspection of every member of an animal society, most animals
seem to rely on the simple heuristic of treating as kin everyone who
grew up in the relevant area (e.g., nest, territory, burrow, etc.). As
a rule of thumb, this approach is subject to error, most notably by
animal parasites who try to trick other animals into raising their
offspring (suck as cuckoos). But in general, treating those with whom
you grew up as kin provides a pretty accurate shortcut for determining
who is kin and who is not. Thus, it is interesting to note that the
so-called "incest taboo" of not being attracted to kin actually
appears to be not so much an aversion on being attracted to a
relative, but instead is an aversion against being attracted to a
person with whom you grew up. See E. A. Westermarck, The History of
Human Marriage (New York: Macmillan, 1891). Thus, stepsiblings raised
together are rarely attracted to one another, as are very close
childhood friends. By contrast, this further suggests that if sexual
activity takes place within the family, the most common type will be
between father and daughter, because the father is beyond the age
where familiarity breeds aversion. See M. Daly and M. Wilson, Sex,
Evolution, and Behavior (2d ed., Belmont, CA: Wadsworth, 1983).
So there is no rational calculation as to whether to make an alarm
call. The analysis suggests instead that ground squirrels would
develop an instinct to call alarms when they are near their homes
because in general they will be surrounded by multiple close family
members and on net it will help the squirrels genes to reproduce. This
instinct is merely a tendency, and in fact ground squirrels suppress
this instinct when environmental conditions change. First, it is only
female ground squirrels who sound alarm calls. This is because in
ground squirrel communities males emigrate, while females remain in
kin groups. Thus, males tend to be surrounded by individuals with whom
they have no genetic relation, thus they become purely interested in
their own personal survival. Second, studies have been done of the
rare situations where female ground squirrels have been forced to
emigrate to new groups. Sure enough, these newcomers are less likely
than the incumbents to give alarm calls.
Kin selection also explains why ant colonies and beehives have such a
high degree of cooperation. Many ants are actually sterile and do not
reproduce at all, the ultimate act of individual self-sacrifice. But
individual self-sacrifice is not genetic self-sacrifice. Most
creatures are diploid for purposes of reproduction, meaning that an
offspring requires both a mother and a father for a fertilized egg to
reproduce, and therefore draws half her genes from her father and half
from her mother, making for a 50% degree of genetic relatedness. Ants,
by contrast, are haplodiploid: females are diploid and have two sets
of chromosomes (one from each parent), but males arise from
unfertilized eggs, thus they only have a mother and have only one set
of chromosomes. Unlike most creatures who share a 50% expected genetic
relatedness with siblings, ants share an expected 75% expected genetic
relatedness with siblings. This high degree of genetic relatedness
explains the remarkable social cohesion among ant communities as well
as the willingness of individual ants to sacrifice their individual
reproduction in order to tend to the feeding and raising of others'
offspring.
The pull of kin selection, for instance, may explain why it is that
the law tends not to contractually enforce promises made between
family members. See Charles J. Goetz and Robert E. Scott, "Enforcing
Promises: An Examination of the Basis of Contract," Yale Law Journal
89: 1261-1359 (1980). Kin selection suggests that at some base level
the utility functions of family members are interdependent, and that,
for instance, mothers and fathers will tend not to act
opportunistically with respect to their children. As a result, when a
family member fails to carry through on a promise, we can assume with
a high degree of reliability that the breach was due to a sincere
regret contingency and was not merely an opportunistic breach. This
analysis will also have implications for rules governing inheritance
law and other familial relations.
On the other hand, it has also been argued that the absence of genetic
relationships may help to explain the relatively higher degree of
abuse of children raised by stepparents relative to those raised by
their natural parents. See M. Daly and M. Wilson, Homicide (Hawthorne,
NY: Aldine, 1988); Owen D. Jones, "Evolutionary Analysis in Law: An
Introduction and Application to Child Abuse," North Carolina Law
Review 1117-1242 (1997). It has been argued that courts should
consider such statistical regularities in making child-custody
determinations in the event of divorce. See Robin Fretwell Wilson,
"Children At Risk: The Sexual Exploitation of Female Children After
Divorce," Cornell Law Review 86(2) (Forthcoming 2000).
Finally, the innate pull to take care of one's genetic relations has
obvious implications for how we think of society as a social organism.
It is suggestive of the visceral appeal used in times of war for
individuals to pull together with their "brothers and sisters." It
also evidences the folly in some current schemes to break down the
family as the basic social unit of society. Kin selection theory
suggests that it is the family, even more than the individual, that is
the basic social unit of society. Thus, while utopian reformers may
talk about treating strangers as one's brothers, this rhetoric really
tends to miss the point.
For kin-based altruism to flourish, little is required in the way of
conscious action. Also, its payoff in terms of reproductive fitness is
quite direct. Unsurprisingly, therefore, kin-based altruism is
ubiquitous in nature. In fact, it is often cited as a basic building
block of other forms of altruistic behavior.
Cooperation for a Given End
A second form of altruistic behavior is cooperation for a given end,
or by-product mutualism. Cooperation for a given end exists when there
is some goal that can be best accomplished through a group of
individuals working together, rather than acting separately. In such
situations there is a payoff from teamwork, so long as it is possible
to monitor the members of the team to make sure that contribute to the
final output.
Group hunting provides an excellent example of cooperation for a given
end. A pack of wolves hunting together, for instance, will be able to
capture more and different types of game than the same wolves hunting
alone. Similarly a group of hunter-gatherers generally can capture
more and larger game than individual hunter-gatherers hunting alone.
In this model, therefore, cooperation arises from the self-interest of
the various members of the group. Each of the members of the group
benefits individually from the larger production that can be generated
by hunting together as a team rather than hunting alone. Hunting
together, therefore, produces a social surplus relative to what would
be produced hunting individually. For instance, assume that five
members of a hunter-gatherer band could, hunting alone, capture one
rabbit apiece (five total), but that no single individual could bring
down a woolly mammoth. Assume further that if the five individuals
worked together, they could kill a woolly mammoth that would provide
the food equivalent of eight rabbits. The social surplus from hunting
together, therefore, would be the equivalent of three additional
rabbits.
But there are also costs that are potentially incurred as a result of
cooperation for a given end. Group activity raises the threat of free
riding by members of the group. For instance, it may be that it is
much more dangerous to hunt woolly mammoths than rabbits. Thus, each
individual member of the hunting party will have some incentive to lay
back and free ride on the efforts of the other members of the party.
This may reduce the probability of slaying the mammoth; at the very
least it will allow the coward to capture a share of the social
surplus despite his unequal contribution to its production. It is
interesting, therefore, that societies predicated on a high degree of
group hunting have devised a number of norms and practices designed to
limit shirking.
First, food sharing (absent reciprocal relationships, which are
discussed below) is limited only to those goods that actually require
joint production to be produced. Thus, for instance, fruits and
berries are generally collected through female effort. This production
requires no team production, thus labor inputs are directly reflected
in the amount of food outputs generated. As a result, these food
products are generally consumed within the family and not shared.
Among the Ache of Paraguay, plant food and insect grubs are not shared
outside the nuclear family, although meat is. Among the Yora of Peru,
on "a fishing trip, everybody shares; back at the camp, food is freely
shared only in the family, and at all times meat is more widely shared
than vegetables. Thus, while fish, monkeys, alligators and turtles are
shared, plantains are hidden in the forest until they ripened to
prevent neighbors stealing them." [5][2] See Matt Ridley, The Origins
of Virtue: Human Instincts and the Evolution of Cooperation (New York:
Viking, 1996). See also K. Hill and H. Kaplan, "Population and
Dry-Season Subsistence Strategies of the Recently Contacted Yora of
Peru," National Geographic Research 5: 317-334 (1989).
Second, group hunting is generally engaged in only when economically
efficient. Thus when pursuing small game, animals tend to hunt
individually, but when pursuing large game requiring teamwork, animals
hunt together. See Dugatkin, Cheating Monkeys at 114-116; D. Scheel
and C. Packer, "Group Hunting Behavior of Lions: A Search for
Cooperation," Animal Behavior 41: 697-709 (1991). Fish also tend to
forage individually unless their environment requires them to hunt
together. For instance, it is impossible for an individual or even a
small group of wrasse to penetrate the defenses of a single
damselfish. Working together in coordinated action, however, a large
group of wrasse can distract and overwhelm the damselfish's defenses.
Thus, it appears that wrasse work together in plundering damselfish
eggs but forage separately when coordinated action is not as
necessary. See S. A. Foster, "Acquisition of a Defended Resource: A
Benefit of Group Foraging for the Neotropical Wrasse, Thalassoma
lucasanum, Environmental Biology of Fishes 19: 215-222 (1987); R. J.
Schmitt and S. Strand, "Cooperative Foraging by Yellowtail Seriola
lalandei (Carangidae) on Two Species of Fish Prey," Coeia 1982:
714-717. Where teamwork is unnecessary the gains to group hunting are
small, but the problems of preventing free riding remain constant. As
a result, group hunting will be less common.
Third, unusually good hunters are rewarded with a disproportionately
large share of the social surplus. Skilled chimpanzees, for instance,
get first choice of the meat from slain prey, as well as retain
primary responsibility for distributing the spoils. See Frans de Waal,
Good Natured: The Origins of Right and Wrong in Humans and Other
Animals (Cambridge, MA: Harvard University Press, 1996). Skilled
hunters in primitive human societies are rewarded not only with
primary hunting spoils but also with disproportionate sexual favors
from women, who often directly exchange sex for meat. See K. Hill and
H. Kaplan, "Tradeoffs in Male and Female Reproductive Strategies among
the Ache," in Human Reproductive Behavior (L. Betzig, M. Borgehoff
Mulder, and P. Turke eds., Cambridge: Cambridge University Press,
1988); K. Hill and H. Kaplan, "On Why Male Foragers Hunt and Share
Food," Current Anthropology 34:701-706 (1994); for a slightly
different argument see K. Hawkes, "Why Hunter-Gatherers Work: An
Ancient Version of the Problem of Public Goods," Current Anthropology
34: 341-361 (1993).
Interestingly, the bulk of this analysis rebuts the traditional myth
that primitive societies are socialist in orientation. As discussed
below, it is true that they are highly egalitarian in their social
arrangements (at least as compared to other species), but this social
egalitarianism is often misunderstood as economic socialism. Neither
chimpanzee bands nor human hunter-gatherer societies are socialist. I
am aware of no human or animal society that has sustained an ethic of
unconditional sharing of social surplus for very long. It is true that
large game is, in fact, shared. But a good deal of sharing is sharing
among kin, which is predicted by the kin-group selection model
described above. As to non-kin, animal and human societies universally
practice an ethic of conditional sharing. An able-bodied individual
who could work but chooses not to has no entitlement to the any amount
of the social surplus. Male chimpanzees who attempt to free ride by
trying to participate in eating without participating in hunting "tend
to receive little or nothing." [6][3] See also C. Boesche and H.
Boesch, "Hunting Behavior of Wild Chimpanzees in the Tai Nation Park,"
American Journal of Physical Anthropology 78: 547-573 (1989); C.
Boesch, "Cooperative Hunting in Wild Chimpanzees," Animal Behavior 48:
653-667 (1994). At the very least, those who fail to contribute are
given the last pick of any meat available, and this is simply because
large game will spoil on the open plains (where refrigerators
traditionally have been somewhat scarce). Thus, the effective marginal
cost of giving food to shirkers in this situation is zero.
In contrast to this strictness of dealing with able-bodied shirkers,
weak and infirm individuals are often accorded special treatment and
protection from other members of the relevant society, even in
chimpanzee societies. Compassion and sympathy toward those who are
unable to help themselves appear to be as much a part of human nature
as the unwillingness to feel much sympathy for shirkers who
subsequently seek to share in the social product. This may account for
the universal tendency to distinguish "worthy" from "unworthy"
recipients of charity. [A somewhat similar analysis is provided in Amy
Wax, "Rethinking Welfare Rights: Reciprocity Norms, Reactive
Attitudes, and Political Economy of Welfare Reform," Law and
Contemporary Problems (Forthcoming Fall 2000)]. We seek to help those
who are unable to help themselves, but we are outraged when our
charity is exploited by those who could help themselves but choose not
to do so. The contextual nature of food-sharing is a theme that I will
return to below.
The problem of cooperation for a given end is identical to the problem
confronted by an economic firm. See A. Alchian and H. Demsetz,
"Production, Information Costs, and Economic Organization," American
Economic Review, 62: 777-795 (1972). Alchian and Demsetz argue that
the economic function of a firm is team production. Team production
can produce outcomes that are unavailable to uncoordinated individuals
working alone. They provide the example of moving a couch: no single
individual could do it, but four men can do it easily. Thus, there is
social surplus as a result of the team production. The problem is that
each individual will have an incentive to "shirk" by not working as
hard as the other members of the team. Each member of the team faces
the same incentives; thus, unless the shirking problem can be
contained, either the couch will not get moved, or it will take more
time than it would otherwise, thereby reducing the effective social
surplus. Alchian and Demsetz argue that, in response to these
incentives, some individual will be designated to be a residual
claimant whose primary responsibility will be to constrain shirking by
the team members. In return, the residual claimant will be rewarded
out of the general social surplus. The economic organization of the
firm faces virtually identical opportunities and problems as the wolf
pack seeking to bring down an elk.
Cooperation for a given end is an important component of cooperation
in nature, but it is limited in its utility to serve as a general
mechanism for social coordination. Cooperation for a given end
presupposes the existence of some uniform goal that all members of the
team seek to attain. Society and economy, however, are characterized
by a plurality of ends, not a single uniform end. See F. A. Hayek, The
Road To Serfdom (Chicago: University of Chicago Press 1944); Adam
Smith, The Theory of Moral Sentiments (Indianapolis: Liberty Classics,
1976). Thus, although cooperation for a given end is valuable in
allowing individuals to accomplish their individual goals, it does not
provide a general theory for organizing society. See Michael Polanyi,
The Logic of Liberty (Chicago: University of Chicago Press, 1951);
Todd J. Zywicki, "Epstein and Polanyi on Simple Rules, Complex
Systems, and Decentralization," Constitutional Political Economy 9:
143-150 (1998). At the level of the social abstraction of an economy
and a society, the fundamental question is how to coordinate these
disparate goals peacefully and efficiently.
The appeal of organizing society so as to accomplish a given goal
explains the appeal to many social thinkers of a society and economy
at war. During such times, it is argued, individuals suppress their
plurality of individual goals in favor of attaining a goal that is
good for society generally, namely conquest of the common enemy. After
such wars end, however, there is a tendency for this uniformity of
vision to falter, and individuals return to their individual purposes.
As the foregoing has suggested, this duality is natural. Thus, while
the hunt is on, there are incentives for each individual to contribute
to the common goal of capturing prey. As soon as the prey is downed,
however, each individual quickly turns toward attempting to acquire
for himself as much as possible of the common surplus. Evolutionary
biology teaches us that selfishness is the norm, but that short-term
selfishness can sometimes be subsumed into a joint project. Sometimes
this joint project can be protection from a common enemy. See
Dugatkin, Cheating Monkeys. In the end, however, where cooperation is
for some common goal, each individual participates in furtherance of
his self-interest.
Robert Putnam's book Bowling Alone presents an interesting recent
example of the error of viewing all of society as having a common
purpose, and as all members of society working cooperating to
accomplish this end purpose. See Robert D. Putnam, Bowling Alone: The
Collapse and Revival of American Community (New York: Simon &
Schuster, 2000). Putnam glorifies the effect of World War II in
inculcating a heightened sense of civic responsibility in those who
fought the war, a commitment that continued after the war's
conclusion. Putnam relishes "the moral equivalent of war" without the
bloodshed and disruption of war. [7][4] Thus, Putnam endorses the
role played by the post-war organs of civil society in building a
civic-mindedness aimed at solving collective problems. In stressing
these unifying purposes of civil society, Putnam ignores a second,
equally important strand of scholarship on civil society, namely the
role of civil society organizations in fulfilling a plurality of
individual ends. This strand of analysis, exemplified by scholars such
as Hannah Arendt and Ernest Gellner, stress the importance of civil
society as serving as a guardian of individual liberty and as a
counterweight to the tendency of the state to atomize individuals into
democratic rent-seekers and to infantilize individuals into passive
recipients of the state's largesse. See Hannah Arendt, The Origins of
Totalitarianism (New York: Harcourt Brace & Company, 1973); Ernest
Gellner, Conditions of Liberty: Civil Society and Its Rivals (London:
Hamish Hamilton, 1994). A full understanding of the vital role played
by civil community in a free society requires understanding that the
organs of civilization not only help to build social unity in the
sense offered by Putnam, but also to preserve a sphere of personal
autonomy and pursuit of a diversity of human ends in the sense
identified by Arendt and Gellner.
Cooperation for a given end is relatively common in nature. Where the
benefits to coordination for a given end are sufficiently large (such
as group hunting) and it is possible to constrain shirking and free
riding, the ability to cooperate to accomplish a given end is likely
to emerge spontaneously and to become hard-wired in an animal's
instinctive nature. Moreover, such coalition actions tend to arise
only where necessitated by the environment, and thus such coalitions
can be quite fluid and temporary. More stable coalitions tend to be
held together by the glue of reciprocal altruism, where gains are
provided over time, rather than the more direct and short-term gains
offered by cooperation for a given end.
Reciprocal Altruism
A third basis for cooperation in nature is "reciprocal altruism."
Although termed "altruism," like kin selection and cooperation for a
given end, reciprocal altruism is really rooted in self-interest. But
the mutual gains from reciprocal altruism are produced over time
rather than through a single interaction, as with cooperation for a
given end. In reciprocal altruism an individual provides a benefit for
another in exchange for a reciprocal benefit, or the expectation of a
reciprocal benefit in the future. Because the benefits are traded over
time, however, at the outset one of the individuals must provide a
benefit (thereby incurring a cost) in exchange for the mere
expectation of a reciprocal benefit. By being the first mover, the
party that first incurs a cost for another's benefit can be said to
act altruistically, even though the cost is incurred in expectation of
a long-term benefit. Assuming that the expectation is eventually
realized, this series of reciprocal exchanges over time is called
reciprocal altruism. Robert Trivers, generally credited with
identifying the model, defines reciprocal altruism as "the trading of
altruistic acts in which benefit is larger than cost so that over a
period of time both enjoy a net gain." See Robert Trivers, Social
Evolution (Menlo Park, CA: Benjamin Cummings, 1985); see also Robert
L. Trivers, "The Evolution of Reciprocal Altruism," Quarterly Review
of Biology 46: 35 (1971). Frans de Waal similarly observes,
"Cost-benefit analyses are the staple of evolutionary arguments. The
premise is always that there must be something in it for the
performer, if not immediately then at least in the long run, and if
not for him then at least for his relatives." [8][5] De Waal defines
three characteristics of reciprocal altruism:
1. The exchanged acts, while beneficial to the recipient, are costly
to the performer.
2. There is a time lag between giving and receiving.
3. Giving is contingent on receiving.
Because the benefits to the giver of reciprocal altruism are generated
indirectly (unlike the direct benefits of kin selection) and over a
long period of time (rather than in a relatively discrete transaction,
as with cooperation for a given end), a system of reciprocal altruism
requires a large number of supplementary psychological and social
institutions to develop. On a psychological level, reciprocal altruism
requires that those bound up in the reciprocal relationship have
sufficient cognitive ability to recognize and remember the degree of
their reciprocal relationships with others. On a social level,
reciprocal altruism requires sufficient stability of population that
the long-term benefits of social cooperation can accrue over time. As
de Waal poses the challenge, "Reciprocal altruism differs from other
patterns of cooperation in that it is fraught with risk, depends on
trust, and requires that individuals whose contributions fall short be
shunned or punished, lest the whole system collapse." [9][6] Because
of the huge number of supplementary psychological and social
institutions necessary to run a system of reciprocal altruism, this
form of cooperation is relatively rare in nature, being confined to
only the "brainiest" and most social of animals. Again the analysis
turns on the relative benefits and costs of this form of cooperation
relative to others.
The benefits of reciprocal altruism are potentially large. A system of
reciprocal altruism potentially creates huge social surplus to be
captured by the society. By allowing trade over a period of time,
reciprocal altruism opens up the possibility of a division of labor
and credit-based relationships. These innovations make possible the
recognition of the gains from specialization, comparative advantage,
and the insurance and risk-shifting elements of inter-temporal trade.
More fundamentally, absent the possibility of reciprocal altruism,
every interaction between strangers would be essentially a one-shot
prisoner's dilemma game, with mutual defection as the dominant
strategy. Of course, as the foregoing has indicated, a failure to
solve the problem of reciprocal exchange would not mean the end of all
cooperation -- kin-based cooperation and some degree of cooperation
for a given end would continue. So, for instance, a sex-based division
of labor (presumably driven by kin-based cooperation) is universal in
human societies and is not likely to be the result of mere norms
working alone. See Donald E. Brown, Human Universals (New York:
McGraw-Hill, 1991). Cooperation for purposes of accomplishing a given
goal might also be possible, but even this may break down if there is
some need to devise a system of cooperation outside of the joint
project (such as how to divide the surplus of the group activity,
i.e., how tigers will divide an impala carcass if there is not enough
for each to eat to satisfaction).
But reciprocity opens the possibility of social surplus on a scale
unimaginable for kin-based and by-product cooperation. See Robert
Wright, Nonzero: The Logic of Human Destiny (New York: Pantheon Books,
2000). Indeed, Matt Ridley has argued that what makes human beings
unique is the division of labor, which allows for maximum realization
of gains from trade and reciprocal relations. See Matt Ridley, The
Origins of Virtue: Human Instincts and the Evolution of Cooperation
(New York: Viking 1996). For instance, if six hunters establish an
arrangement to share food over time (allowing for temporarily unlucky
hunters and lucky hunters to share together), it is estimated that
they will reduce the variance in their food supply by eighty percent
relative to hunters who do not share their game. The ability to trade
different types of products (rather than just trading meat
inter-temporally) opens up the possibility of even greater exchange,
such as the possibility of trading axes for spears, or spears for
vegetables. One man may be good at fishing and another at hunting;
there are clear benefits to trading fish for meat in such
circumstances.
As noted, however, reciprocal altruism raises a classic prisoner's
dilemma. If you give me meat today, how do you know that I will give
you meat next week when I am the lucky one? Wouldn't I be better off
to take your meat today and stiff you when you come open-handed next
week? If so, then you will be unwilling to share with me today. The
classic prisoner's dilemma problem of mutual defection seems to
prevail.
Of course, it is now known that this analysis is too facile. Once the
possibility of repeated interactions in the prisoners' dilemma
scenario is introduced, then it is possible for cooperation to result
from these interactions. A stable cooperative outcome can result if
the gains from long-term interactions exceed the gains to one party
from a one-shot defection of acting opportunistically toward the
trading partner. Although a number of scholars hit upon this analysis
at approximately the same time in the late 1970s and early 1980s, the
most famous was probably Robert Axelrod, who popularized the notion
that the "repeat" or "iterated" prisoners' dilemma provides a
cooperative solution to the prisoners' dilemma game. Axelrod famously
ran a computer game where he determined that the optimal strategy to
play in such a game was one of "tit for tat," where the player
cooperates so long as his trading partner cooperates, then punishes
those who defect. See Robert Axelrod, The Evolution of Cooperation
(New York: Basic Books, 1984). It may be less well-known to readers of
this article that Axelrod wrote a subsequent article with biologist
William D. Hamilton (the "inventor" of kin-selection, as discussed
above) where they ran the same experiment to study evolutionary
systems. See Robert Axelrod and William D. Hamilton, "The Evolution of
Cooperation in Biological Systems," Science 211: 1390-1396 (1981);
reprinted in Axelrod, The Evolution of Cooperation, Chapter 5. Rather
than accumulating points, as in the first game, this time Axelrod and
Hamilton's players accumulated "offspring" who were "genetically
programmed" to play the same strategy as their "parents." Thus,
successful strategies would reproduce more rapidly than unsuccessful,
leading to more offspring over time. Playing the game in evolutionary
time, Axelrod and Hamilton discovered that tit for tat was again the
optimal strategy to play, leaving the most genetic offspring. This
suggests that there would an evolutionary benefit for those who
develop a natural tendency to engage in guarded cooperation of the tit
for tat strategy. Moreover, once established, tit for tat is an
"Evolutionary Stable Strategy," or "ESS," meaning that it cannot be
invaded by a small group of outsiders playing some other strategy.
Given the ease with which tit for tat can arise in a community, as
well as its "robustness" and adaptability in a wide variety of
evolutionary contexts, Axelrod and Hamilton suggest that it is likely
that human beings have evolved a natural predilection to engage in
guarded cooperation of the tit for tat variety. This hard-wired
predilection toward cooperation stands in sharp contrast to the
always-defect advice of the Hobbesian worldview that has dominated
liberalism for centuries. Subsequent investigators have questioned
Axelrod's conclusion that tit for tat is the optimal evolutionary
strategy, instead proposing refinements to tit for tat, such as
"Pavlov" and "Firm-but-fair." Although these variations question
whether tit for tat is a uniquely best strategy in the repeat
prisoners' dilemma situation, they are sufficiently similar to tit for
tat so as to reinforce the conclusion of the evolutionary value of
pursuing a strategy of guarded generosity.
The instinctive nature of reciprocal altruism is illustrated by
vampire bat societies. Vampire bats must eat every 48-60 hours or
perish. Vampire bats feed on the blood of cattle and horses. These
mammals are wary and large enough to brush off bats if they are
noticed. Thus, substantial skill is required for a bat to locate prey
and to successfully feed. In fact, on any given night, a large
percentage of bats (especially young bats) will be unsuccessful in
feeding, which would lead to a large number of deaths. To guard
against this eventuality, vampire bats have devised a network of
relationships where successful bats on any given night share excess
blood with unsuccessful bats. Although much of this is sharing between
kin, a substantial amount of sharing is between non-related bats.
Sharing among non-related bats appears to be driven by reciprocal
altruism, or more specifically, a tit for tat relationship. Any given
bat is more likely to share with a bat that has shared with him in the
past than a mere stranger. Stingy neighbors are later rebuffed. See
Gerald S. Wilkinson, "Reciprocal Food-Sharing in the Vampire Bat,"
Nature 308: 181-184 (March 8, 1984). Successful bats have an ability
to detect which bats are most in need of blood, and hence share with
them first. This maximizes the marginal benefit to the recipient bat
and minimal marginal cost to the donor. More importantly, it turns out
that vampire bats have an uncanny ability to recognize one another as
individual bats. This is essential for reciprocity to prevail, as it
enables bats to discriminate among one another in deciding to whom to
donate food. Thus, it is also not surprising that for their size,
vampire bats have unusually large neocortex regions of their brains.
The neocortex region of the brain is responsible for processing
information relating to social arrangements, such as the reciprocal
relationships described. Humans, of course, have tremendously large
neocortex regions relative to our body sizes, reflecting the
complexity of our interpersonal and social relationships. In fact, a
significant proportion of our brain's resources are devoted to the
task of recognizing individual faces. Ridley, Origins of Virtue, at
69. Vampire bats also have relatively long lifespans and a relatively
low degree of social out-migration. As will be discussed below, these
social conditions also help to sustain a system of reciprocal
altruism. As Matt Ridley sums up Wilkinson's research, "Wilkinson
found that [the bats] seem to play Tit-for-tat. A bat that has donated
blood in the past will receive blood from the previous donee; a bat
that has refused blood will be refused blood in turn. Each bat seems
to be quite good at keeping score.... Reciprocity rules the roost."
[10][7]
Given the immense benefits offered by reciprocal trade, why isn't it
ubiquitous in nature? In addition to vampire bats, reciprocal
relationships have been identified in species as diverse as vervet
monkeys, sea bass, fig trees and fig wasps, baboons, chimpanzees,
dolphins, and whales. As suggested above, the main reason is that it
is costly to run a system of reciprocity, both psychologically and
socially. In general, it is only the brainiest species that have
sufficient cognitive capacity to remember not only individual
identities, but to associate discrete patterns of sharing with each
individual. Moreover, the brain is an extremely expensive organ to run
in terms of caloric consumption. Thus, large brains will tend to
evolve only where sufficient environmental forces require them to do
so. In general, only highly social species such as chimpanzees,
dolphins, and whales have sufficiently complicated social structures
to require large brain capacities.
In addition to requiring sufficient cognitive power, reciprocal
altruism requires specific social conditions to prevail. Reciprocal
altruism requires that individuals will interact repeatedly and over
long periods of time. The benefits of long-term interaction are
sufficiently large to reward long-term cooperative behavior and also
make it possible to punish those who do not cooperate. In turn, this
requires a relatively small and stable social group characterized by
repeat interactions among the members of the group. The relationships
of the group must be largely egalitarian, thus making it feasible for
one individual to punish another. In a highly hierarchical society, it
may not be possible for a subordinate to punish someone who is
higher-ranked in the dominance hierarchy. Life spans must also be such
that the "shadow of the future" is sufficiently long for parties to
garner the mutual benefits of long-term reciprocal relations. Finally,
long-term parental care and extensive relationships with relatives
encourage the development of reciprocal altruism; the presence of
cooperation with kin relations provides a "core" group of cooperation
that can allow reciprocal cooperation to spread to unrelated
individuals. [11][8]
Few creatures will meet the three conditions necessary for reciprocal
altruism to flourish: (1) sufficient benefit from reciprocal altruism
in light of one's environment, (2) sufficient cognitive capacity to
process the information necessary to maintain a system of reciprocity,
and (3) the long-term, egalitarian, stable social relationships
sufficient to maintain reciprocal relationships. On the other hand,
humans appear to be uniquely well-suited to developing reciprocal
altruism. "During the Pleistocene, and probably before," Trivers
writes, "a homonid species would have met the preconditions for the
evolution of reciprocal altruism; for example, long lifespan, low
dispersal rate, life in small, mutually dependent and stable social
groups, and a long period of parental care leading to extensive
contacts with close relatives over many years." [12][9] Moreover,
early human society was also highly egalitarian, making reciprocal
benefits and punishments available to all. As Matt Ridley states
Trivers's point, "Of all the species on the planet most likely to
satisfy the criteria of prisoners' dilemma tournaments -- the ability
to meet repeatedly, recognize each other and remember the outcomes of
past encounters... -- human beings are the most obvious. Indeed, it
might be what is special about us: we are uniquely good at reciprocal
altruism." [13][10]
This analysis suggests that like other animals, humans may have a
"reciprocity instinct," a hard-wired predilection for cooperation
combined with the development of psychological skills and social and
cultural norms designed to reinforce this reciprocity instinct. As
noted, reciprocal altruism is evident in some animals, and humans have
the requisite biological and social organizations that make humans
fertile for planting the seeds of reciprocal altruism. In addition, it
appears that the tendency toward reciprocity is universal, not
culture-specific. For instance, my research has uncovered no culture
or religion where it is morally neutral to file bankruptcy and default
on one's financial obligations. See Todd J. Zywicki, "The Reciprocity
Instinct: An Evolutionary Analysis of Norms, Promise-Keeping, and
Bankruptcy Law" (working paper, George Mason University School of Law,
October 28, 1999). Like the incest taboo, the universal nature of the
anti-bankruptcy promise-keeping norm suggests that the norm may in
fact be a hard-wired product of natural selection and the
psychological modules necessary to operate a society on the principle
of reciprocal altruism.
If humans do, in fact, have a reciprocity instinct, the consequences
of this insight are profound. In particular, it suggests that the
recent interest in "norms" theory in legal scholarship is incomplete.
See Eric A. Posner, Law and Social Norms (Cambridge: Harvard
University Press, 2000); Robert C. Ellickson, Order Without Law: How
Neighbors Settle Disputes (Cambridge, MA: Harvard University Press,
1991); Richard H. McAdams, "The Origin, Development, and Regulation of
Norms," Michigan Law Review 96: 338-433 (1997). To be sure, these
scholars are correct in identifying the strong tendency humans exhibit
to establish voluntary and spontaneous norms to resolve potential
disputes arising from day-to-day interactions. But their emphasis on
the social construction and transmission of norms is incomplete. The
foregoing discussion suggests that a theory of norms is flawed without
accounting for the hard-wired tendencies of human beings to generate
reciprocal relationships. Indeed, it is striking that most important
norms are largely universal, and only slightly context-dependent. This
includes such things as telling the truth and keeping one's promises,
as well as emotions such as love, friendship, compassion, vengeance,
and the like. See Donald E. Brown, Human Universals (New York:
McGraw-Hill, 1991). Absent compulsory control, human behavior is a
combination of a hard-wired reciprocity instinct combined with
cultural norms. It is striking, however, that vampire bats, sea bass,
and chimpanzees all exhibit promise-keeping and reciprocal
relationships without any social norms instructing them to do so. An
evolution-based model of reciprocity also avoids the problem of having
to develop complicated and fairly implausible models of
norms-internalization that fail to explain the presence of reciprocal
behavior in non-human species, in children, and in cross-cultural
interactions. For instance, Robert Frank has observed that most of the
signals used to determine one's reliability in a social context are
actually involuntary. See Passions Within Reason: The Strategic Role
of Emotions (New York: Norton, 1988). For instance, an attempt to lie
about the truth is generally met with an involuntary blush, stammering
speech, and shifty eyes. It is hard to see how these wholly
involuntary actions could be triggered a conscious learning about the
impropriety of not telling the truth. It is far more likely that we
have evolved in such a way as to trigger involuntary physical
manifestations of a hard-wired knowledge about the impropriety of
lying. Similarly, we seem to have instinctive "truth-detection" skills
designed to read individuals to determine whether they are telling the
truth. It further appears that the facial expressions that accompany
certain emotional states also are universal rather than
culture-specific. See Darwin and Facial Expression: A Century of
Research in Review (Paul Ekman ed.) (New York: Academic Press, 1973).
In fact, the current state of norms theory is remarkably similar to
the state of cultural anthropology a decade or two ago. Fascinated
with issues of relativism, cultural anthropologists focused on the
task of documenting largely trivial differences between different
societies. Introducing evolutionary psychology into the equation has
opened a much more important and fruitful examination of the
underlying similarities among most cultures throughout the world and
throughout history. See The Adapted Mind: Evolutionary Psychology and
the Generation of Culture (Jerome H. Barkow, Leda Cosmides, and John
Tooby eds.) (New York: Oxford University Press, 1992). This essay is
in part an opening attempt to propose a similar approach to norms
theorists in the law to ground themselves in a stronger theory of
human nature and social evolution.
Group Selection
A final potential path to cooperation is offered by the possibility of
group selection. This is the most controversial of the approaches
offered here, and most evolutionary thinkers remain highly skeptical
of the importance, if not the very concept, of group selection.
Nonetheless, recent scholars have argued that the concept is in fact
viable, rendering it an empirical question as to whether it has
operated in practice. See Elliott Sober and David Sloan Wilson, Unto
Others: The Evolution and Psychology of Unselfish Behavior (Cambridge:
Harvard University Press, 1998). Despite the skepticism that has
generally surrounded group selection, it represents a potentially
powerful method for generating social cooperation on a scale exceeding
all of the foregoing. Reciprocal altruism is most compelling in
providing a theory of cooperation in small-group, face-to-face
settings; although it can be extended from these relations of specific
reciprocity to general reciprocity on a society-wide basis, this step
is tenuous. By contrast, group selection holds out the possibility of
encouraging cooperation on a large-scale society-wide basis directly.
Group selection arguments come in two forms, biological group
selection and cultural group selection. Although there are differences
between the two, the essential structure of the argument is similar.
Moreover, both cultural and biological group selection arguments have
traditionally been attacked on similar grounds. As a result, although
there are differences between the two, for purposes of this brief
essay I will treat them as largely interchangeable. The analysis
presented here summarizes the more detailed arguments presented in
Todd J. Zywicki, "Was Hayek Right About Group Selection After All?"
Review of Austrian Economics 13: 81-95 (2000).
On its face, the argument in favor of group selection is highly
persuasive. Indeed, it is quite common that authors will advance a
group selection argument without being fully conscious of having done
so. Advocates of biological group selection argue that under certain
environmental conditions it may be adaptive on the individual level to
develop altruistic traits toward others. Altruism builds trust and
reciprocity, thereby reducing the transaction costs of living together
in a given society. Greater trust spurs trade, specialization, and the
growth of wealth. In turn, this allows for the maintenance of a
larger, richer, and healthier population. Such populations will tend
to prosper and spread at the expense of less robust populations,
leading to the gradual displacement of non-altruistic populations with
more altruistic, and causing the altruistic trait to spread. See Sober
and Wilson, Unto Others. Cultural group selection arguments are
similar, except that rather than propagating one's genetic traits,
natural selection operates on "memes" of rules, customs, institutions,
and norms. Groups that adopt "better" cultural practices will again
tend to grow healthier, wealthier, and more populous, gradually
supplanting less efficient cultures through conquest, migration, or
conscious adoption. See F. A. Hayek, The Fatal Conceit: The Errors of
Socialism, in The Collected Works of F. A. Hayek (W. W. Bartley, III,
ed.) (Chicago: University of Chicago Press, 1988); F. A. Hayek, Law,
Legislation and Liberty, Vol. 1: Rules and Order (Chicago: University
of Chicago Press, 1973); F. A. Hayek, "The Origins and Effects of Our
Morals: A Problem for Science," in The Essence of Hayek (C. Nishiyama
and K. R. Keube, eds.) (Chicago: University of Chicago Press, 1984);
Robert Boyd and Peter J. Richerson, Culture and the Evolutionary
Process (Chicago: University of Chicago Press, 1985).
Both biological and cultural group selection arguments have been
attacked on similar grounds. Although the development of altruistic
traits or customs is adaptive on the group level, altruism is not
adaptive on the individual level. Because altruism creates social
surplus, it is argued, any single individual would do better by acting
selfishly rather than altruistically with others. Altruists,
therefore, would share with altruists and selfish members alike,
whereas selfish members would receive these benefits but would not
share with others. Selfish members can thereby free ride on altruists.
Over time, it is argued, this would lead to selfish members of society
prospering at the expense of altruists, giving selfish individuals a
comparative advantage in propagating their genes, and causing those
with selfish traits to gradually displace altruists in the population.
Thus it is argued that a theory of group selection lacks adequate
"micro" foundations in individual reproductive activity to be a
sustainable equilibrium theory. See Richard Dawkins, The Selfish Gene
(2d ed.) (New York: Oxford University Press, 1989); V. Vanberg,
"Spontaneous Market Order and Social Rules: A Critique of F. A.
Hayek's Theory of Cultural Evolution," Economics and Philosophy 2:
75-100 (1986). For more comment on Hayek's model of cultural group
selection, see D. G. Whitman, "Hayek contra Pangloss on Evolutionary
Systems," Constitutional Political Economy 9: 45-66; G. M. Hodgson,
"Hayek's Theory of Cultural Evolution: An Evaluation in Light of
Vanberg's Critique," Economics and Philosophy 7: 67-82 (1991).
But these criticisms of group selection models overstate their
conclusion in implying that group selection is invalid a priori. Like
individual natural selection, group selection should be understood as
an empirical question, not an a priori question. For group selection
to be viable requires the satisfaction of three criteria: (1) benefit
to the group from the biological trait or cultural rule; (2) some
mechanism for intergroup competition, so that "more fit" groups can
displace "less fit" groups; and (3) some mechanism for policing
intragroup free riding. See Zywicki, "Was Hayek Right About Group
Selection After All?" supra.
First, there must be some benefit to the group from the trait or
practice. Beneficial adaptations are those that reduce transaction
costs and conflict, and thereby allow for the growth of economic
wealth and population. Hayek points to property, contract, and the
rule of law as examples of cultural adaptations that would tend to
create social benefit and thus be favored by cultural group selection.
Second, there must be some mechanism for intergroup competition to
take place. This may be through war and conquest, migration and
intermarriage, or conscious adaptation of new practices or
institutions.
Third, there must be some mechanism for policing free riding behavior
within the group to prevent some individuals from claiming social
surplus without contributing to it themselves. This suggests that the
type of altruism that would be favored by group selection would be of
the "guarded cooperation" described by reciprocal altruism. Thus, it
is doubtful that cultural group selection would tend to favor the
evolution of psychological traits or cultural practices that permitted
unconditional sharing in the social surplus. Rather, group selection
would tend to favor altruistic and cooperative behavior, but it would
tend to limit this altruism so as to prevent exploitation by
unscrupulous free riders. As noted above, it is improper to draw
normative conclusions directly from the facts of evolutionary biology.
Nonetheless, this tendency toward guarded generosity suggests that
socialism and the welfare state rest on an unsound evolutionary
foundation. By allowing free riders unlimited opportunity to tap into
social surplus, these regimes empower free riders rather than
constrain them. See Zywicki, "Was Hayek Right about Group Selection
After All?" at 90-93; Paul H. Rubin, "Group Selection and the Limits
of Altruism," Journal of ioeconomics 2(1) (Forthcoming 2000); compare
Hodgson, "Hayek's Theory of Cultural Evolution," at 79-80 (arguing
that cultural group selection leads to a mixed economy). Evolutionary
arguments further suggest that individuals may have an innate and
culturally reinforced tendency to offer charity and altruism, thereby
making compulsory provision of social services unnecessary. Moreover,
evolution suggests that voluntarily-provided social services would
tend to be provided on a local level and embedded in a network of
social connectedness and reciprocal relationships. See David T. Beito,
From Mutual Aid to the Welfare State: Fraternal Societies and Social
Services, 1890-1967 (Chapel Hill: University of North Carolina Press,
2000). By embedding the charitable relationship in this social and
reciprocal context, it is likely that this system will be more
rewarding and empowering for both the donor and donee. By contrast, it
is hard to imagine how natural selection would favor individual
preferences that are satisfied through delivery of social services
through the inefficient and rent-seeking mechanism of the modern
welfare state.
Implications for Social Sciences and Law
Throughout this essay I have attempted to interweave specific examples
of types of natural cooperation with implications for social science
and the law. It is certainly tenuous to draw specific conclusions from
the general observations of evolutionary psychology. In addition to
those presented above, this concluding section will add a few thoughts
on potential avenues of further research in law and social science.
As suggested above, there has been a recent resurgence in legal
scholarship in the concept of norms, or what was formerly know as
custom, and the law. This analysis is refreshing, in that it has
caused scholars to increasingly look beyond formal legal rules and to
the norms and practices that underlie and support legal rules.
Individual actors tend spontaneously to develop norms and customs to
solve coordination problems as they arise. Properly understood, norms
theory reminds lawyers of an earlier era where the law was generally
used to buttress and enforce these spontaneously-developed extra-legal
norms and customs. See A. C. Pritchard and Todd J. Zywicki, "Finding
the Constitution: An Economic Analysis of Tradition's Role in
Constitutional Interpretation," North Carolina Law Review 77: 409-521
(1999); Robert D. Cooter, "Structural Adjudication and the New Law
Merchant: A Model of Decentralized Law," International Review of Law &
Economics 14: 215-239 (1994).
Although important, norms theory only goes halfway. The evolution of
norms and customs can only be properly understood within a framework
that also includes evolutionary psychology. As noted, there is a huge
degree of different types of cooperation in nature that prospers
without anything like norms or institutions to enforce them.
Evolutionary psychology helps to explain why pro-social and
pro-cooperative norms tend to be more prevalent in the world than
anti-social and anti-cooperative norms. There is a certain
universality to many of the norms that are found throughout the world
and even within a given society. Assuming that it is not purely
historical accident, this tendency toward universality in the types of
norms that develop can be explained in only two ways, either as the
result of universal human nature that drives the types of norms that
will be developed, or through a system of cultural group selection
that allows good practices to drive out bad. As noted, cultural group
selection remains controversial in both the natural and social
sciences, tending to suggest that evolutionary psychology presents a
more compelling explanation. Interestingly, however, the new norms
theorists seem to be either unaware of the existence of human
universals or largely unaware of the problem of explaining these
universals. Just as norms theorists have recognized that norms lie
behind law, evolutionary psychologists have long recognized that
evolution lies behind norms.
Law would also benefit from understanding how animals generate
solutions to certain social problems. For instance, like humans,
social animals are required to deal with the potential problem of
internal conflict over scarce resources. Animals, like humans, have
devised two basic ways of preventing conflict, property rights and
hierarchy. In hierarchical relations, disputes over resources or
breeding opportunities are decided by the highest-ranked, or "alpha,"
individual in the pack or group. Subordinate individuals must obey the
will of the alpha or be punished. Although this social arrangement
tends to minimize internal social conflict (except for conflict at the
top among rivals for dominance), it also means that the resources of
all other members of the society are subject to the will of the
dominant and are subject to having those resources expropriated at any
time.
More complex societies rely less on hierarchy and more on systems of
private property, or territories, to resolve disputes. Territories
demarcate specific resources over which particular animals have
control. By marking these territories, animals can avoid constant
conflict over ownership of resources. Thus, the primary initial
impulse for recognizing property rights is to minimize social
conflict. Moreover, once property rights are recognized, it is likely
that psychological tendencies to retain and protect property rights
evolve so as encourage the holder of the property to protect it.
Animals and small children exhibit instinctive evidence of property
rights and territoriality, suggesting that the desire to claim and
protect property is hard-wired. For a fascinating discussion of the
instinctive basis of property, see Richard Pipes, Property and Freedom
(New York: Alfred A. Knopf, 1999). It seems that concepts of private
property, consensual transfer, and protection from involuntary
transfer are likely hard-wired in humans and other
cognitively-sophisticated and socially-complex creatures. This further
suggests that it is an error to see property rights allocations as
being merely conventional and subject to rearrangement at the will of
political actors. See Todd J. Zywicki, Book Review, Constitutional
Political Economy 8: 355-359 (1997) [reviewing Cass R. Sunstein, Legal
Reasoning and Political Conflict (1996)]. Allowing individuals to
plunder others' property rights and to acquire economic resources
through use of rent-seeking and political force, by contrast, can be
understood as a reversion to the political and economic structure of
hierarchy.
Evolutionary psychology also has potentially revolutionary
implications for political science. Since the publication of James Q.
Wilson's superb book The Moral Sense (New York: Free Press, 1993), a
handful of political scientists have attempted to understand the
implications of evolutionary psychology for the study of politics.
Straussian thinkers have been particularly attracted to understanding
the implications of evolutionary psychology for political behavior,
probably because of the robust view of human nature offered by
evolutionary psychology and the potential of constructing natural law
from human nature. Roger Masters was perhaps the most aggressive early
exponent of the importance of evolutionary psychology and human nature
for a proper understanding of politics and society. Beginning really
with The Nature of Politics (New Have: Yale University Press, 1989),
Masters published a series of articles and papers designed to spell
out his view of the implications of evolutionary psychology for
politics. In addition to The Nature of Politics, Masters also wrote
such interesting and provocative works as Beyond Relativism: Science
and Human Values (Hanover, N.H.: University Press of New England,
1993) and edited with Margaret Gruter the pathbreaking collection of
essays The Sense of Justice: Biological Foundations of Law (Roger D.
Masters and Margaret Gruter eds.) (Newbury Park, Calif.: Sage, 1992).
In recent years Larry Arnhart has carried forward the Darwinian
research program in political science. Building on an Aristotelian
foundation, Arnhart has explicitly advocated an evolutionary
understanding of human nature and politics. Arnhardt's exposition can
be found in his challenging book, Darwinian Natural Right: The
Biological Ethics of Human Nature (Albany, NY: State University of New
York Press, 1998). The general thrust of Darwinian-influenced
political thinking also is surveyed in Arnhardt's earlier article "The
New Darwinian Naturalism in Political Theory," American Political
Science Review 89: 389-400 (1995). Francis Fukuyama has similarly
argued for the relevance of evolutionary psychology for understanding
politics and social policy. See The Great Disruption: Human Nature and
the Reconstitution of Social Order (New York: Free Press, 1999).
A common strand in the Straussian view of evolutionary psychology and
politics is the emphasis on innate human inequality of abilities and
character as well as an Aristotelian belief in the inherently
"political" nature of man. Both of these arguments have important
implications for those interested in political science and political
theory. Contrasting with this emphasis on natural inequality is the
work of Christopher Boehm, who has stressed the concept of "reverse
dominance hierarchy" in human societies. Master and Arnhardt stress
the continuity of humans with lower animals and see humans as
exhibiting a tendency toward hierarchical social and political
relations. Boehm, by contrast, stresses the egalitarian tendency of
humans in contrast to hierarchy. Boehm is a democrat and sees human
political societies as characterized by fluid social and political
arrangements rather than rigid status hierarchies. Boehm's scholarly
output has been prodigious; most relevant for current purposes is his
most recent book, Hierarchy in the Forest: The Evolution of
Egalitarian Behavior (Cambridge, MA: Harvard University Press, 1999).
Boehm's insights have been largely untapped by political scientists,
but it seems that his emphasis on social and political egalitarianism
raises questions about the Straussian emphasis on inequality as the
basis for political society. Indeed, Boehm's insights may even be
relevant to an understanding of such mundane observations as the
public's tendencies to support anti-establishment "outsider" political
candidates such as John McCain and its attraction to populists and
political underdogs.
Finally, no discussion of the relevance of evolutionary psychology for
politics would be complete without mentioning Frans de Waal's
masterpiece Chimpanzee Politics: Power and Sex Among Apes (London:
Jonathan Cape, 1982). De Waal's extensive study of the social and
"political" relations among chimpanzees tells a Shakespearean tale of
political interactions and coalition-forming that strikingly
illustrates the political processes of primates further up the
evolutionary ladder.
The belief in the inherently "political" nature of humanity is also
open to debate. In making this argument, one must be careful to
distinguish humans' inherently political nature from humans'
inherently social nature. Although individuals are naturally social
and enthusiastic about egalitarian reciprocity-based interactions,
this type of interaction is distinct from political interactions.
There is little reason to believe that politics has anything to do
with a desire to seek "the good" or the "public good." Instead,
politics is primarily about the expropriation of wealth by politically
powerful coalitions or individuals. Thus, while individuals may be
naturally inclined to use political power to further their own ends,
it is doubtful that this sort of behavior should be encouraged.
Instead, it would seem to make more sense to try to tame this
expropriative behavior through constitutions and political
institutions designed to discourage the use of the political means of
acquiring wealth and instead channel wealth-acquisition into
positive-sum market exchange. See Mark Grady and Michael McGuire, "The
Nature of Constitutions," Journal of Bioeconomics 1(3): 227-240
(1999); Todd J. Zywicki, "The State of Nature and the Nature of the
State: A Comment on Grady and McGuire," Journal of Bioeconomics 1(3):
241-261 (1999).
The insights of evolutionary psychology also cast a powerful influence
over the study of economics. Economists generally taken personal
preferences as "given." Evolutionary psychology presents one avenue
for understanding individual preferences. Moreover, it suggests that
many such preferences, such as the desires for wealth and status, are
hard-wired predilections that are relatively unresponsive to changes
in relative prices. Of course, what qualifies as wealth or what
activities generate high social status may differ according to
different temporal and cultural forces. Nonetheless, the basic
impulses are relatively constant over time and independent of
particular social or economic contexts. This casts doubt on the belief
that preferences are primarily socially constructed and that they
therefore can be changed through the moral force of law or changes in
norms. Vernon Smith, Kevin McCabe, and other researchers at the
University of Arizona have been using the tools of experimental
economics to make predictions about individual preference functions
based on insights drawn from evolutionary psychology. All of their
work on this topic is fascinating and important. Good introductions to
their experimental approach and some of the conclusions they draw from
their research can be found in Vernon L. Smith, "Property Rights as a
Natural Order: Reciprocity, Evolutionary and Experimental
Considerations," in Who Owns the Environment? 55-80 (1998); Elizabeth
Hoffman, Kevin McCabe, and Vernon Smith, "Behavioral Foundations of
Reciprocity: Experimental Economics and Evolutionary Psychology,"
Economic Inquiry 36: 335-355 (1998); Kevin A. McCabe, et al.,
"Reciprocity, Trust, and Payoff Privacy in Extensive Form Bargaining,"
Games and Economic Behavior 24: 10-22 (1998).
In time, evolutionary psychology is likely to exert its greatest
influence in the field of economics. Evolutionary psychology
reinforces the economist's emphasis on methodological individualism
and self-interest as the foundations of analysis in the social
sciences. Thus, rather than merely assuming the primacy of
self-interest, economists can ground this postulate in human nature.
See Zywicki, "Nature of the State." In so doing, evolutionary
psychology also tends to justify the emphasis of the public choice
school on building political systems on the basis of self-interest
rather than public beneficence. Perhaps most interesting, evolutionary
psychology holds out the possibility of looking into the "black box"
of individual preferences to try to understand the structure of
consumer preferences, and in particular, why some preferences may be
more or less elastic and responsive to incentives and relative prices
than other preferences.
The two earliest expositors of examining economics through the lens of
biology were Jack Hirshleifer, see Jack Hirshleifer, "Evolutionary
Models in Economics and the Law: Cooperation versus Conflict
Strategies," Research in Law & Economics 4: 1-60 (1982); and Gordon
Tullock, see The Economics of Non-Human Societies (Tucson, AZ: Pallas
Press, 1994). In addition to Smith, McCabe, and the others at the
University of Arizona, many contemporary economists are working in the
evolutionary tradition, most notably Nobel Laureate Douglas North.
Others include Adam Gifford, see "Being and Time: On the Nature and
the Evolution of Institutions," Journal of Bioeconomics 1(2): 127-149
(1999); Hebert Gintis, Game Theory Evolving (Princeton, N.J.:
Princeton University Press, 2000); and Paul Rubin, who has written
several illuminating articles applying evolutionary psychology to
economics. This proliferation of research has coalesced into the study
of "bioeconomics" with its own society (the International Society for
Bioeconomics) and journal (the Journal of Bioeconomics). The Journal
of Bioeconomics is co-edited by Janet Landa, an economist, and Michael
T. Ghiselin, an evolutionary biologist.
Conclusion
This essay is not intended to be comprehensive. It has attempted to
state the case why those interested in law and social science should
be aware of developments in evolutionary psychology. It has also
provided a broad overview of the "four paths to cooperation" that have
been identified for understanding cooperation in nature. Finally, it
has offered some scattered thoughts on future research ideas for those
intereste
References
1. http://www.theihs.org/libertyguide/people.php/50.html
2. http://www.theihs.org/libertyguide/hsr/index.php#13-1
3. http://www.chimp-st-and.ac.uk/cultures/database.htm
4. http://www.theihs.org/libertyguide/hsr/hsr.php?id=36&print=1#_ftn1
5. http://www.theihs.org/libertyguide/hsr/hsr.php?id=36&print=1#_ftn2
6. http://www.theihs.org/libertyguide/hsr/hsr.php?id=36&print=1#_ftn3
7. http://www.theihs.org/libertyguide/hsr/hsr.php?id=36&print=1#_ftn4
8. http://www.theihs.org/libertyguide/hsr/hsr.php?id=36&print=1#_ftn5
9. http://www.theihs.org/libertyguide/hsr/hsr.php?id=36&print=1#_ftn6
10. http://www.theihs.org/libertyguide/hsr/hsr.php?id=36&print=1#_ftn7
11. http://www.theihs.org/libertyguide/hsr/hsr.php?id=36&print=1#_ftn8
12. http://www.theihs.org/libertyguide/hsr/hsr.php?id=36&print=1#_ftn9
13. http://www.theihs.org/libertyguide/hsr/hsr.php?id=36&print=1#_ftn10
More information about the paleopsych
mailing list