| This article
was originally published in the Guardian,
December 18, 2003; used here with permission.
The Unselfish
Gene
by Johnjoe McFadden
What prompted Good
King Wenceslas to look out on that feast of Stephen? And why should
he have cared that the poor man was gathering winter fuel? Modern
evolutionary theory agrees with market economics that we are inherently
selfish and unlikely to give if we don't expect to receive. But new
research challenges that model.
The origin of altruism goes to the
heart of the gene/culture debate that was launched in 1975 with
the publication of EO Wilson's Sociobiology
and, a year later, Richard
Dawkins' The
Selfish Gene.
Sociobiology claims that human nature – and by extension
human society – is
rooted in our genes: we are, according to Dawkins, "lumbering
robots" created "body
and mind" by selfish genes. This is anathema to social scientists
and biologists such as Steven Rose, who see human nature as far
more malleable.
Altruism is not confined to humans,
but when animals give presents
it is nearly always to close kin. The mathematical biologist
JBS Haldane is credited with discovering the mechanism known as
kin
selection, when he declared that he would lay down his life for
two brothers
or eight cousins. Haldane's familial benevolence was based on
the fact that two of his brothers or eight of his cousins would
carry
just about all his genes. So helping your relatives ensures that
your (shared) genes live on.
Kin selection may account for pack
behaviour, but it fails to account for human benevolence, which
is often extended well beyond
the
family. It is not only Blanche DuBois who can depend on the
kindness of strangers.
Codes of hospitality are a common feature of human societies – from
the desert-dwelling Bedouin to the Arctic Inuit.
To explain
non-kin-directed altruism, an assortment of gene-based mechanisms
has been proposed, ranging from reciprocal altruism
(you scratch my back and I'll scratch yours) to signalling
theory (conspicuous
kindness to attract mates). But none can fully explain human
generosity. What did Good King W hope to gain from bringing
flesh and wine
when the frost was so cruel outside? He could hardly have
expected the
poor man to reciprocate. And tramping about in all that crisp
and even snow was unlikely to improve his mating options.
Kindness
and cooperation underpin much of human society. From the Kyoto
agreement to arms controls or the state of
public
toilets, they all depend on individual willingness to commit
resources
to
a common good. But no one has come up with a satisfactory
evolutionary explanation of why we do it.
In a recent Nature
paper, Ernst Fehr and Urs Fischbacher of the University of Zurich
evaluated the evidence from
a series
of
cunning experiments.
In the ultimatum game, two subjects are asked to share
a pot of money, say £100. One of them (we'll call
him Steven) decides the cut - who gets what. The other
(we'll call him Richard) can either accept
his share or cry foul, in which case neither of them
takes any of the money away.
The players play only once
so there isn't an opportunity
for reciprocal altruism. If Richard is behaving entirely
selfishly
(programmed
by his selfish genes), he should accept whatever Steven
is prepared to give. But generally he doesn't. If Steven
donates
less than £25,
Richard generally refuses his share and they both leave
the table empty-handed. Richard is prepared to forsake
his (albeit smaller)
share in order to punish Steven's selfishness.
Another
experiment looks at public-good altruism. Here a
group of subjects are each given a sum, say £10,
which they can either keep for themselves or pay
some amount – a tax – towards the public
good. The taxman (we'll call him Gordon) is generous
enough to double the tax revenue and give an equal
share back to each member of the
group, whether or not they paid into the tax kitty.
It makes sense for the group to donate everything
to Gordon who doubles and redistributes
it. But instead of getting £20, the group members
discover they only take away £12 or £15.
Someone's not paying his or her share of the tax
but still claiming the reward. At the
next round, knowledge that some neighbours are freeloaders
prompts group members to reduce the tax they are
prepared to pay. The process
of cooperation decay continues until nobody is prepared
to pay anything.
Avoiding cooperation decay is the
aim of governments and international institutions.
Fehr and Fischbacher
claim
that the key to promote
what they call strong reciprocity is rewarding
generosity with kindness but punishing cheaters, even at the
expense of the
punisher. This
is why Richard refused to accept Steven's offer,
though his genes might have been telling him to
take the money
and run.
Similarly,
if public-goods experiments allow subjects to punish
cheats (even if the punishment is costly for the
punisher), cooperation
flourishes.
Strong reciprocity promotes kindness
and discourages cheats, but is it a product of our genes or in
our culture? It
can't be entirely
genetic, since different human societies (with
very similar genes) vary greatly in their tolerance
of
cheating. Fehr
and Fischbacher
argue for gene-culture co-evolution: cultural
and institutional environments promote social norms
that favour the selection
of genes that promote
cooperation.
Making strong reciprocity work at
both a local level (discouraging anti-social behaviour) and
international
level (persuading
the Americans to sign the Kyoto agreement)
would be beneficial to
society and the
world. And I for one feel much happier singing
Good King Wenceslas's praises when I know he
wasn't just
a lumbering
robot, the slave
of his selfish genes.
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