Why bother being concerned for others?
The theory of inclusive fitness
has been favoured by evolutionary
biologists for almost 50 years. The theory resolves
why people behave selflessly by considering
the genetic relationship between
the helper and the helped individual. Altruism,
the unselfish concern for the welfare
of others, evolves if the cost to the helper
is less than the benefit to the recipient and
is weighted by the genetic relatedness between
the helper and the recipient. The
more genes shared, the more help provided,
which leads to an increase in the probablility
of the helper’s genes getting passed onto the
next generation. A neat summary of the theory
is given by British evolutionary biologist
J.B.S. Haldane, who said “I’d lay down my life
for two brothers or eight cousins.”
Last August, mathematical biologist Martin
Nowak and two Harvard colleagues argued
in a controversial article in Nature that
predictions from inclusive fitness have highly
limited applicability and only work under
very strict conditions.
This sent inclusive fitness right back into
the centre of debate in the evolutionary biology
community. Nature later published five
fiercely critical responses to the paper, including
one signed by 137 (!) researchers.
Critics focused on the particular claim that
inclusive fitness theory has contributed nothing
to our understanding of social evolution.
“This claim is just patently wrong”, commented
Andy Gardner of Oxford University
in an interview in the New York Times. Jerry
Coyne from University of Chicago went
further in his blog, Why Evolution is True,
where he commented that Nowak and his
colleagues demonstrated a “wilful ignorance
of the literature.” Gardner, Coyne and others
point to fruitful empirical studies such as
parent-offspring conflict.
In Nowak’s book, Super Cooperators:
Altruism, Evolution and Why We Need
Each Other to Succeed written together
with New Scientist editor Roger Highfield,
he explains his reasoning to the general
public. The book is an exciting account of
how mathematics has enhanced the study
of all sorts of biological questions, including
the spread of cancer, the evolution of
language, and the occurrence of altruism
in the living world.
Nowak outlines five rules for the evolution
of cooperation: direct reciprocity (being
nice to individuals that are nice to you),
indirect reciprocity (having a reputation
of being nice makes others more likely to
be nice to you), spatial games (be nice to
your neighbour), group selection (cooperating
groups do better than non-cooperating
groups) and kin selection (Nowak agrees
that giving preferential treatment to relatives
can work under some circumstances).
The statistician George Pox once commented
that “all models are wrong but some
are useful” and that holds equally true today.
The relative importance of the five rules will
be the subject of much future debate. However,
one problem Nowak overlooks is the
fact that inclusive fitness theory is not just
a tool used to calculate when social traits
are likely to evolve, but also tells us something
very fundamental to the question of
what natural selection maximizes: inclusive,
rather than individual or group, fitness. Before
Nowak addresses this shortcoming, he
will struggle to convince the scientific community
of the value of his models, however
elegant they may be.
Overall, SuperCooperators is the kind of
book more scientists should write. It provides
a personal account of one of the most
controversial topics of biology and manages
to do so in a very accessible way. Add
in some personal anecdotes about playing
soccer with members of the House of Lords,
cracking mathematical problems when hiking
the Alps, and sipping cocktails with a
Wall Street tycoon — and you got all the ingredients
of a bestseller.
