Only recently I became aware of the
fight that occurred earlier this year between two of my heroes:
Edward O. Wilson and Richard Dawkins. Wilson
at 84 (!) years published yet another book entitled "The Social
Conquest of Earth" that, besides the sociobiology of ants, bees
and termites, deals with the sociobiology of man. Wilson used to be
an advocate of kin selection whereas Dawkins is the advocate of gene
selection. According to the review that Dawkins wrote in Prospect
(See
here), Wilson finally has agreed kin selection can be explained
by gene selection and now steps into the trap of Richards enemy
number one: group selection. Now that is interesting to me since
Dawkins refutes group selection religiously and I want to at least
study what group selection might have to offer for what I refer to as
"Darwinian Ascension". Maybe Dawkins would initially see
this as a kick in his crotch so let me be clarify a bit: My interest
in group selection regards Cultural rather than Biological Evolution.
Can we ascend the power of our genes by using our memes? I believe
Dawkins might share my interest.
So what is this row about? Pwf, that
is not so easy to explain since it involves a lot of detail. See also
the seemingly endless discussion that follows Dawkins' review and
Wilsons' reply. It has some interesting details but it quickly ends
in a discussion regarding memes rather than group selection in
Biological Evolution, the point Wilson wants to make in his book.
Unfortunately it does mean that this particular blog contains a lot
of jargon, which I would normally explain but which in this case
would interfere with the blog itself. I will however put some links
for background information.
Basically, Dawkins, although in my
opinion correct, has put himself in an awkward situation with his
book "The
Selfish Gene". There he lay the basis for his theory that,
to put it simply, states that the only real unit of selection is the
gene since the gene is the only entity that really replicates itself.
Why does that put Dawkins in an awkward situation? Because it is a
very reductionist position and most people hate reductionism since
they do not clearly understand it and there is still a lot of Greedy
Reductionism. It is easy just to skip a few facts. Furthermore
the fact that a reduccionist believes he can reduce everything does
not mean he can do it today. It is just a "belief" that in
the end there is no real reason to come up with something additional,
a Deus ex Machina or a Skyhook. And that is exactly the point of
Dawkins. Gene selection CAN explain for all other apparent levels of
selection such as the individual, the family (kin) and the group. So
why come up with a Skyhook such as Groups Selection? You might argue
that asexual organisms also replicate itself, hence reduction to the
gene is not always feasible. Here I argue that sex, although
extremely costly (you need to maintain half of your genetic material
apparently for no reason), is the winning emergent property of
evolution that allows for flexibility. Please do take into account
that it is not the strongest, fastest or tallest organism that wins
the struggle for existence, it is the one that can adapt. For this
reason we have sex. Asexual organisms likely obtain certain levels to
adapt by allowing for high levels of horizontal gene transfer and
higher rates of mutation. Recent molecular evolution theories
regarding early evolution describe a communal evolution of genes.
Microorganims (read asexual organisms) share their genes by means of
horizontal gene transfer, a mode of living guided by the optimization
of the genetic code (See for instance PNAS
103:10696 or or TIBS
24:241). Hence, again the only entity that really replicates
itself is the gene so only the gene can be subject of selection.
In "The Selfish Gene" and
some of his follow-up books such as "The
Extended Phenotype", Richard makes really clear that his
theory is conceptually very strong. To me it is all just so obvious
that I do not easily understand why people do not see the point,
which unfortunately happens too often. The point is: You can explain
ALL aspects of Evolution with a gene centered view but not the
other way around. So why stick to other theories? I do not state
we should discard them, it is just that there is no evidence NOR are
there indications. But I do keep it in mind. Look at what happened to
Lamarcks' theory of inheritance
of acquired characters. Until a number of years ago the theory
was seen as utterly ridiculous but has clearly revived on the basis
op epigenetics.
The only answer I have in order to
explain the resilience of many scientists against the gene-centered
vision, is that there has to be something else that makes life. Where
does the spark of life come from? Obviously not just a valid
question, no I would concur with Shakespeare, albeit with a slight
twist: "To be or not to be, that is the question". I say:
Somehow complexity makes the Spark of Life and it is the job of
Scientists to find out how. Others say it is God and the majority of
people with a proper education in Science will say "We will,
most likely, never find out". So in the end this is about where
do you stand in life: Are you religious, agnostic or atheist.
Needless to say that Dawkins is an Atheist and Wilson an Agnostic.
Just to clarify: I do not mean to reduce any argument or discussion
to the indicated level of "Where do you stand in life", I
only want to indicate that it might very well have a strong influence
in the way people, among which you and me, think. Are these Memes?
Back to the battlefield. Basically, it
deals with the apparent incapacity of Hamiltons' rule in explaining a
number of aspects in Evolution. Wilson, backed up by two very capable
biological Mathematicians, explained in a Nature paper in 2010 (Free
access paper provided by NIH), that Hamiltons'
rule CANnot explain for it all. Not being a Mathematician, I
understood the paper such as in "Math can only give you the
correct answer as far as the model is correct but on the other hand
the model can only give you the correct answer as far as the data are
correct". Problem here is likely our understanding of the term
"fitness". Can we really calculate the fitness a gene has
for an individual, or worse for a group? Most certainly not. Hence I
always understood Hamiltons' rule as a conceptual one rather than
believing I can use the formula with accuracy. A similar thing has
happened to Wrights' connected theories of fitness
landscapes and shifting
balance. Fisher always came with calculations and claimed that
populations were actually quite big. But that is so beside the point
Wright wanted to make: Wright made it conceptually plausible to
arrive at a higher fitness peak, even when that means passing through
a fitness valley. He even clarified that effective population size
determines whether the process will actually occur or not. But as
fitness, effective population size is virtually impossible to
calculate. The same goes for Hamiltons' rule. It is very unlikely
that math will really demonstrate who is right since calculating
fitness is a sheer impossibility. Moreover, what really strikes me
most is that people that fear reductionism, have such problems with
conceptual explanations and go for a kill by means of mathematics,
reductionism to the max. Group selection as an independent mechanism
does not make any biological sense since there will always be one to
exploit the situation rendering the "evolutionary strategy"
instable. And I still have not heard one decent argument against gene
selection. And NO, too reductionist is a terrible argument, gene
selection is not gene centered: As if the theory does not take the
environment into account. A good gene does well in a certain
environment, that is actually the core of Dawkins' thinking.
Then am I sure there is no thing such
as group Selection? That is like asking: Are you sure there is no
teapot orbiting the sun somewhere (Russell)? Of course I am not sure
but providing "mathematical evidence" for your belief that
there is more than just gene selection is simply not the scientific
way. Explain me why, how and what is the reason for the phenomenon.
Let's put it differently. The concept of a meme is derived from a
gene. Memes are subject to group selection, although it is often
broken. The difference here is that it will not have a large impact
on fitness. Hence, actually we all know that group selection is
likely to occur also at a biological level BUT that the impact on an
evolutionary timescale will be very limited. My belief is that group
selection requires a force or reason to become established. In
cultural evolution that would be intellect and free will. So show me
the force that might drive group selection at a biological level and
I will take it seriously.
May the force be with you!
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