"selfish genes" vs. "selfish DNA"
arlin at ac.dal.ca
arlin at ac.dal.ca
Sun Feb 21 11:25:49 EST 1993
In article <1m6nlqINN6bh at shelley.u.washington.edu>, xia at hardy.u.washington.edu (Xuhua Xia) writes:
>> gene-centered view (e.g., Gould in his vicious assault on Dawkins and anyone
>> who favors his arguments, in a recent NYT Book Review).]
> Perhaps it is no a good idea to use the word "vicious". I think that Gould
> is mercyless, but not vicious.
Vicious was the wrong word, I'll admit. However, "mercyless" obscures
the point that Gould wasn't actually fair. One of the naughty things that
he did was to argue that Dawkins gave primacy to the gene-centered view in
_The Selfish Gene_, which wasn't true. Then, after setting up the naive
reader with this untruth, Gould dramatically suggests that Dawkins saw the light
and made a humiliating recantation (to the effect that the gene-centered view
did not have primacy) in _The Extended Phenotype_.
Furthermore, Gould repeatedly hinted that
there is some inner circle of evolutionary savants (either Gould is a
member of this group, or he is otherwise privy to their thoughts) that had
already thought of everything that Dawkins said, but had decided
that the idea of selfish genes wasn't worthy of seeing the light of day in
print. Then Dawkins came along and printed their cast-off ideas. This
was mean-spirited, unfair, and probably very innaccurate. Although it is
possible--even likely-- that a genetical reductionist view of the units of
selection had been vaguely considered prior to Dawkins, Gould should give
credit where it is due: Dawkins drew out the implications of this line of
thinking, provided excellent thought-provoking examples and discussion,
and presented all of this for the thinking world to evaluate in print.
If Gould or someone else would like to point out a prior source for Dawkins,
they are welcome to do so. Gould did not do this in his review.
>> adaptive explanation was not necessary. A sequence can conceivably arise and
>> spread through its own tendency to be over-replicated, whether or not it is
>> adaptive for the individual-- as long as it isn't deleterious.
> This seems to represent a misunderstanding of selfish DNA hypothesis. A
> selfish DNA element can be very deleterious to its carrier and still be
> able to spread through the population. Please read Hickey (1982, Genetics)
> and Charlesworth (1989 or 90?, Ann Rev Genetics). The only requirement is
> efficent horizontal transmission.
Right again. I should have said "as long as it isn't *very* deleterious."
Actually, it must be the case that the final judgment on an element's
ability to spread selfishly is not an absolute judgment based on a
single criterion (like your suggestion of "efficient horizontal transmission"
or my suggestion of "not very deleterious") but a relative one, right?
That is, for the selfish element to propagate, its total rate of spread has to
be greater than its total rate of loss. An element with severe
deleterious effects could still spread if it is extremely "infective"; an
element whose intrinsic rate of propagation is not particularly high
could still spread successfully as long as its effects are only slightly
> X. Xia
> Department of Genetics
> U of Washington
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