Anon. wrote:
> Guy Hoelzer wrote:
>>
>>If I read your question correctly, you are asking whether anybody thinks
>>that natural selection at the level of the gene has significant effects in
>>biological evolution.  The answer is clearly YES.  Many evolutionary
>>biologists think that this is the primary level at which biological
>>selection happens.  Dawkins is an extremist and a leading voice in this
>>crowd.  For example, he refers to individuals as
"vehicles", and suggests
>>that they are merely convenient constructions by genes, which are used to
>>promote the selfish interests of the genes.  

Sexually reproducing organisms, in particular, are not replicators since
what they "reproduce" are far from exact copies of themselves.  On the
other hand, genes can remain relatively constant over generations, although
even here phenotypic effects of a gene can vary depending on the
particular combinations of other genes in the vehicle.  I suspect this
more than anything is why organisms are referred to as vehicles rather
than replicators.

>>This view is inconsistent with
>>multilevel selection theory, which is in my view the essence of contemporary
>>selection theory and provides a more balanced and logical perspective on
>>natural selection.
>>

Folks like Williams, Dawkins, Smith, Hamilton, Price, etc. have no problem
with multilevel selection theory.  Its just that, according to most of the formal
models, its influence should be sufficiently weak to be almost negligible
on most occasions:


     This book (Wilson and Sober's 'Unto Others') should carry a
     health warning.  Read critically, it will stimulate thought
     about important questions.  Swallowed whole its effects would
     be disasterous (Maynard Smith).


Given this fact, there is a danger that folks will want to invoke higher
levels of selection to countenance observable features in nature that
often appear to have been group selected, but which the models simply
can not currently accomodate (e.g., 9/11 terrorists, rescue workers, etc.).
IOW, group selection offers an easy way out, but not all the problems in
science have an easy way out.  Sometimes they might even require looking
about for hidden assumptions that lie just below the surface that are
making one's theory appear to be in err (e.g., the assumption that
rational creatures can be safely relied upon to maximize their own
long range self-interest without eventually coming to require some
sort of justification, i.e., needs for love, attention, romance, religion,
autonomy, justice, purpose, meaning, moral integrity, power, wealth,
bing viewed as the smartest contributor to a newsgroup, etc.).

   "Terrorism is the result of poverty.  Not a poverty of material
    things, but a poverty of dignity" (Egyptian philosopher)

   "Give me liberty or give me death" (Nathan Hale)

> 
> I've not read any Dawkins for a few years, so I wouldn't want to comment 
> on what he himself believes, but I disagree that the idea of vehicles is 
> inconsistent with multilevel selection, all it means is that there are 
> different levels of vehices - ferries carrying cars if you will 
> (incidentally, Hamilton was one of the first to derive a model with 
> these ideas in them).  Someone mentioned Laurent Keller's book, and he 
> deals with this in the introduction - basically pointing out that the 
> problem is solved, and we should get on with dealing with more 
> interesting questions (like those in the rest of the book).
> 

Agreed.  The problem which is NOT solved, however, unless one buys into
some variation on the theme of group selection, is that same old "central
theoretical problem of sociobiology" (Willson) that's been with us from the
start, i.e., ye old altruism problem (biological altruism, that is,
altruism that can not be accomodated under the banner of inclusive fitness).

While the formal models developed by Hamilton, Smith, Price, et al
have done a marvelous job of accomodating altruistic anomalies in
NON-HUMAN SPECIES, most of the behavior in man is still far from
explained, and which was what I thought this thread was supposed to
be about (i.e., the role of cognition in usurping some of the older
mechanics of natural selection).  Indeed, if anything, the formal
models have only served to deepen the mystery, so much so as to
require a full fledged addendum to the theory of natural selection
(memetics), as Dawkins makes clear in his last chapter in 'The
Selfish Gene':

   As an enthusiastic Darwinian, I have been dissatisfied with
   explanations which my fellow-enthusiasts have offered for
   human behaviour.  They have tried to look for 'biological
   advantages' in various attributes of human civilization.  For
   instance, tribla religion has been seen as a mechanisms for
   solidifying group identity, valuable for a pack-hunting
   species whose individuals rely on cooperation to catch large
   and fast prey.  Frequetnly the evolutionary preconception in
   terms of which such theories are framed is implicitly group-
   selectionist, but it is possible to rephrase the theories
   in terms of orthodox gene selection.  Man may well have
   spent large portions of the last sseveral million years
   living in small kin groups.  Kin selectio and selection in
   favour of reciprocal altruism may have acted on human genes
   to produce many of our basic psychological attributes and
   tendencies.  These ideas are plausible as far as they go,
   but I find they do not begin to square up to the formidable
   challenge of explaining culture, cultural evolution, and the
   immense differences between human cultures around the world,
   from the utter selfishness of the Ik of Uganda, as described
   by Colin Turnbull, to the gental altruism of Margaret Mead's
   Arapesh.

   I think we have got to start again and go right
   back to first principles.  The argument I shall advance,
   surprising as it may seem coming from the author of the
   earlier chapters, is that, for an understanding of the
   evolution of modern man, we must begin by throwing out the
   gene as the sole basis of our ideas on evolution.  I am an
   enthusiastic Darwinian, but I think Darwinism is too big a
   theory to be donfined to the narrow context of the gene.  The
   gene will enter my thesis as an analogy, nothing more.
   (Richard Dawkins, The Selfish Gene, p. 205).



PR
---
þ RIMEGate(tm)/RGXPost V1.14 at BBSWORLD * Info{at}bbsworld.com

---
 * RIMEGate(tm)V10.2áÿ* RelayNet(tm) NNTP Gateway * MoonDog BBS
 * RgateImp.MoonDog.BBS at 9/24/03 11:56:26 AM