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I thought the list might benefit from this piece of an essay of my
father's. It's relatively short (9 paragraphs), at the end of Chapter 21 in
Essays on Life, Itself (Essay: Cooperation and Chimera), but in the event it
gets bounced by Tim's list server, I hope Tim will be able to post it on my
behalf.
Robert Rosen wrote:
"Adaptation is a meaningless concept unless it is tied to an
individual whose survival is enhanced by it. Otherwise, it just disappears into
dynamics. If we choose our individuals differently (and correspondingly change
our idea of what survival means), our notions of what is adaptive will generally
change as well.
From the outset, we have tied our identification of an
individual to its genome, and hence with the formal causes of its behaviors. A
behavior itself could be adaptive or not, in this context, depending on its
effect on genome preservation. In this context, then, the fittest behaviors are
those that minimize change of genome (identity) in the face of environments that
can change it. I have given some very general conditions for the fitness of
chimera formation (e.g., cooperation) in this situation [using the example of a
hermit crab+shell+anemones and other living camouflage attached to the shell by
the hermit crab].
In general, one of the basic requirements for identifying the
kinds of individuals to which such arguments apply is that they themselves must
not, by virtue of their own behaviors, be able to change their own
genomes. That is, we must not allow their behaviors to act back on their own
formal causes. This is true quite generally; in biology, it is the content of
the Central Dogma (Judson 1979).
However, behaviors do affect the ploidy of genome, seen in the
context of a population. Such a population may itself be regarded as a new
individual, whose behaviors can be regarded as adaptive or not. This is the
context of evolutionary adaptation. In this new context, adaptations
are measured by the growth of ploidies.
At heart, the Darwinian concept of survival of the fittest
rests on an identification between the two entirely different kinds of fitness
of individual behaviors I have just sketched, pertaining to two entirely
different kinds of individuals, and hence two entirely different measures of
survival and adaptation. Conceptual difficulties with evolution have always
grown from the fact that the two need not coincide.
In particular, there is no reason why behaviors that maximize
the survival of an individual should also maximize its fecundity, or indeed vice
versa. To the extent that these entirely different measures of fitness diverge,
to speak of fitness as an abstract property of an individual behavior simply
creates an equivocation. Especially so since fecundity arises from individual
behaviors that may be very far from adaptive in the sense of individual survival
[think male Black Widow spider...]. Equivocations of this kind spawn apparent
paradoxes. A simple example is the so-called Galileo paradox, which involved the
"size" (i.e., cardinality) of sets. Galileo asked which is bigger: the set of
all integers or the set of even integers. Judged simply by inclusion, and
according to the Euclidean axiom that a whole (all the integers) is bigger than
any proper part (the even integers), we conclude that the former is clearly
bigger. But, as measured by enumeration, we must conclude that the two are the
same size.Two entirely different measures of size are involved here: measures
that coincide for finite things but that can disagree for infinite ones. Indeed,
the Galileo paradox ended, in the hands of Georg Kantor, as the diagnostic
property that separated what is finite from what is not.
So it is with concepts such as fitness, and especially so when
we attempt to compare fitnesses. Here we treat a chimera as a new individual and
ask about its fitness as such. Moreover, just as in the Galileo paradox, we try
to compare its fitness with those of other individuals, especially against those
of its constituents, in terms of the advantages of cooperation against
noncooperation.
What I have tried to do in this discussion is rather more
modest. I have tried to argue that chimera formation culminates in the
generation of new kinds of individuals; it causes new identities, new genomes,
and new behaviors to emerge, which could never be generated in any other way,
and certainly not by processes of differentiation alone. I have tried to give
conditions under which chimera formation is adaptive, in the sense that it
favors the survival of its constituents more than the survivals they could
achieve otherwise. But I certainly cannot say that, if fitness is measured in
terms of ploidies, as it is when we speak of Darwinian evolution, such
considerations have any significance at all. The two issues are clearly not the
same. Indeed, an establishment of relations between these two distinct
playgrounds for adaptiveness, the evolutionary and the physiological, would in
itself be an instance of chimera formation."
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