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Mohan,
That the evolution of the eye is appealed to by creationists does put discussion under a political cloud, but the puzzle remains, at least in my mind. You note that it has long been solved, and I hope that in my readings I'll encounter that solution. Until then I can only stick with the conventional criticism of functionalism in that function is a result rather than cause of development of the constituents of an organ.
I didn't realize that my reference to the evolution of flexible behavioral patterns was at all problematic. For example, humans inherit an extraordinary linguistic potential that can be expressed in a wide variety of ways though social learning. Humans also adapt to the most extreme kinds of niches. To judge from the case of the famous Alex the Parrot, parrots also have a capacity to use language similar to that of humans (but without much extrasomatic transmission). Alex can tell you when you are wrong, can pose questions, can create vocabulary and insist that you use it, etc. and so parrots could teach each other an expanded use of language, but they choose not to. Most parrots have no need to actualize this potential beyond a very elementary level. Often this inherited flexibility is called "adaptability". Perhaps I don't quite get the point of your question.
As for "emergence", this notion has evolved in unhelpful ways. According to my OED, it only means to become visible, to appear, become
known. In other words, the word roughly refers to novelties. But as radical empiricism came to prevail, it was defined in epistemological rather than ontological terms. Pepper (1926) was not the first to shift its meaning to refer only to what is unpredictable and in contrast to categorize mere novelty as unequivocally determinant. This division between ontological mechanism and epistemological unpredictability has bedeviled the discussion ever since. My perverse view is that all novel outcomes are emergent in the sense they are improbable (except in the hypothetical limiting case of closed systems) and therefore cannot be absolutely reduced to initial conditions (which is why we learn about standard deviation in school). Unpredictability is not just an artifact of ignorance, but is in principle de re natura (yes, statistical causality boils down to causality, but the issue is really one of modal realism). So I do agree that natural selection is emergent all the time, but I thought the bone of contention is often over whether environmental conditions cause the genetic distribution in a population.
At the moment I happen to be reading François Jacob, The Possible and Actual (1982) I disagree with his defining the "possible" in epistemological terms as a mental counterfactual, rather than in ontological (scientific realist) terms. He says that natural selection "does not act merely as a seive, eliminating detrimenal mutations... It integrates mutations and orders them into adaptively coherent patterns... It is natural selection that gives direction to changes." Perhaps this is what you meant regarding eye formation. In any case, I need to explore the mechanism involved here.
In my own field this issue takes the form of a debate over historicism. 19th-century historicism not only held that an explanation of a particular situation requires that it be understand as part of a greater whole (which in itself remains a causally mechanistic view), but that the history by which the whole came about has a determinative effect on the situation. In our post-modernist era, this is dismissed as "grand narrative" and "meta-theory". This objection seems right to the extent that the past (what is separated from the present in time) does not exist in the present and so can't have any causal influence in the present (our mental representations of the past, are not a reflection of the past, but a construction that is to a degree compatible with the framed traces that happen to exist in the present and are shorn of unobservables). However, there is this to be said about historicism: the effect of the past is the traces that survive into the present, and these do constrain action in the present.
In other words, Jacob seems to be pointing out that the genetic code is not intelligible simply as an isolated constraint, but to understand it we need to know how it arrived in its present condition and therefore its history. I find this unpersuasive, in that the past does not exist in the present except as a mental inference, and like a Markov process, the present is ignorant of its past.
However, it seems to me, on the contrary, that history is in fact a determinant of the present in terms of the depth of its contradictions. Another tricky word, but I take "contradiction" to be the unity and interdendence of processes that are opposite with respect to the direction of their change in probability, or as it is more commonly put, change in their entropy. Mario Bunge is one among many who pursue this line. The depth of a contradiction exists in a present as the relative probability, speed and magnitude of possible change, and this cannot be directly experienced in the present, but only known from an inference from past change. One might not find this objectionalble in epistemological terms, but as a realist, I assume that depth of contradiction is real, which is to say, makes a difference that is independent of our consciousness. In the early stage of early civilizations, there is typically greater inventiveness but not much sophistication, for it actualizes a broad probability distribution; with maturation, its inventiveness declines but it finds itself in a very sophisticated (improbable) state. This is called "locking in" in general systems theory. However, knowledge based on evidence for one moment in time, cannot convey whether the civilization is immature or mature, but one has to infer it from the degree to which the civilization historically was able to cope.
To return to your point, for "emergence" to be a useful concept, it must be explained in naturalistic terms, and whether some novelty is predictable or not is really an issue of epistemology. There is much interest in how nature gives rise to novelites that are not reducible to a prior state of affairs. To mention some popular works, David Layzer, Cosmogenesis (1990), David Bohm, Wholeness and the Implicate Order (1980), Stuart Kaufmann, Investigations (2000), Eric Chaisson, Cosmic Evolution (2001), etc. I'm not suggesting I entirely agree with these authors, but they serve to hint that a new way of representing our world seems in formation.
You bring up evo-devo. If this is taken to mean that genes are constantly being reconstructed, I didn't realize it was a controversial issue. I'll do some reading on evo-devo, Richard Goodwin and Sean Carroll. I get the feeling that Goodwin may be hung up on the dynamics of far-from-equilibrium systems involving negative and postive feedback to give rise to extraordinary trajectories, and, if so, I might find myself a bit critical (I've never understood the point of chaos theory, and I distance myself from general systems theory to the extent it implies closed systems). But you have pointed me in the direction of some useful reading, and I thank you.
On your characterization of the Baldwin Effect, what it seems to amount to, to put it in the language of the philosophy of causality, is that we can't infer a causal relation between regularly proximate events because both may be effects of a different cause (what Wesley Salmon calls pseudo-causality in The Causal Structure of the World, among many others who discusses this point). If so, then you are right that it is not what I'm looking for.
But I also hesitate to characerize what I am looking for as support for Lamarckianism, given the undertainty of its definition. Jean Marx: a change acquired in response to an altered environment becomes hereditary. Gordon Kaplan: the essence of Lamarckianism is often imprecisely summarized as the inheritance of acquired characteristics, the stable inheritance of adaptive changes induced in an individual organism by an altered environment. Pietro Corsi: (I've not read his book) Lamarck felt that change in circumstance induces change in habits and thence change in form. It strikes me that the ambiguity of a) environment causing change in an individual's genes through some yet unknown mechanism, b) individual adaptation of organism and its environment causes change in that individual's genes, c) the habitus or behavior of the individual, regardless of whether it is adaptively advantageous, brings about that change. So is Lamarckianism addressing behavior in general, only adaptive behavior, or merely circumstance as a causal factor?
But it strikes me that the basic issue here is really over the unit of selection. Lamarckianism seems to imply an individual organism, but the neo-Darwinian synthesis sees population as the unit. In the latter, it seems one can legitimately speak of population genetic change as an effect of adaptation. However, the issue remains that reproductive sucess may have other determinants, such as income, or China's one-child policy, or geographic distribution. Then genetic drift would not simply reduce to relative environmental adaptability. That the economy is ultimately determinant means that it is the ultimate souce of all possibilities, not that it is mechanistically causal for all aspects of life. Do you think I am right to infer that the basic issue is over the unit of selection? If the unit of the individual organism happens to be the focus, I suspect the question boils down to the influence of behavior, and to suggest that individual behavior (short of exposing oneself to dangerous radiation, etc.) can affect genetic structure seems a big stretch.
But assumed here so far is a static individual. In fact the individual is a process that originated from cell reproduction and continues to replace cells, and so my original question was whether this reproduction within the individual's life span might not be subject to internal selective constraints that have nothing to do with the environment or adaptation to maximize metabolism? If this is so, are then the sperm and ovum also subject to such constraints? (my ignorance) If so, the genetic code passed on to descendents can be affected by intrinsic constraints. Whether such intrinsic constraint can be stretched to include learned behavior, though, seems a bit much (such as behavior spawning a protein that somehow finds it way to block gene expression in the reproduction of spem or ovum cells).
Haines
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