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Farewell to Darwin! |
This kind of approach could be termed "anything goes"; the biologist offers adaptations for sale like a car dealer produces second-hand cars. The whole thing functions much the same as thousand years of scholastic "proof" of the virginity of Holy Mary; as an edge-stone for arguing reason. Parallel to this there is another, more conventional, matter-of-fact approach as well, and it's only here that applied Darwinism becomes really primitive and outdated. The second type of approach is represented by Gareth Jones (1987): Selection against large size in the Sand Martin Riparia riparia during a dramatic population crash. Ibis 129: 274 - 280. In short the conclusion of this paper goes: There was a significant reduction - amounting to 0.25 mm = 1.3 % (my comment) - in the mean keel-length of Sand Martins captured at the main study colony in 1984 compared with individuals measured in both 1982 and 1983, suggesting that selection for small body-size had occurred during the period of high overwinter mortality. Here is instant magic with a tangible effect! Luckily, Jones balances his selection against large size with selection in favour of large size (during the breeding season) in his discussion, so the outcome of the whole selection business probably amounts to nothing - in spite of the "promising" title. The selection per se may be indisputable, but permanent adaptations are not achieved in this way, what we see here is a nonsense "jerk".
The Emlen/Demong and Hoogland/Sherman papers take the bull by the horns: they go for adaptation without appointing any plausible selective mechanism. (Such a mechanism would immediately dissolve in the contradictory gap between the two papers.) The problem of Jones is the inverse, he has selection but no obvious adaptive significance - when his perspective is expanded from winter to full annual cycle (and this expansion is always problematic to Darwinism). In both cases the result of the Darwinist approach is status quo: species are already adapted and selection seems to be unnecessary, somewhat of a drag - or species are selected, but the net result is of doubtful value when confronted with actual needs, as perceptible to the human eye.
There are thousands (or, more likely: tens of thousands) of papers of this kind, many almost shocking in their single-legged approach, their way of locking the studied animal into a hermetic box, isolating it from disturbing subsidiary influences and consecutive events, finally holding it out as illustration of dramatic "selection" or some tautologically worded "adaptation". The peculiar, expectant character of Darwinism becomes manifest: to begin with an event of some kind must occur, this event brings about selection, and the selected population is held out as if "adapted" to changed conditions. It must be emphasized: in the context of Darwinism (or Neo-Darwinism; particularly where individual selection is the point of departure) practically every structured event may be construed as an adaptation - still, in most cases it is barely made probable, or it is not made probable that the Darwinist version of "adaptation" is at the core of events. And least of all has anything been revealed about the true, underlying occurrence, particularly if there is an active, creative element: niche expansion, acquisition of properties. The best thing is to remain silent ninety-nine times out of a hundred when the compromised concept is proffered, then it should be permissible to speak about a certain "expediency" in the hundredth case.
In view of this regiment, this rectifying pressure, it is a little surprising to note, that there are a few prominent ecologists from the second half of the 20th century, who have avoided making significant personal contributions to Darwinist theory. Robert May for one will quote from orthodox reasoning, but the former theoretical physicist remains oddly passive and non-committal when it comes to making contributions of his own in this context. Unlike e.g. Richard Lewontin, who is always discussing Darwinism with the face of a well-meaning reformer trying to expand it into meaningfulness. The most important reformer (working within the scope of Darwinism, loyal to its original impetus) - and to some extent, critic - comes from the other side of the Atlantic, however: the British geneticist C. H. Waddington, editor of three volumes "Towards a Theoretical Biology" between 1969 - 71. A truly utopian and highly deliberate title, contrasting with May's self-conscious and not fully justified 1976 title "Theoretical Ecology"! Waddington attains a particularly fundamental critical position relative to Darwinism when he adds the French mathematician (topology) and philosopher René Thom to his "crew"; Thom has nothing of the biologist's characteristically half-hearted, anxious criticism of the own episteme, he overtly declares that biology has run into a blind alley and that Darwin is an Emperor without clothes. His general position is clear from an introduction to the article "Darwin cent ans après", printed in Rivista di Biologia 1983:
I belong to those, who have never ceased to be surprised at the enormous fame (gloire) of Darwin. Considering the fact that evolution theory is in practice the one and only theory embraced by biologists, and that its proper deductive contents are practically nil, a correct idea may be attained of the fundamental incompatibility that prevails between biological thinking and theory. And still, this was not always so: already Aristotle launched a program for a basically comparative biology ( a "moriology", in the words of Pierre Pellegrin); later on, between 1780 and 1840, there was in the German Naturphilosophie and the French School of Anatomy an enormous prospering of ideas (I would like to call these thinkers the "Pre-Socratics of biology"). Among all misdeeds resting on the conscience of Darwinism, one is the fact that it put a radical end to this speculative boom, instead favouring almost completely tautologous (and in addition often suspect) contemplations of adaptation.
Waddington has an idea, a guiding thought: he wants to replace predetermined purpose with something less precise: a "road". This road does not have the goal, telos, in view, instead its principal aim is to stabilize a development, an evolution, keeping it on track, preventing it from driving into the ditch or ending up in total nothingness. Such a "road" he terms a chreod. Thom translates this into the well-known attractor concept from dynamics (an area of low potential, a singular point, a basin, a valley in a surrounding of higher potential), and furthermore introduces an agent responsible for the transitions from one dynamically stable regime (an attractor, a chreod) to another: the dynamic catastrophe. This is his proper achievement in the context of biology: he rejects any notion of more sophisticated "instruction" from the level of the genome to processes at different levels, arguing that cells do not offer a sufficiently stable environment for such a decoding; errors would be omnipresent. His own bid is structural stability as the one and only thing to be guaranteed at all levels: cells, organs, organisms, populations. Processes (with inevitable parameter variations) should be kept within acceptable limits by constraining attractors, while catastrophes stage the radical, trend-breaking course changes. A process of this kind could be termed teleonomic, it contents itself with "naming" the goal, or mentioning that it is heading for some kind of unspecified goal (the difference relative to teleological thinking may seem subtle, but it is there). The outcome will differ from any originally envisaged telos; experiences from the road will influence the result, so the goal is not determined by a fixed telos. Instead the whole thing adds up to a regulatory approach, incorporating elements met with on the road, facilitating negative and positive feedback (which adds to structural stability). In view of this relative openness to an environment the Waddinton/Thom way of approaching the problems of development/evolution is more rewarding from a modern standpoint, while Darwin's attempt seems irretrievably lost to eighteenth century thought in its barren, antithetic opposition to an outdated teleologic thinking, coloured by religion.
In a series of articles on Sand Martins, based on material from SW Scania, I will try to avoid adaptive terminology, to begin with this will be noticeable as a void in the text. (I do not contest the need for true adaptation, but I argue that it is in most cases of ad hoc character, and would be only injurious if it were to be made permanent by means of some sort of biological program). The void is of a temporary nature, however; somewhere down the road I will interpose a paper with theory and new concepts, these will be worked into the first articles as well. The time-scale of the whole project is 2 - 3 years.