Saturday, August 8, 2009

NOTES: Evolution (ed.) A. C. Fabian

Evolution, (ed.) A. C. Fabian (Cambridge, 1998)

p. 4 In this work, I try to identify adaptation as the most distinctly anglophonic subject of natural history and subsequent evolutionary ideas.

7 Darwin's revolution may be defined by its radically new and utterly inverted explanation of adaptation, but not by a decision to make the subject central……for good design had been the primary subject of English natural history for at least 200 years.

9 We will best understand the truly revolutionary aspects of natural selection when we can map its explanatory inversion upon the unaltered conviction that adaptation represents the central phenomenon requiring explanation by any adequate theory of life's history.

17 Critics would not object so strongly to adaptationist arguments as invariable first approaches if falsification of a particular claim could lead to tests of truly different alternatives outside the adaptationist programme. But the committed [18] functionalist does not work in so open a manner, and disproof of one adaptationist hypothesis leads only to lateral feinting towards a different story.

23 …adaptation need not be the fundamental result of life's transmutational history. Perhaps the continental perspective is more correct, and most adaptations rank as subsequent, particularistic modifications of underlying structures and as products of their transformational rules and regularities.

This forum is not the place for an extensive compendium, or a long defence, of these alternatives. (As an agnostic on this issue, I would not even be comfortable in presenting such a defence, nor can we fairly depict the issue in such a dichotomous manner at all.) But I do think that a variety of structuralist approaches are now in the ascendancy, thus giving new life to an old division that goes back to the pre-revolutionary version of Geoffroy Saint-Hilaire touting the power of archetypes and laws of form against the non-evolutionary [24] adaptationism of Georges Cuvier in their famous debates of 1830 at the Académie des Sciences in Paris. D'Arcy Thompson kept the structuralist vision alive, with an explicitly anti-Darwinian evolutionary version, in the finest work of prose in English natural history––On Growth and Form. This decade, Stuart Kauffman and Brian Goodwin have both written powerful and provocative, if flawed, modern versions that explore sources of biological order arising from structural rules rather than functional selection. (Kauffman, in particular, has underlined the potentially non-oppositional status of structuralism to Darwinian functionalism, pointing out that his laws of form provide order 'for free' to a selective system that can then modify and add further regularity.)

24 I am not much concerned with the fallacies of ultra-Darwinism within evolutionary biology, for most professionals understand the limitations of such a view only to well––and the current leading exponent, Richard Dawkins, seems to maintain a strict attachment to the creed that can only be called theological.

25 In fact, nothing could forth more annoyance from this remarkably genial man [Darwin] than the distortion of his theory into a cardboard version that equates natural selection with the exclusivity and omnipotence of Boyle's deity (and, on this ground, I am confident that Darwin would have eschewed ultra-Darwinism). For example, he wrote in near despair for the last edition of the Origin of Species (1872, p. 395):

As my conclusions have lately been much misrepresented, and it has been stated that I attribute the modification of species exclusively to natural selection, I may be permitted to remark that in the first edition of this work, [26] and subsequently, I placed in a most conspicuous position––namely at the close of the Introduction––the following words: 'I am convinced that natural selection has been the main, but not the exclusive means of modification.' This has been of no avail. Great is the power of steady misrepresentation.

31 The basic idea of positional information is that the cells acquire positional identities with respect to certain boundaries, rather like specifying position with a system of co-ordinates.

34 …homeotic… mutations in these genes ca cause the alteration of one structure into another, which is known as homeosis. … the order of the genes along the chromosome is co-linear with the order in which they are expressed along the antero-posterior axis. … all the genes contain a rather similar small region known as the 'homeobox', which codes for part of the protein that binds to DNA.

37 …in a sense, evolution has been quite conservative, even lazy, in its invention of developmental mechanisms.

38 Here, I try to present a scenario––a 'just so story'–– whereby the eukaryotic cell could have evolved multicellular embryonic development. A central requirement of this is that each stage must have a selective advantage and that there is continuity between stages.

40 …in all multicellular organisms that develop from an egg the somatic cells sacrifice themselves for the survival of the egg. … the Baldwin effect… extended by the British embryologist Conrad Waddington into what he called 'genetic assimilation'. In essence it involves an environmentally produced effect becoming part of the developmental programme. An environmental signal is replaced by a developmental one.

50 Horses had been playing a decisive role in military history ever since they were domesticated at around 4000 B.C. in the Ukraine.

52 …only a tiny fraction of wild mammal and bird species has been successfully domesticated, because domestication requires that a wild animal fulfil many prerequisites: a diet that humans can supply, a sufficiently rapid growth rate, a willingness to breed in captivity, tractable disposition, a social structure involving submissive behaviour towards dominant members of the same species (a behaviour transferable to dominant humans) and lack of a tendency to panic when fenced. Thousands of years ago, humans domesticated every possible large wild mammal species worth domesticating, with the result that there have been no significant additions in modern times, despite the efforts of modern science.

53 Eurasia's east/west axis means that species domesticated in one part of Eurasia could easily spread thousands of miles at the same latitude, encountering the same daylength and climate to which they were already adapted. … In contrast, the north/south axis of the Americas [and Africa] meant that species domesticated in one area could not spread far without encountering daylengths and [54] climates to which they were not adapted.

56 All of Africa's mammalian domesticates––cattle, sheep, goats, horses, even dogs……entered sub-Saharan Africa from the north, from Eurasia.

58 …a north/south axis and a paucity of wild plants and animal species suitable for domestication were doubly decisive in African history, just as they were in Native American history.

61 All things being equal, the rate of human invention is faster, and the rate of cultural loss is slower, in areas occupied by many competing societies with many individuals and in contact with societies elsewhere.

64 …I argue that London, like other complex urban systems, is a fragile and delicate structure that has come full circle in the cycle of evolutionary change. … Intelligent forward planning, anticipatory design and government intervention are necessary to avoid the process of gradual decline and eventual extinction that has affected urban cultures in the past.

70 …just as the elevator made the skyscraper possible…

77 The raw material of the new economy is, as ever, citizens and their knowledge––creativity and initiative. Art and science will be the life blood of knowledge-based development and th key to creation of [78] further wealth.

79 The verb 'to evolve', form the Latin evolvere, originally meant to roll out or unfold. Darwin, as is well known, used the word only once in the first edition of The Origin of Species. It is, in fact, the very last word of the book, and is used in its original sense to convey the idea of the history of life as a grand procession of forms unfolding before the the timeless gaze of the observing naturalist.

81 …Darwin was simply not concerned with the evolution of life as Spencer had conceived of it––that is, as one phase of a cosmic movement tat continually builds itself, through its own properties of dynamic self-organization, into ever novel and increasingly complex structures. His aim was much more modest: to account for the endless adjustment, remodelling and fine-tuning of those manifold and ingenious contrivances by which the current of life… had been carried into every nook and cranny of the habitable world. … the new generation of DWM [descent with modification] theorist would be anxious to correct anyone foolish enough to think that the adaptive modification of species amounted to a kind of evolution. For that… is to confuse phylogenetic change with ontogenetic development. Only the latter, underwritten as it is by a unique programme encoded in the organism's genetic endowment, has the character of the progressive unfolding of organized complexity to which the concept of evolution properly applies.

82 …I am still of the view that developmental biology, rather than DWM theory in its current neo-Darwinian guise, is the most promising place from which to start in the project of integrating biological and social science.

83 It is not my purpose, however, to contend that we need one kind of theory for human beings and another for the rest of the animal kingdom, nor do I mean to come out in favour of Canon Kingsley, to the effect that human beings, having become conscious of the laws of nature, are free to contravene them whenever they feel like it. To the contrary, I aim to show that a paradox of neo-Darwinian evolutionary biology is that it presumes, yet cannot comprehend, the historical process whereby certain humans came to be in a position to formulate it. Although Darwin could explain natural selection, natural selection cannot explain Darwin himself!

87 Those who would seek to construct an order of society, on whatever ideological foundation, must already dwell in a world of other persons and relationships, so that the institutional forms they create are themselves constituted within the flow of social life. …the reality of social life is no more contained within the things we call societies than is history contained within the fabrications of the human mind.

89 Evolutionary theory, it seems, requires hunter-gatherers. …the question of whether human beings differ from other animals in degree or in kind.

90 [ca. 1870] Human history––or what had now come to be called the evolution of society––was understood to march hand-in-hand with the evolution of the brain, through a process of natural selection in which the hapless savage, cast in the role of the vanquished in the struggle for survival, was sooner or later destined for extinction. When Wallace suggested, in his Contributions to the Theory of Natural Selection of 1870, that the brains of primitive savages might be just as good as those of European philosophers, and therefore designed to be capable of more than was actually required of them under their simple conditions of life, he was dismissed as a spiritualist crank. For natural selection, it was argued, will furnish the savage only with as much brain power as he needs to get by. Only a Creator would come to think of preparing the savage for civilization in advance of his achieving it.

91 It was really not until after the Second World War, and the atrocities of the Holocaust, that such [i.e., racist] notions ceased to be tolerated in scientific circles. But this left the Darwinian with a problem on their hands. How was the doctrine of evolutionary continuity to be reconciled with the new-found commitment to universal human rights? The Declaration of Human Rights of the United Nations asserted, once again, the fundamental equality of all humans––present and future and, by implication, past as well. … Face with this problem, there was only one way for modern science to go; that is, back to the eighteenth century. … History, as psychologists David Premack and Ann James Premack have recently pronounced, is 'the sequence of changes through which a species passes while remaining biologically stable', and of all the species in the world, only humans have it.

93 In effect, the category of 'hunter-gatherer' was brought in to characterize the original condition of humanity at the cross-roads of two processes of change––the one evolutionary, the other historical––whose separation is logically necessary in order to preserve the claim of science to deliver an authoritative account of the workings of nature in the face of the recognition that the scientist (who, like the rest of us, is only human) belongs to a species that has itself evolved to its present form through a process of variation under natural selection. Humans did not evolve as scientists, but they are thought to have evolved with the capacity to be scientists, and for that matter to read and write, to play the piano, drive cars and even fly rockets to the moon; indeed, to do anything that human beings have ever done or will do. … Stretched between the poles of nature and reason, epitomized respectively by the contrasting figures of the hunter-gatherer and the scientist, is supposed to lie the entirety of human history. … In sum, contemporary evolutionary biology remains locked in the same contradiction that has been there all along. Its claim, that human beings differ from their predecessors in degree rather than in kind, can be upheld only by attributing the total movement of history, from Pleistocene hunting and gathering to modern science and civilization, to a social or cultural process that differs in kind, not degree, from the process of evolution. This contradiction is, of course, but a specific instance of a more general paradox that lies at the heart of Western thought, which has no way of comprehending human beings' creative involvement in the world save by taking themselves out of it.

94 Gazing into the mirror of nature, the scientist sees his own powers of reason reflected back in the inverted form of natural selection. Despite the claims of evolutionary theorists to have dispensed with the archaic subject/object and mind/body dualisms of Western thought, they are still there, albeit displaced onto the opposition between the scientists, to whose sovereign imagination is revealed the design of nature, and the hunter-gatherer whose behaviour is interpreted as the output of innate dispositions installed by natural selection, and of which he or she has no conscious awareness. … Relations are enfolded in persons, in their particular capacities, dispositions and identities, and unfold in purposive social action.

95 …we can no longer accept the idea, central to neo-Darwinian orthodoxy, that human capacities are pre-specified, in advance of development, by virtue of some innate endowment that every individual receives at the point of conception. My contention, to the contrary, is that such capacities arise as emergent properties of the total developmental system constituted by way of the emplacement of the person-to-be, from the outset, within a wider field of relations––including, most importantly, relations with other persons. …My own view… is that sociality is immanent in that very field of relations within which every human life inaugurated and through which it seeks fulfilment.

96 …an agricultural analogy. Farmers do not create crops; they grow them. Through their work in the fields, they establish the environmental conditions for the plants' healthy development. Now just as farmers grow crops, so people 'grow' one another. And it is int eh growing of person, I suggest, rather than in the creation of society, that history is made.

97 That the constituent elements of design are thus imported into the organism, as a kind of evolved architecture, prior to the organism's development within an environmental context, is I believe one of the great delusions of modern biology. To be sure, every organism begins life with its complement of DNA in the genome, but on its own, DNA specifies nothing. There is no 'reading' of the genetic code that is not itself part of the organism's development in its environment. … What is literally passed on from one generation to the next, as Susan Oyama has pointed out in her important book The Ontogeny of Information: Developmental Systems and Evolution, 'is a genome and a segment of the world'. … For Darwin was no Darwinist, let alone a neo-Darwinist, and he was a great deal more sensitive than many of those who nowadays yoke his name to their cause. … It is curious, and not a little disturbing, that Darwin's heresy has now become [98] a new orthodoxy, bordering in some cases almost on faith. Those who claim that neo-Darwinism must be right because there is no alternative, and dismiss all doubters as heretics and enemies of Science, are surely the Wilberforces of the late twentieth century.

108 The absence/presence of the human in Darwinian theory as Darwin presents it has been a temptation to many interpreters within and beyond fiction. The apparitional quality of the human in his argument in the Origin produces a kind of flirtation that makes readers and commentators desperate to restore humankind to a stable centrality.

109 Evolutionary thinking is not a grid; it is a bundle of apprehensions.

119 Sudden loss of symmetry is seen in many of the most important phase transitions as the universe evolves.

121 Both in the non-living universe and on the living earth, evolution alternates between long periods of metastability and short periods of rapid change.

124 The effect of a concept-driven [scientific] revolution is to explain old things in new ways. The effect of a tool-driven revolution is to discover new things that have to be explained.

127 The Aristotelian view [of the celestial sphere as a place of perfect peace and harmony] still dominated the practice of astronomy until 1935. [Fritz] Zwicky was the first astronomer who imagined a violent universe.

131 …a terabyte being a million megabytes.

149 'Ever since the beginning, gravity's "anti-thermodynamic" effects have been amplify[151]ing inhomogeneities, and creating progressively steeper temperature gradients––a prerequisite for emergence of the complexity that lies around us ten billion years later, and of which we are a part.'

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