Google
Custom Search

Thursday, November 19, 2009

Is nature really a struggle in which natural selection is the key factor?

British physicist David Tyler comments:
In a perceptive essay, Daniel Todes focuses attention on the reactions of Russian biologists to Darwin's writings. Many of these naturalists "were evolutionists before 1859", so they did not dissent from common ancestry. However, their experiences of the living world were quite different from Darwin and Wallace, who drew their inspiration from densely populated tropical forests and related habitats. They witnessed a struggle for existence that matched the description Thomas Malthus had given of human communities. Using the same logic, Darwin and Wallace were stimulated to think about winners and losers in populations of animals and plants. The Russian scientists lived in a different world.

[They] "investigated a vast under-populated continental plain. For them, nature was not an "entangled bank" - the image Darwin took from the Brazilian jungle. It was a largely empty Siberian expanse in which overpopulation was rare and only the struggle of organisms against a harsh environment was dramatic."

The Russian response to living in a harsh environment was to develop "the language of communalism - stressing not individual initiative and struggle, but the importance of cooperation within social groups and the virtues of social harmony." The analysis of Malthus did not match the biological communities in their part of the world, so Darwin's metaphor of the "struggle for existence" was not, in their view, well grounded.
That's always what bothered me. I see competition in nature, to be sure, but also lots of cooperation. Otherwise, life could not survive against non-life. There is much more non-life than life. That much should be obvious. For more, go here.

Tyler also points out that the modern synthesis that is supposed to save Darwinism is gone.
Earlier this year, Eugene Koonin published a masterly analysis of the impact of genomics on evolutionary thinking. This proved to be too meaty a study for a concise blog, and my initial draft was abandoned. Happily, a shorter overview has now been published, and this abstracts salient points from the research paper. Koonin notes that the 1959 Origin centennial was "marked by the consolidation of the modern synthesis" but subsequent years have witnessed great changes which have undermined its credibility. "The edifice of the modern synthesis has crumbled, apparently, beyond repair."

Koonin uses the metaphor of "the landscape of evolutionary biology". There are three distinct revolutions have occurred over the past half-century: the molecular, the microbiological and the genomic revolutions.

"[T]his year is the perfect time to ask some crucial questions: how has evolutionary biology changed in the 50 years since the hardening of the modern synthesis? Is it still a viable conceptual framework for evolutionary thinking and research?"

The molecular revolution culminated, says Koonin, in the neutral theory, which means that purifying selection is more common than positive selection. The microbiological revolution brought the world of prokaryotes into the domain of evolutionary biology, but it then became apparent that the concepts of Darwinism and the modern synthesis "applied only to multicellular organisms". The genomic revolution revealed that the living world was "a far cry from the orderly, rather simple picture envisioned by Darwin and the creators of the modern synthesis". In particular, it is now interpreted as an "extremely dynamic world where horizontal gene transfer (HGT) is not a rarity but the regular way of existence, and mobile genetic elements that are vehicles of HGT are ubiquitous". "The discovery of pervasive HGT and the overall dynamics of the genetic universe destroys not only the tree of life as we knew it but also another central tenet of the modern synthesis inherited from Darwin, namely gradualism. In a world dominated by HGT, gene duplication, gene loss and such momentous events as endosymbiosis, the idea of evolution being driven primarily by infinitesimal heritable changes in the Darwinian tradition has become untenable."

Koonin is serious in saying that all the concepts of the modern synthesis are in need of a fundamental overhaul. "Moreover, with pan-adaptationism gone forever, so is the notion of evolutionary progress that is undoubtedly central to traditional evolutionary thinking, even if this is not always made explicit. The summary of the state of affairs on the 150th anniversary of the Origin is somewhat shocking. In the postgenomic era, all major tenets of the modern synthesis have been, if not outright overturned, replaced by a new and incomparably more complex vision of the key aspects of evolution. So, not to mince words, the modern synthesis is gone."

Koonin tentatively identifies two candidates to fill the vacuum left by the discarded modern synthesis. The first of these appears to emphasis the role of chance; the second appears to emphasise law. "The first is the population-genetic theory of the evolution of genomic architecture, according to which evolving complexity is a side product of non-adaptive evolutionary processes occurring in small populations where the constraints of purifying selection are weak. The second area with a potential for major unification could be the study of universal patterns of evolution such as the distribution of evolutionary rates of orthologous genes, which is nearly the same in organisms from bacteria to mammals or the equally universal anticorrelation between the rate of evolution and the expression level of a gene. The existence of these universals suggests that simple theory of the kind used in statistical physics might explain some crucial aspects of evolution."

It is not difficult to predict that Koonin's analysis will not be received quietly by the very vocal leaders of evolutionary biology. They are still entrenched in neoDarwinism and show no signs of conceding any ground to anyone.
Go here for more.

Actually, Koonin is just as likely to be ignored as not quietly received. The fantasy creation story of fashionable atheism is in many places, government policy. Its proponents often have tenure and get their pay every month. The only solution is eventual retirement parties, followed by a big revaluation - = what do we really know?

Find out the real reason why there is an intelligent design controversy:

Labels:

Links to this post:

Create a Link

<< Home

Who links to me?