A Paradigm Shift In Evolutionnary Theory ?

The modern interpretation of evolutionnary theory, known as Neodarwinsim, has put too much emphasis on some aspects of the theory: Competition, Adaptation, and Genes. Those themes became popular among evolutionnary scientists and eclipsed many others. The great evolutionnary biologist Ernst Mayr stated that there are four major components to the theory:

Common origin
Evolution by Random variations
Selection
Adaptation

The last two processes are thought to result in the survival of the fittiest.

Only the common origin stands outside scientific scrutiny today. And while random variations are not disputed, their role in evolution has been questioned by, among others, Lynn Margulis who advocated symbiogenesis, instead of random genetic variations, as the main factor in evolution. Selection and Adaptation, which are interdependant in Neodarwinism, leading to the survival of the fittiest, were seen by the late evolutionnary biologist Stephen Jay Gould as anthropomorphic concepts borrowed by Darwin from the social sciences of his time. Gould used to stress at the beginning of many of his talks that selection by adaptation and survival of the fittiest didn't work well for Adam Smith but worked for Darwin. As a matter of fact, Darwin, in a first draft of the theory, didn't mention fitness and adaptation. For a very long time, Darwin was reluctant to publish his book 'The origin of species by means of natural selection', he needed to fill some gaps in the explanation, and these gaps came from the social sciences at a time when Darwin was pressed by his friends to go ahead and publish his theory unless Wallace, who had the same intuition about evolution, was going to publish before him.
Gould found that the modern interpretation of two apsects of the theory of evolution, selection and adaptation, by emphasising the role of random variation of the gene to suit the environment, and later to suit the gene itself, according to Dawkins' 'selfish gene', has a teleological feature. This is a negative statement since science and nature have no goals, no intention. Only humans, and God, have purpose. For Gould, there is no goal in Nature, not even adaptation, there are only chance, accident, and contingency.

At the heart of this modern interpretation of Darwin's theory there is an old definition to a concept not well understood, the concept of Species. For a very long time, the concept of Species was understood from the standpoint of interbreeding: animals fronm the same Species are those who can interbreed. There were some recognised minor exceptions, but they were still exceptions. However, a new study is going to shake this definition and with it probably the edifice of the modern interpretation. This new study is not the only one to question the old definition of Species. Lynn Margulis, who studied bacteria, showed that small organisms, like bacteria, swap their genes very frequently. This process is the last step in symbiotic life, when symbiosis between two Species is long enough to change the phenotype of both organisms when they are not in symbiosis,and when it leads to some mix of genes in the new organism. Indeed, says Margulis, because of frequent gene swap in bacteria, one can affirm that there are no Species in bacteria. Margulis was one of the few evolutionnary biologists working at the margins of the Neodarwinist paradigm, claiming that Neodarwinism neglected data from small organisms and from symbiotic life, in the interpretation, and concerned itself only with big animals and competition. For her, small organisms, and symbiogenesis tell us a different story on Evolution. A story of cooperation instead of competition.

Indeed, the new study suggests that:

As more and more genes were sequenced, it became clear that the patterns of relatedness could only be explained if bacteria and archaea were routinely swapping genetic material with other species - often across huge taxonomic distances - in a process called horizontal gene transfer (HGT)...As it became clear that HGT was a major factor, biologists started to realise the implications for the tree concept. As early as 1993, some were proposing that for bacteria and archaea the tree of life was more like a web. In 1999, Doolittle made the provocative claim that "the history of life cannot properly be represented as a tree" (Science, vol 284, p 2124). "The tree of life is not something that exists in nature, it's a way that humans classify nature," he says

Horizontal Gene Transfer (HGT) is opposed to the classical vision of Gene Transfer, which is the vertical one in the Tree of life of Darwin, the vertical descent of Species.
Interbreeding is swapping genes. And swapping genes between unicellular animals, even unicellular eukaryotes, when it happens in multicellular and big animals is called hybridisation. Most scientists concerned with big animals think that hybridisation is an exception. But that's not the fact. The fact is that hybridisation concerns more than 10% of multicellular eukaryotes (i.e. organisms). And genetic studies of big animals are revealing that HGT is happening in big animals also as ''ever more incongruous bits of DNA are turning up in multicellular genomes''.

Last year, for example, a team at the University of Texas at Arlington found a peculiar chunk of DNA in the genomes of eight animals - the mouse, rat, bushbaby, little brown bat, tenrec, opossum, anole lizard and African clawed frog - but not in 25 others, including humans, elephants, chickens and fish. This patchy distribution suggests that the sequence must have entered each genome independently by horizontal transfer (Proceedings of the National Academy of Sciences, vol 105, p 17023).

And what exactly does this mean for the tree of life of Darwin and for the Theory of Evolution ?

...downgrading the tree of life doesn't mean that the theory of evolution is wrong - just that evolution is not as tidy as we would like to believe. Some evolutionary relationships are tree-like; many others are not.

That's one reassuring point of view.

And the one that is not reassuring:

"Our standard model of evolution is under enormous pressure. We're clearly going to see evolution as much more about mergers and collaboration than change within isolated lineages."
Rose goes even further. "The tree of life is being politely buried, we all know that," he says. "What's less accepted is that our whole fundamental view of biology needs to change." Biology is vastly more complex than we thought, he says, and facing up to this complexity will be as scary as the conceptual upheavals physicists had to take on board in the early 20th century.

If we reconsider Mayr's components for Darwin's theory (listed above), we may end up with a completely different picture:

Common origin
Evolution, not so much by random variations, but by Horizontal Gene Transfer (HGT), or interspecies breeding, or symbiogenesis
Selection and adaptation by survival of the fittiest are replaced by cooperation.

Exit Richard Dawkins, Daniel Dennett, Steven Pinker, Jean-Pierre Changeux, and all those ultradarwinists that stressed vertical descent and competition. Enter Stephen Jay Gould, Lynn Margulis, and a new era of cooperative and messy Biology, a solidary world. The change of paradigm is certain. However, one might ask at the beginning of this economic and ecological crises if the new paradigm is not, yet again, influenced by what is going on in our human world...

New Scientist, 21 January, 2009. 'Why Darwin was wrong about the tree of life'

UPDATE 1: February, 10th, 09: Darwinism must die so that Evolution may live.
UPDATE 2: February, 10th, 09: The old paradigm is resisting.

Loneliness In Old Age Linked To Alzheimer's : When Mind and Society contribute to neurological disorders

This is a nice medical research study and it comes from practitioners in the field of Alzheimer's, not from fundamental research on animal models. However, researchers might be encouraged now to produce a credible laboratory model for loneliness to further investigate the question. We definitely need both fundamental and medical practice induced research.

Some diseases have biological and social manifestations, Parkinson, Tourette, Alzheimer's, Schizophrenia, and so on. They have also biological and social causes. However, the pervasiveness of materialist thinking among some scientists who work on the mind and in some intellectual circles makes it impossible to have a concept of a neurological disorder in sociological terms . I have an example: Ian McEwan's Saturday have two characters with neurological degenerative diseases; Baxter who has his early symptoms of Huntington disease and Perowne's mother who has Alzheimer. The central character is a neurologist and the author gives his neurologist a background theory on human consciousness, emotions, and behaviour which falls into the most reductivist materialist theories of mind. We are told details about the inner workings of the brain and what genes have to do with these diseases but we are not given a single hint about how modern scientific efforts in the field of Neurology and Psychiatry are tracking both the biological and psychosociological aspects, factors, and sometimes causes of the diseases. We are being served a vision of human mental life and behaviour that does not account for the dominant current paradigm in Neurobiological Sciences which considers human behaviour and consciousness as a result of a long history of transactions between Nature, personal history and Society.

The study on Loneliness and Alzheimer does not give a proof that loneliness is actually a cause but it does demonstrate that it is not a symptom of Alzheimer's. That is. It does not appear to be a behavioural result of the biological factors contributing to Alzheimer. On the contrary, it appears to be a contributing factor. And it surely exerts this influence through biological channels for emotions, stress and mood. It is not physical loneliness that matters here but the patient's own perceived loneliness. What matters to my brain is how I feel and what I think, this thing about me that cannot be reduced to few chemicals and some degenerate cells. Our biological Self is not shielded form our body, from our presence to the world - and not in the world, as Merleau-Ponty would put it. Biology does not exert a one way influence and initiate behaviour and thought with the internal biological machinery from the inside to the outside because this same machinery is actually structured by the outside, starting with the interface formed by our bodily and perceptual interactions in nature and society, and reaching deep into our biology, including gene expression (not gene sequence). From birth until death these interactions shape the biology of growth, maturity and old age, as in Loneliness and Alzheimer.

This study is a breakthrough and it will surely be followed by more scientific evidence gathered from other levels of organisation of this complexe entity that is the Human being. It is promising also for theories of consciousness because this kind of investigation occuring at a high level of mind functioning is needed to fill the explanatory gap between internal material causation in the explanation of consciousness, that is, causation that exists between the different parts and levels of the brain producing thoughts, emotions and behaviour, and the external material causation chain, causation linking outside factors, like ways of life and our social psychology, with the internal causative chain in the brain.

I smile when I remember that, in Mc Ewan's Saturday, Perowne takes great care not to eat cheese because he believes that fat helps build the degenerative plaques around brain cells leading to Alzheimer. What this study tells us however is that no matter how much we eat or don't eat cheese, the way we lead our life, give it meaning and directions, both psychologically and morally, is as important as the piece of cheese in the shaping of our old age physical diseases. And Perowne might as well develop Alzheimer, after all. Because in addition to the fact that he might have inherited a risk gene from his mother, his loneliness is obvious. The conscious stream of one day in his life tells the story of a lonely son, a lonely husband, and a lonely father. Although he is able to reach some empathy with the people who surround him, his empathy never reaches a level where he can consider himself through other people's eyes. He is so infatuated with himself and his knowledge that the reader is never presented with the slightest glimpse into what others think of Perowne. His loneliness is so evident when we consider his wife's character. This character is so flat and seen only through the eyes of Perowne as an object of love, pride and happiness that we never get to know who is the real person behind.

Maybe loneliness is, after all, the condition of the modern inner life of men and women in an era where individualism and personal achievement are perceived the number one criteria for happiness. Not the Other, not the Other... "Overall, these data suggest that both the quantity of social interaction and the quality of social attachments affect risk of late-life dementia," concluded the authors of the research.

In the Press: Loneliness linked to Development of Alzheimer's

Source article: "Loneliness and Risk of Alzheimer Disease."Robert S. Wilson, Kristin R. Krueger, Steven E. Arnold, Julie A. Schneider, Jeremiah F. Kelly, Lisa L. Barnes, Yuxiao Tang, David A. Bennett.Arch Gen Psychiatry. 2 February 2007;64:234-240.