A new theory (Introduction)

by dhw, Tuesday, May 21, 2013, 16:54 (4012 days ago) @ David Turell

Many thanks to David, who has alerted us to a "new theory".-http://ep.physoc.org/content/early/2013/04/12/expphysiol.2012.071134.full.pdf+html-David has quoted the conclusion, but it's the abstract that sets the bells ringing for me:-The "Modern Synthesis" (Neo-Darwinism) is a mid-twentieth century gene-centric view of evolution,based on random mutations accumulating to produce gradual change through natural selection. Any role of physiological function in influencing genetic inheritance was excluded. The organism became a mere carrier of the real objects of selection: its genes. We now know that genetic change is far from random and often not gradual. Molecular genetics and genome sequencing have deconstructed this unnecessarily restrictive view of evolution in a way that reintroduces physiological function and interactions with the environment as factors influencing the speed and nature of inherited change. Acquired characteristics can be inherited, and in a few but growing number of cases that inheritance has now been shown to be robust for many generations. The twenty-first century can look forward to a new synthesis that will reintegrate physiology with evolutionary biology.-In our many discussions over the years, David and I have agreed that random mutation and gradualism are major problems in Darwin's theory. In my own amateur meanderings, I have been plugging interaction with the environment as a twofold trigger for innovation by an intelligent mechanism within the genome: 1) necessity, which I think is more likely to lead to adaptation than to innovation, and 2) opportunity, as changes in the environment may lead to experimentation. But if acquired characteristics can be inherited, this has to be another way of saying that changes in the body can cause changes in the genome.- There is an eye-opening sentence in the conclusion, quoting Mattick:
"The available evidence not only suggests an intimate interplay between genetic and epigenetic inheritance, but also that this interplay may involve communication between the soma and the germline."-The author stresses the work of McClintock, who claimed that "the genome is an organ of the cell" and who, if you remember, called for research into the degree to which the cell might have knowledge of itself. He also refers to Margulis' work on symbiogenesis, though not to her more general ideas about cooperation.-It seems to me that if you put all these factors together ... rejection of randomness, interaction between organisms and environment, inheritance of acquired characteristics, communication and cooperation between all the cells and sets of cells ... the picture entails just the sort of mechanism we have been discussing. However, David, I need your guidance on one piece of this jigsaw puzzle. If innovation can come about through interplay between the genetic and the epigenetic, and between the soma and the germ line (i.e. intelligent cooperation between all parts of the body), would not this "new theory" suggest that the "intelligent cell" might after all be more accurate terminology than the "intelligent genome"?


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