Living cells communicate (Introduction)

by dhw, Tuesday, October 16, 2012, 14:46 (4423 days ago) @ dhw

DAVID (under "Epigenetics: a negative review":)- http://online.wsj.com/article/SB10000872396390443294904578048381149899900.html?KEYWORDS...The truth appears to be slightly more positive than Ridley's opinion.-As Dr. Davey Smith puts it: 'The conclusion from over 100 years of research must be that epigenetic inheritance is not a major contributor' to physical resemblance across generations."-Thank you for summarizing this article. As always, I'm feeling my way into the science and need guidance. Ridley and Dr Smith seem to be arguing that epigenetic changes are not lasting. If we follow the hypothesis that the driving force behind innovation ... without which there would be no evolution ... is the intelligent cell, which either adapts to or exploits changes in the environment, the crucial point of epigenetics would be the exact opposite of this conclusion: namely, that new combinations must be heritable and lasting. However, there are so many different, interacting mechanisms at work within the cell itself, I wonder how precise scientists can be at present in identifying and separating genetic and epigenetic factors.-Innovation, unlike adaptation, means new functions, new organs, new forms of life. (I hesitate to use "species" since one form can be split into so many "species".) Overkalix and the other case studies were not concerned with new forms at all. Humans remained human and rats remained rats (of which there are 64 known species, according to Wikipedia). Innovation leading to totally new forms would arise from major and permanent changes in the environment, and such upheavals have become increasingly less common as the Earth has aged and stabilized. Perhaps the Bird of Paradise clip offers a clue here, in that there are certain creatures that are unique to one particular environment. Madagascar is another good example. In short, I don't see the relevance of Dr Davey Smith's findings to a process we cannot reproduce: namely, that of new forms of life emerging from new and/or unique environments through the ingenuity of perhaps just one set of cells in one original creature (a non-random mutation). Once the new combination is found to work, it establishes itself as per Darwin's theory.
 
I know, David, that you see humans as the culmination of the evolutionary process, and maybe they are. This would suggest that the intelligent cell has now exhausted its innovative repertoire ... whether that is God's plan or not. Alternatively, there may come a time when there are further dramatic environmental upheavals which produce further dramatic innovations. How can we ever know the full potential of the cell or of the mechanisms that govern its behaviour?