Genome complexity; epigenetics: Lamarck is back (Introduction)

by David Turell , Wednesday, June 01, 2016, 01:34 (3099 days ago) @ dhw

This essay makes some interesting remarks about Lamarck and epigenetics, and the problems Darwin adherents and atheists are having:-http://www.abc.net.au/radionational/programs/ockhamsrazor/descartes-to-dawkins-history-of-machine-living-things/7438002-"One important person to describe living things self-transforming machines was 18th century French naturalist, Jean-Baptiste Lamarck.-"You might have heard of Lamarck as a crackpot: the man who said that giraffes' long necks are due to reaching high-up fruit. You may also have heard that Darwin got rid of Lamarck's idea of the inheritance of acquired characteristics. But in fact that's not true at all. Darwin was very much influenced by Lamarck.-"In particular, Charles Darwin believed in the inheritance of acquired characteristics, or what he generally called the effects of use and disuse—for example, that moles eventually evolved to be blind on account of not using their eyes.-"In that sense, Darwin was very much a Lamarckian. So why did we all learn in high school biology class that Lamarck was crazy and Darwin got rid of all his crazy ideas?-"Lamarck's description of evolution as resulting from living organisms' own agency threatened God's monopoly on creation. In the wake of the French Revolution, this made Lamarck seemed like a very dangerous sort of Frenchman.-"Around the turn of the 20th century, Darwinists wanting to promote a strong and viable Darwinism started trying to eradicate every trace of Lamarckism.-***-"Weismann cut the tails off mice in order to show that their offspring had perfectly normal tails. He presented his findings as a definitive refutation of Lamarck. His mice continue to appear in biology textbooks as just that. -"But of course, they had no bearing on Lamarck's theory at all—since Lamarck believed, as I've said, that organisms transformed themselves by acts of will, by habits and behaviours.-"You could hardly call having your tail lopped off an act of will, a habit or a behaviour. -***-"Today's neo-Darwinists—people such as Richard Dawkins and Daniel Dennett—are really Weismannians (in fact, Dawkins has called himself an ‘extreme Weismannian').-"Even outside of evolutionary biology, some of the most influential thinkers and writers in biology and cognitive science today have adopted the Weismannian view that living organisms are essentially passive, made of dumb and inert mechanical parts.-"Cognitive scientist Steven Pinker is an example: he has written that the human mind can be reduced to ‘armies of idiots'—mindless sub-routines in the brain that merely do what they are programmed to.-"The idea that mind can be reduced to mindlessness and living agency to passive mechanical parts is a central tenet of the New Atheism movement.-***-"The engineering or design model of living nature, which they have all adopted, implies a designer. If you truly want to eliminate the designer, you need to naturalise his agency: allow the possibility that living nature has the agency to create and transform itself. (my bold)-***-"What's especially fascinating to me is that Lamarckism has been making a comeback in the last 10 or 15 years: biologists have been finding various ways in which changes in an individual organism can be inherited.-"The field of epigenetics is largely devoted to this. Epigenetics studies all the ways in which factors outside the DNA shape the way an organism is formed, and many of these epigenetic factors can change in heritable ways.-"In this sense, an organism might have agency with regard to its evolutionary destiny, just as Lamarck thought."-Comment: Note my bold. This is the crux of my discussion with dhw. We still don't know exactly how the epigenetic adaptations we see can lead to new species, if at all.