Friday, November 25, 2011

Deconstructing natural selection

One of the great myths of our day is the idea of a creative natural selection. In this post I'll make a couple comments on a review of the book 'Genetic Entropy & The Mystery of the Genome' by John C. Sanford

Quotes and comments;

1. 'Any trait such as intelligence, speed or strength depends on gene characteristics and environmental factors (nutrition, training, etc.) For example, height is about 30% (h2 = 0.3) heritable. For complex traits such as ‘fitness’ heritability values are low (i.e. 0.004). ‘This is because total fitness combines all the different types of noise from all the different aspects of the individual.’ Low heritability means bad genotypes are very difficult to eliminate. Survival becomes primarily a matter of luck, and not better genes: [1.]

- When darwin famously said that 'nature' could do more than animal breeders he wasn't being honest, but what he failed to mention was crucial; if you take animals that have been bred for a purpose and then turn them loose, those specially bred charactersistics will soon disappear and the animal will revert to norm.
The godlike creative powers of natural selection is an utter myth.

2. 'Furthermore, almost all mutations are recessive, camouflaging their presence and hindering selection against them (pp. 56, 76). Another consideration, not explicitly brought out in this book, is that key environmental factors (disease, temperature, mutation, predators, etc.) affecting survival vary over time. Strong selection must be present for a huge number of generations if fixation of a (temporarily) favourable trait throughout a population is to occur. Relaxation for just a few generations could undo this process, since selection for a different trait would then be at the expense of the preceding one.

- The textbook model of how n.s. works is a rationalistic construct bearing little resemblance (in most cases) to reality.

3. 'We must recognize clearly this lack of strong correlation between a mutation (whether having a positive or negative effect) and reproductive success. It is a fact of nature, yet most people attribute incorrectly near miraculous creative powers to natural selection.

- The collapse of the natural selection myth leaves Darwinism in tatters... a flag reduced to a few threads.

4. '...the degradation of the human genome (in the presence of such high mutations rates, preponderance of deleterious mutations and lack of huge expendable proportions of offspring) cannot be avoided...'

- I see no way progressive evolution is possible under these circumstance.

5. 'In the 1950s, one of the most famous population geneticists, John Burdon Sanderson Haldane, presented an observation known as ‘Haldane’s dilemma’ (p. 128): it would take (on average) 300 generations to select a single new mutation to fixation. However, his calculations were only for independent, unlinked mutations. He assumed constant and very strong selection for a single trait, which is not realistic. The interference by hundreds of random mutations was not taken into account. Even so, selection for only 1,000 specific and adjacent mutations could not happen in all putative evolutionary time. There is no way an ape-like creature could have been transformed into a human (p. 129). Man and chimp differ at roughly 150 million nucleotide positions (p. 130) and humans show remarkably little variation worldwide.

- The actual case is far more extreme than Haldane could possibly have known. The famous Darwinian icon of a line of apes being slowly transformed into a human being is a completely fallacious invention. It's a travesty of education that this bit of propaganda is featured in textbooks for children.

- M. Johnson

Notes;
1. A review of Genetic Entropy & The Mystery of the Genome by John C. Sanford, Ivan Press, Lima, New York, 2005 - by Royal Truman