Evolution: more genomic evidence of pre-planning (Evolution)

by David Turell , Wednesday, February 24, 2021, 15:15 (1366 days ago) @ dhw

DAVID: Your old proposal is thinking of a new weapon, a spear, enlarged the brain.

dhw:Not just thinking of it, but designing it and learning how to use it.

DAVID: All we know from our brain is that it stays the same size and complexifies. Since new organs build on past capacities I think it is reasonable to complexification mechanisms were present in all older smaller brains. No need for expansion.

dhw: Of course it’s reasonable to suppose that their brains complexified. But it is equally reasonable to suppose that since their brains were smaller, there was less capacity for complexification! And so when that capacity had been reached, more cells were needed. You have yourself pointed out that even within our modern brains, certain parts expand when needed. And why on earth would your God have expanded the smaller brain if the extra capacity was not needed?

Remember, my God obviously expanded in anticipation of need, as sapiens brain history shows.

Behe

DAVID: Talk around it all you wish, but what you have said is in adaptation genes (information) are discarded. I've agreed new genes may be added.

I’m not talking round anything. I’m pointing out that adaptations and innovations will make certain genes unnecessary and so they will be discarded. That does not mean that the loss of genes CAUSES the adaptation/innovation

DAVID: Back to Behe:
https://salvomag.com/article/salvo49/darwinism-dissembled

Here’s a summation of the evolutionary picture that has emerged, according to Behe:
• The large majority of mutations are degradatory, meaning they’re mutations in which the gene is broken or blunted. Genetic information has been lost, not gained.
• Sometimes the degradation helps an organism survive.
• When the degradation confers a survival advantage, the mutation spreads throughout the population by natural selection.
In genetics, a loss of information generally translates into a loss of function, so it might seem counterintuitive to suppose that a degradatory mutation would confer a survival advantage. Behe gives several examples, though, of instances where damaged genes have been shown to aid survival. In the case of the sickle-cell gene, for example, a single amino acid change causes hemoglobin to behave in a way that inhibits growth of the malaria microbe. It’s a loss-of-function mutation, but it confers a survival advantage in malaria-prone regions.
Sickle cell is a prime example. Proper hemoglobin is damaged, degraded.

dhw: We were not discussing mutations! This is getting absurd. A mutation is not a loss, it is a change, and sickle cells have nothing whatsoever to do with the subject of adaptation and speciation. The sickle cell may have developed as a counter to malaria, but it is also the cause of sickness (anaemia)! (My wife had sickle cells, but fortunately only mildly). It’s good to hear you talk of the role survival plays in evolution, but you do yourself no favours by pretending that sickle cells and other examples of beneficial mutations somehow prove that the loss of genes causes adaptation and innovation.

Your wife had sickle trait, which means from one parent. I'll stick with Behe's interpretation that the sickle mutation was obviously degrading proper hemoglobin shape.