Evolution: a different view with loss of traits; not Behe (Introduction)

by David Turell , Sunday, September 06, 2020, 15:11 (1325 days ago) @ dhw

DAVID: Your bolded proposal ignores the point of the article. It is now accepted that new mutations (new genes) are most always deleterious or if effective lead to minor alterations of no major consequence to furthering evolution. If read carefully, the article is in full support of Behe.

dhw: We are not talking about deleterious mutations but about gene loss. I challenged your statement that “advances ALWAYS result from loss of genes”. Look at the title: “By Losing Genes, Life Often Evolved More Complexity”. Often, not always.

The crutch of your leaning upon the word 'often' is refuted if you read the entire article with all of the studied cited. All implying loss of genes results in advances in form. I view 'often' as a hedge by the author about how current direction research is taking away from Darwin theory. A step most writers take hesitantly in today's resistance to leaving Darwin.

DAVID: Quoting the title and subtitle:
By Losing Genes, Life Often Evolved More Complexity
Recent major surveys show that reductions in genomic complexity — including the loss of key genes — have successfully shaped the evolution of life throughout history.
https://www.quantamagazine.org/by-losing-genes-life-often-evolved-more-complexity-20200...

Here are some quotes from the article:

But in reality, the majority of gene losses during evolution are likely to be neutral, with no fitness consequences for the organism…

The reason is that evolutionary gene losses often occur after some change in the environment or behaviors makes a gene less necessary. If a key nutrient or vitamin suddenly becomes more available, for example, the biosynthetic pathways for making it may become dispensable, and mutations or other genetic accidents may make those pathways disappear. Losses can also occur after a chance gene duplication, when the superfluous copy degenerates, since selection no longer preserves it.

Of course, the risk of evolving by jettisoning genes is that even if a gene is dispensable in particular environmental conditions, it might be needed again millions of years later, Jedd says. What then? It turns out that yeasts, at least, can sometimes get genes back.

Please note the emphasis on the influence of the environment, the necessity or otherwise of the gene (he uses the term "dispensable"), and the role played by selection. There is nothing in the article about innovation. It deals with adaptation. Under the photo of the author, we read: "Cristian Cañestro, a professor of genetics, microbiology and statistics at the University of Barcelona, has argued for years that gene loss can be an adaptive evolutionary force."

dhw: There is absolutely nothing in this article that contradicts my proposal bolded above.

The use of the word 'complexity' implies more than some adaptive modification. This article is couched in Darwin-protective terminology, but it supports, if carefully, the Behe direct attack. And please keep in mind, I have no 'hatred' of Darwin. He did the best he could. It is his current brain-dead researchers I abhor.