Evolution: a different view with loss of traits (Introduction)

by David Turell , Friday, November 16, 2018, 00:54 (1990 days ago) @ David Turell
edited by David Turell, Friday, November 16, 2018, 01:52

Found in a large study of yeast:

https://www.sciencedaily.com/releases/2018/11/181108142321.htm

"Collecting such a deep pool of yeast types gave researchers enough information to use comparisons of the shifting genetics to redraw the budding yeast family tree into a dozen major branches and paint a detailed picture of their past.

"'By having a very broad swath of biodiversity, it allows us to reconstruct the evolutionary processes through time," Hittinger says. "That's what allows us to make the inference that much of budding yeast evolution occurred through the process of reductive evolution, where you have a relatively metabolically complex common ancestor losing traits through time."

***

"The original Saccharomycotina was probably more complex than its descendants in an important regard.

"The researchers examined their yeasts for 45 traits representing their ability to process a variety of yeast foods -- different sources of carbon and nitrogen necessary to store energy and build cells. Tracking back the evolutionary paths of modern yeasts suggests the common ancestor yeast had a metabolism that could work with a varied diet.

"'We have a more consistent picture now of the variations of carbon and nitrogen sources across the modern species," says Dana Opulente, a postdoctoral researcher in Hittinger's lab who redid much of the trait-testing work of a century of yeast researchers for the Cell study. "They show us that this ancestor yeast would have been able to use a wider array of sugars than modern budding yeasts."

"Modern yeasts have narrowed their appetites in a process called reductive evolution, losing quite a few of those 45 traits as they specialized to flourish in their particular niches.

"To pick on the model budding yeast, S. cerevisiae has one of the more reduced genomes," Hittinger says. "It lacks many of the metabolic capabilities that other budding yeasts have."

Comment: This fits with the theory presented by Behe in his new book in that advancing evolution involves a devolution in DNA:

" Twenty years after publishing his seminal work, Darwin’s Black Box, Behe shows that new scientific discoveries point to a stunning fact: Darwin’s mechanism works by a process of devolution, not evolution. On the surface, evolution can help make something look and act different, but it doesn’t have the ability to build or create anything at the genetic level.

"Critically analyzing the latest research, Behe gives a sweeping tour of how modern theories of evolution fall short and how the devolving nature of Darwin’s mechanism limits them even further. If we are to get a satisfactory answer to how the most complex, stunning life-forms arose, it’s time to acknowledge the conclusion that only an intelligent mind could have designed life.

"We’re told that the basic thesis is, The First Rule of Adaptive Evolution: Break or blunt any functional gene whose loss would increase the number of offspring."

https://uncommondescent.com/evolution/a-peek-at-mike-behes-new-book-darwin-devolves/

Comment: I'll have to read it.