Evolution: a different view with loss of DNA segments (Introduction)

by dhw, Saturday, January 05, 2019, 12:52 (1932 days ago) @ David Turell

DAVID: Evolution can speed up by loss of fragile DNA segments a study in Stickleback fish shows:
https://phys.org/news/2019-01-strength-weakness-fragile-dna-regions.html

QUOTE: "When the last Ice Age ended, about 10,000 years ago, pockets of migratory ocean threespine sticklebacks colonized newly formed lakes and streams in coastal regions, and then evolved independently in response to their new local environments. As a result, many of these populations show significant differences in body structure. Marine sticklebacks, for example, have a hind fin with a large spine projecting down from their pelvic structure. In contrast, dozens of freshwater populations have lost that hind fin; its absence likely reduces their need for calcium and chances of being nabbed and eaten by hungry insects.” (dhw’s bold)

Previous studies in bacteria, mice and humans have indicated that these repeats are often associated with deletions of stretches of DNA. (David’s bold)

"Many vertebrates, including early humans, are dealing with a small population size and relatively long generation times…" (David’s bold)

DAVID’s comment: This research supports Behe's theory about loss if DNA driving evolution. Note the comment about small population size. There were never very many hominins, yet major changes occurred. Deletion appears to be a major concept, supporting the idea that original DNA had all the information needed for evolution. Note the DNA of an amoeba is larger than a human DNA but with just a few functional genes. Note my bold about bacteria.

Evolution is an ongoing process! You seem to have forgotten that the migratory ocean sticklebacks had already evolved their spines, but when they entered new environments, they needed different structures, which in some cases meant jettisoning structures which had evolved earlier. (Like pre-baleen whales' teeth.) I propose that the original DNA contained the ability to make these changes (the ability is the “information”, not the changes themselves, which = your 3.8 byo computer programme for every change). And yes indeed, small individual groups in different environments would explain why different structures evolved in order to cope with different environments. This is why I have proposed that a particular group of apes in a particular location may have decided (and most likely needed) to descend from the trees, whereas elsewhere their brothers had no problem.