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New genetic research shows that the flightless birds of the Southern Hemisphere descended from ancestors that flew. Each apparently from a separate species, not the single ancestor that previously was theorized. This appears to be an example of convergence as described by Simon Conway Morris in several different environments in parallel. It also raises the question of what is the advantage by natural selection of birds losing the ability to fly? Look at this website: http://www.eurekalert.org/pub_releases/2008-09/uof-nrc090308.php

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The article cited by David Turell is a good example of the way science works. New facts are discovered and old theories have to be revised. - There's an awful lot of interesting research now going on, particularly of course in genetics. You only need to look on Richard Dawkins . net to see something new every week. I could give links here, but it is easier to go to the site and click on the Science menu near the top of the page. - It's surely pretty obvious why some birds lose the power of flight. They arrive in a place where there is an abundance of food and a lack of predators so they don't need to waste energy on flight, and they grow larger until they are too heavy to fly any more.

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The article cited by David Turell is a good example of the way science works. New facts are discovered and old theories have to be revised. 
> It's surely pretty obvious why some birds lose the power of flight. They arrive in a place where there is an abundance of food and a lack of predators so they don't need to waste energy on flight, and they grow larger until they are too heavy to fly any more. - George's explanation as to why birds lose flight is a good guess, but we don't really know 'why'. His explanation fits Australia and New Zealand, but doesn't explain the Serengeti in Kenya and Tanzania. There the ostrich, which can run fast, live side by side with the red of tooth and claw: lions, leopards, and cheetahs. Ostriches can really move out, but cheetahs are the fastest animal on Earth. - And this is my real point. The genetic study of DNA/RNA will really help the suppositions of the Darwin Theory. Many of the after-the-fact explanations of evolution offered by Darwin scientists will be revised, but never having seen evolution in historical perspective, much of our knowledge will still be guess work, not as to the 'how' but as to the 'why'.

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The genetic study of DNA/RNA will really help the suppositions of the Darwin Theory. Many of the after-the-fact explanations of evolution offered by Darwin scientists will be revised, but never having seen evolution in historical perspective, much of our knowledge will still be guess work, not as to the 'how' but as to the 'why'.-Another example of Darwin going backwards. Or is it really backwards or another example of how evolution can vary? As George has pointed out with varying circumstances, such a development may be very reasonable. This one is dsappearing enamel, a very specialized tissue only in mammals.-http://www.sciencedaily.com/releases/2009/09/090904071650.htm-And here is another major study on 'relaxed selection', showing that certain traits can be lost rather quickly compared to standard evolutionary progression by mutation. Perhaps some epigenetics at work?-http://www.physorg.com/news171619970.html

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I don't think there is a "forward" or "backward" in evolution, only a "more adapted" or "less adapted." Snakes and whales or also examples of the loss of evolved features. The trend is toward more complex genomes, however. According to Wikipedia, the largest genome is that of the Amoeba. Evolution does not have an "objective", but is the outcome of a mindless process.

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According to Wikipedia, the largest genome is that of the Amoeba. Evolution does not have an "objective", but is the outcome of a mindless process. - I can confirm that Carl and Wikipedia are absolutely correct. (Never fully trust the information in Wikipedia.) The DNA of amoeba is larger than human DNA, which is over six-feet long stretched end to end, but the amoeba's DNA is mainly non-functional. Carl's declaration that evolution is a 'mindless process' is an unproven position, taken by Carl on faith. I can raise the question of why is an early entry on the tree of life so rich in potentially useful DNA? Pre-planning for the complexity to come? My statement/question comes with faith that pre-planning did or does exist. For example the pax-6 gene which controls eye development probably appeared over 600 million years ago (Conway Morris, The Crucible of Creation, 1998) whereas organisms that began to develop eyes appeared in the Cambrian Explosion, some 60-80 million years later. Conservation of a gene not being used for so many years smells of pre-planning. There are many other examples of conservation of this type.

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David says "Carl's declaration that evolution is a 'mindless process' is an unproven position, taken by Carl on faith."
Granted. It is just an opinion anyway, not a belief. I find the idea of intelligence being involved in natural selection implausible, unless it might be something like the ice age cycle. Mutation, on the other hand, is somewhat more plausible, since there is obviously a decision making process of sorts required in the cells reproduction machinery. It is conceivable that the machinery could be programmed to toss in a mutation every once in a while. Such a feature could tend to produce convergence, I presume.
But my opinion, based on what I know of evolution at this point, is still that it is a mindless process.

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From an article in The Guardian a few days ago: - "Early humans may have had help in mastering tools and walking upright from a chunk of DNA that scientists previously wrote off as junk, according to a study [by researchers at Yale and the Medical Research Council's human genetics unit]. The section of DNA - HACNS1 - is thought to have triggered off the development of hands and feet." - They "analysed DNA from macaques, chimpanzees and humans and identified sequences that appeared similar in all three, suggesting they had survived through history and so likely played a role in growth and development."

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From an article in The Guardian a few days ago:
> 
> "Early humans may have had help in mastering tools and walking upright from a chunk of DNA that scientists previously wrote off as junk, according to a study [by researchers at Yale and the Medical Research Council's human genetics unit]. The section of DNA - HACNS1 - is thought to have triggered off the development of hands and feet."
> 
> They "analysed DNA from macaques, chimpanzees and humans and identified sequences that appeared similar in all three, suggesting they had survived through history and so likely played a role in growth and development." - This piece from the Guardian is to my way of thinking another example of front-end loading. Mt thesis is a combination of taking Darwin's Theory, evolution as a fact, and evidence for intelligent design and arriving at a different way of looking at the issue. What must be accepted is evolution occurred, the universe is 13.7 billion years old, the Earth is 4.5 billion years old and life started (really jump-started) about 3.7 billion years ago. Junk DNA is not junk DNA. It is filled with regulatory RNA that permits making humans out of 25,000 genes, while simple organisms like a sea anemone may have 8-10,000 genes (I've forgotten the exact number). Many of the important gene combinations in our DNA are ancient! I suspect science will find that much RNA is ancient also, but not yet activated to create more complexity seen in the emergence of more recent animals and plants. The RNA activation lead to the Cambrian Explosion. Was the activation coded into the process or spontaneous? Or triggered by environmental changes, specifically more oxygen in the atmosphere (which did occur at that time)? Part of my reasoning is all of the hidden information in DNA/RNA code which is uncovered by mutation, error transfers, or new RNA activity. I cannot believe that raw inorganic material of the early universe could have converted into a monster coded program without design. - What George didn't answer in my questions about explaning the Cambrian Explosion, is how did it occur so quickly, without intermediate forms required by Darwin, knowing the mutation rates that have been established, even assuming they were doubled or tripled? My answer is in the RNA. To use the Darwin excuse of there was time for one step at a time is answered by Cambrian. It was one huge giant step in a short time with huge changes in morphology, and the arrival of new organ systems: for example, early forms had very simple neural webs, but it is quite a jump to a nervous system with a notochord, as in the Pikaia of the Cambrian.

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David Turell wrote: "What George didn't answer in my questions about explaning the Cambrian Explosion, is how did it occur so quickly, without intermediate forms required by Darwin, knowing the mutation rates that have been established, even assuming they were doubled or tripled? My answer is in the RNA. To use the Darwin excuse of there was time for one step at a time is answered by Cambrian. It was one huge giant step in a short time with huge changes in morphology, and the arrival of new organ systems: for example, early forms had very simple neural webs, but it is quite a jump to a nervous system with a notochord, as in the Pikaia of the Cambrian." - I thought I had answered this. It was in this "Truth of evolution" post: 
http://www.agnosticweb.com/index.php?id=735
"... the early Cambrian diversification opened up an exceptionally wide range of previously-unavailable ecological niches. When these were all occupied, there was little room for such wide-ranging diversifications to occur again, because there was strong competition in all niches and incumbents usually had the advantage." This suggests to me that the expansion was quick because there was no competition from existing life-forms. Even so it did take place over a very long time period, though shorter than is usual.

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David Turell wrote: "What George didn't answer in my questions about explaning the Cambrian Explosion, is how did it occur so quickly, without intermediate forms required by Darwin, knowing the mutation rates that have been established, even assuming they were doubled or tripled? My answer is in the RNA. To use the Darwin excuse of there was time for one step at a time is answered by Cambrian. It was one huge giant step in a short time with huge changes in morphology, and the arrival of new organ systems: for example, early forms had very simple neural webs, but it is quite a jump to a nervous system with a notochord, as in the Pikaia of the Cambrian."
> 
> I thought I had answered this. It was in this "Truth of evolution" post: 
> http://www.agnosticweb.com/index.php?id=735
> "... the early Cambrian diversification opened up an exceptionally wide range of previously-unavailable ecological niches. When these were all occupied, there was little room for such wide-ranging diversifications to occur again, because there was strong competition in all niches and incumbents usually had the advantage." This suggests to me that the expansion was quick because there was no competition from existing life-forms. Even so it did take place over a very long time period, though shorter than is usual. - Please note my quote above. I think it is quite clear that I am asking reasonable questions, and George is giving non-answers. The example of the Cambrian Explosion clearly challenges the Darwin step-by-step theory. George invokes 'unoccupied ecological niches' and lack of competition. Of course the niches were unoccupied, the organisms weren't invented yet by evolution. Are we to suppose there was a biologic vacuum and Darwin evolution got sucked forward?

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Loss of function is an adaptation to loss of need:

https://www.livescience.com/regressive-backward-evolution?utm_term=C3CFD69C-A485-4C10-9...

"In regressive evolution, organisms lose complex features and can appear to evolve "in reverse." But evolution doesn't retrace its steps, experts said.

***

"Regressive evolution involves the loss of previously evolved forms of complexity, Beth Okamura(opens in new tab), a life sciences researcher at the Natural History Museum in London, told Live Science. An extreme example comes from the myxozoans, parasites with very simple anatomies — no mouths, nervous systems or guts — and very small genomes. The simplest type "are essentially single cells," Okamura said.

"Long classified as single-celled protozoans, myxozoans eventually revealed themselves to be highly regressed animals, Okamura said. They evolved from cnidarians, a group that includes jellyfish, losing many features no longer needed in a parasitic lifestyle.

"Thus, myxozoans may seem, at least morphologically, to have returned to a previous evolutionary stage, Okamura said. "They're sort of converging on single-celled organisms," she said.

***

"Additionally, losses in complexity may accompany less-obvious increases in complexity, such as the biochemistries parasites use to get inside hosts, Okamura said. "It's very easy for people … to think of evolution in terms of what you see … what the morphological features are," she said. "But there are also lots of other features that we don't see at the physiological and the biochemical level."

"In cave fish, lost eyes may similarly obscure alternative complexity. Organs responsive to vibrations appear in great quantities in these fish, providing a way to sense in dark environments. And in the already-overstuffed head, these organs found available real estate in the fish's empty eye sockets, Jeffery said.

***

"Finally, experts cautioned that the term "backward evolution" may imply, misleadingly, that evolution has a goal of creating more complex forms. However, evolution merely favors features that make an organism more fit for a particular environment, Okamura said.

"In this way, regressive evolution is just evolution as usual. Losing complexity may make a parasite or cave dweller better adapted to its new environment — for example, by eliminating the energy costs of making a complex organ, Jeffery said.

""Evolution is always progressive in that it's selecting for features that improve the fitness of the individuals in which that variation is being expressed," Okamura said."

Comment: I believe this is a Darwinian by reasonable point of view.

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I have proposed that two models of evolution need to be considered: Darwin's natural evolution and designed evolution. Theoretically modification of mutations should allow evolution to reverse course. That is not what the record shows. It progresses to complexity, as if designed to do that. A new paper now shows that if one tries to reverse course at the molecular level, it won't work. It appears evolution cannot go backyard, although theoretically it should, being a random purposeless process (per Darwinism). The second link is a longer and more complete discussion. And finally a third link. Each gives differing quotes from some of the scientist's interpretations. An extremely important study!-
http://sciencenow.sciencemag.org/cgi/content/full/2009/923/1-http://www.sciencedaily.com/releases/2009/09/090923143335.htm-http://www.physorg.com/news172931418.html

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This is certainly interesting research, but hardly unexpected. Strings in my experience easily evolve into knots, and don't easily untie themselves. This is all part of the second law of thermodynamics. It seems there are "downhill" bits of evolution, like loss of sight in cave-dwellers, or strings knotting themselves, and "uphill" bits that go against the second law and need the ratchet to stop them slipping back. I don't see how this helps with your theory of "designed evolution".

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GPJ

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I don't see how this helps with your theory of "designed evolution".-As I have stated previously, there are only two possible ways that evolution advances, natural evolution (Darwin) and planned or designed evolution. Since we recognize that evolution always advances, either is a possibility based on the evidence we have, as I view it. The epigenetic process, meaning that we can see internal and external forces at work, implies that there are self-correcting ways to keep evolution on course to finally reach us humans, self-correction mediated from inside organisms. We humans are a very impressive endpoint to me. Since we have taken over so much control over the Earth, I have sort of had the thought that we may be the true endpoint, as some essays have discussed.-From a theistic standpoint, that all fits under a theistic umbrella. But I must agree that your naturalistic viewpoint has a good set of arguments to fit under its umbrella. Like dhw, I think it is a matter of faith either way, at this point in scientific research.

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