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The Evolution of an Explanation of a Small-Headed Sea Snake

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I once debated an evolution professor who explained that evolution has tremendous explanatory power. But what exactly does this mean, and is it a good thing? Everyone knows that evolution explains that the species evolved gradually, but for new forms appearing abruptly in the fossil record evolution explains that the species evolved rapidly. Likewise, evolution explains that similarities in species derive from a common ancestor, but for species that are too distant evolution explains that the similarities in the species arose independently. Or again, evolution explains that biological variation is random and not intelligent, but for variation that responds to environmental challenges evolution explains that it created a fantastic adaptive machine that creates such variation. It seems that evolution can explain a great variety of outcomes, even opposing outcomes.  Read more

Jon Garvey Its fine and is indeed biological research to determine facts about the creature from its bones/fossils. Yes you are doing scientific investigation in coming to conclusions about this creature. However comparing your fossil to other fossils of different creatures or even types of the same creature and drawing conclusions about processes or descent or relationship has NOTHING to do with scientific research. its just drawing connections between fossils. One can not do research on the hidden process or relationship/descent. Its just lines of reasoning. Evolutionists and iD folks make this same error. Fossils are irrelevant to biological scientific investigation of origins. They only show what they show. Everything else is speculation even if true. So evolutionism is not doing scientific methodology in most of its research. A window of opportunity for error is demonstrated as a option by looking closely at methodology in these matters. Robert Byers
Robert - it depends what you mean by biology. I have a single ichthyosaur vertebra, and as a doctor am always amazed how much can tell me about the living animal, even though so long extinct: even something about its way of life. How it came to be an ichthyosaur - maybe less so. Jon Garvey
Yes its funny how evolution can be inviked to explain anything need explaining in the natural world. Yet they get away with this because of a point Mr Hunter brings up. The legitimacy of using a fossil record, slabs of creatures smeared in a moment of time, to draw biological connections between distant types of creatures. Its not the evidence that gets in the way of sending evolutionism to the ashheap of history but instead its the acceptance of the methodology behind the evidence. In short evolution has been getting away with saying they are drawing their conclusions from scientific methodology.when in fact they have not used this method of investigation but something else. ID folks do this too. Biology can not be done on rocks. Show how it can! Why Mr Hunter is the fossil record in ANY way relevant to scientific biological investigation? AS opposed to just clues from unrelated fields of study.! Robert Byers
Explanations at this level (all too common) are, indeed, explanations of everything and nothing. As Hunter points out, the "one way this could have happened" kind of explanation isn't Darwinian at all, but teleological - Larmarckian, if anything. So given this outcome, let's look at what availbale explanations there are. One assumes the original explanation actually meant something like: "some snakes had a smaller head and thinner bodies either by new mutation or recombination of existing genes. Being able to exploit a new food source provided a new selective pressure to divergence from being fat bigheads." Yet equally good would be: "some snakes produced a protein making them obsessional about delving in small holes, by new mutation or recombination. Therefore all except the smallest and thinnest died, providing a selective pressure..." etc. In the first case change is driven by structure: in the second by behaviour. Surely important to know which, but the theory gives us no help. Both those are adaptationist scenarios. But what if the real adaptation was, say, a tendency to more offspring, which was quite fortuitously linked to being slim and long, which are therefore merely "spandrels". The "obvious" adaptation story might be quite wrong: and without researching every possible difference and its contribution to survival, it's guesswork to say that the availability of new food has any (or certainly primary) survival value. Or, under neutral theory, maybe a whole pile of pseudogenes built up until, in a near-saltational event, a generation of snakes woke up to find they were long and thin, and unable to tackle the customary prey. Quite conceivable as the changes sound very consistent with Evo-Devo Hox type changes. Their only recourse is to learn to explore small holes PDQ - less adaptation than enlightened self-interest. Then again, without more research, what's to say the changes are not largely epigenetic, and completely reversible in a few generations if you only knew what environmental factor to change back (which likely wasn't just small holes popping into existence)? All these possibles are completely different from the Lamarckian explanation in the article. But suppose some kind of Neo-Lamarckian process exists like Shapiro's Natural Genetic Engineering (also evolutionary and naturalistic)? Some environmental stress like too many snakes and not enough big holes has the snakes purposefully throw up potentially useful mutations - bigger/smaller often does the trick, so that's targeted. Bingo! Some thin guys with small heads hit the jackpot and "rapidly evolved small heads to probe eel burrows." Isn't it interesting that the controversial teleological theory is the only one the just-so story actually fits? It would, of course, be quite possible to exclude some of the possibilities by a few years research, but that means the theory can't make assumptions about general cases. Each case has to be examined in detail before an explanation can be given. And that makes ET a theory with very limited explanatory power. Jon Garvey

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