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Debate:How should we view the fact leading scientists do not believe in God? (view source)
Revision as of 04:50, March 24, 2008
, 04:50, March 24, 2008no edit summary
:Most of that post is simply assertion. When Darwin proposed it, much of it's opposition came from scientists, so I'm not sure that they ''were'' convinced that quickly. Of course it has never been observed—but as it hasn't been, then it's taken on ''faith''. The "extrapolation" may have sounded reasonable in Darwin's time, but genetics actually shows that the extrapolation is invalid. All the ''observed'' mechanisms for variation do ''not'' introduce new genetic information, but tend to destroy it. Yet scientists "extrapolate" from this destruction of information to ''generation'' of information! That's not extrapolation—that's ''blind'' faith (i.e. faith ''contrary'' to the evidence). [[User:Philip J. Rayment|Philip J. Rayment]] 07:59, 28 February 2008 (EST)
:Most of that post is simply assertion. When Darwin proposed it, much of it's opposition came from scientists, so I'm not sure that they ''were'' convinced that quickly. Of course it has never been observed—but as it hasn't been, then it's taken on ''faith''. The "extrapolation" may have sounded reasonable in Darwin's time, but genetics actually shows that the extrapolation is invalid. All the ''observed'' mechanisms for variation do ''not'' introduce new genetic information, but tend to destroy it. Yet scientists "extrapolate" from this destruction of information to ''generation'' of information! That's not extrapolation—that's ''blind'' faith (i.e. faith ''contrary'' to the evidence). [[User:Philip J. Rayment|Philip J. Rayment]] 07:59, 28 February 2008 (EST)
::I have to disagree here - genetic variation rarely introduces or destroys genetic information - it, more accurately, mangles it. Usually you get two results - missense and nonsense. Missense is something that reads incorrectly - usually something small, like a substitution of one base pair for another. It can have no effect, or be harmful or beneficial. Then there's nonsense. Nonsense is when the resulting genetic code is totally, completely unreadable. This usually occurs when you get a frameshift mutation - since genes are read in codons of 3s, adding one or two base pairs or deleting one or two will 'shift' every single base pair down the chain. This results in more dire genetic disorders. Now, how this relates to evolution: missense is actually a good thing: it can introduce new alleles (variations of a gene - usually just dominant/recessive) into a population, add new genetic strings, duplicate a chromosome, etc. So long as it doesn't result in that organism being infertile or dying, it will cause a change that can be compounded in its successors. Lots of evolutionary trends can be explained by gross mutations that, by a quirk of luck, did not end up killing the organism. The best example I can think of is the duplication of the hox gene (a homeobox gene; it determines how body segments develop) in invertebrates. As you go from invertebrate to vertebrate, you find more and more copies of the hox gene; invertebrates have one, simple vertebrates have two, vertebrates with seperate, complex jaws have three. These large mutations, when they don't kill the mutant, can be passed on and slowly, gradually edited via trial and error until you have an astonishingly interesting result. The best example of genetic information being "introduced" and resulting in a beneficial (to the organism) evolution are antibacterial resistant disease strains; bacteria reproduce at an incredibly fast rate, and as such a bacterial population has quite a few different mutations and alleles in its gene pool at any given time. As such, when you expose the population to waves of antibiotics, the tiny fraction of bacteria that survive by a combination of luck and good genetics pass these genetic changes onto their offspring. Not only this, but bacteria can also pass the genetic changes on to other, non-related bacteria by conjugation and plasmid exchange. Anyways...Yeah. Kinda run out of steam, but there's a shortish explanation of the mechanisms I believe power evolution.--[[User:Reasonless|Reasonless]] 00:50, 24 March 2008 (EDT)
::I don't see where the "assertion" is. I'm probably wrong about "quickly", I concede, but the fact is that evolution has been accepted, and for the reasons I state. Plus of course the evidence in the form of fossils. [[User:Humblpi|Humblpi]] 08:16, 28 February 2008 (EST)
::I don't see where the "assertion" is. I'm probably wrong about "quickly", I concede, but the fact is that evolution has been accepted, and for the reasons I state. Plus of course the evidence in the form of fossils. [[User:Humblpi|Humblpi]] 08:16, 28 February 2008 (EST)