Timing of Various Eves and Adams

brennakimi, Yes, Thats why Ned sort of agrees natural selection not a factor in Michondrial mutations.

That doesn't follow at all, nor is it what Ned said. Ned agreed that there were genetic elements in the mtDNA which were not subject to selection to exactly the same extent that there are elements in the nuclear genome which are not subject to selection, i.e. non-critical non-coding sequences or third base wobble sites.In fact considering the elevated rate of mutation experienced by mtDNA and the importance of the correct mitochondrial metabolism for eukaryotic life there is a strong argument in favour of most of the mtDNA genome being under stronger selective pressures than the nuclear genome.TTFN,WK

There are many things which need to be done carefully to get correct dates. Saying that any number of things may mess up a date does not invalidate dating done correctly.I suggest you take this to the "correlations" thread in dates and dating. When you have explained what is presented there then and only then can you even hint that the dates are not accurate enough. No we are not. As someone explained just above this post. Carbon doesn't rot. This is incorrect. If I have an object sandwhiched between two undisturbed layers of volanic ash and the layer above dates to 150,000 years and the layer below to 180,000 years what possible reason would you have for saying that the object was not laid down between 150 and 180 thousand years ago?Before you answer I suggest you find about a bit about the geology involved in this kind of thing, the number of measurements made and the correlations between them all. The dating of varves is discussed extensively in the correlations thread in "dates and dating". You are wrong. We are not in agreement. Bacerial decay has nothing to do with this. You do not know what you are talking about. There have been papers presented that give some idea of the details of how the mtDNA was dated.Dating by the methods given is direct it is just not precise. Creationsists may agree or not but they have no never demonstrated any understanding of the processes involved so their opinion is of no value.

Just to confirm WK's post. No I do not agree.

--------------------------------------------------------------------------------Wounded King said: That doesn't follow at all, nor is it what Ned said. Ned agreed that there were genetic elements in the mtDNA which were not subject to selection to exactly the same extent that there are elements in the nuclear genome which are not subject to selectionGolfer says: Natural selection to a creationists is gene swapping between the parts subject to selection. How pray tell: do the evolutionists believe these asexual elements that are not subject to selection but are subject to natural selection? It appears your saying mutations is caused not by randomness thus its a selection. If so I agree, but this non-randomness mutations is not an example of natural selection. Right?

This should be expanded on somewhere. It appears to be gibberish. If you made it up yourself then to not say "to a creationists"! If you actually got it from some source then please reference that source. I suppose you are confused because we use the term "selection" when we mean natural selection. I would have thought that the context would make that clear in this case. They are not subject to any natural selection is what was being said. This is rather unclear too but guessing what you mean. No, I am not saying. It might help at this point if you would explain your understanding of the roll of mutation and selection in the evolutionary explanation. I have bolded that part because you seem to make a habit of ignoring questions and suggestions. Please be polite and helpful enough to start trying a bit harder. I have a guess at what you mean there but I don't think it is worth it to try to work it out. Please try to re-read what you write and attempt to make some sense.Nah, I'll have a go at it: There isn't any suggested "non-randomness" suggested. At least not in the way the words are usually used.Short micro lesson in the evolutionary model:
Mutations happen pretty much randomly (particularly in any way related to their affect on the organism). However the end result of evolution is that the remaining mutations are NOT random. They are the result after selection (natural or whatever) has taken place. SO the non-randomness of remaining mutations is an example of NS but the mutations themselves occur in the first place in a random fashion.If I have not made that clear enough ask. I'm sure others will attemp to word it in a way that you understand.In fact, I invite others to be more clear now.

When I returned home last night I had a pocket full of change. It was a random collection of change from purchases made during the day. That is mutation.After I selected all the pennies and put them in the penny jar I was left with a pile of change that contained no pennies. That is mutation after being filtered by Natural Selection.

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Aslan is not a Tame Lion

I can give it a try. There's a group of little black furry creatures living in the forest called Eutherians. One day, one of these is born with some brown specks on his coat. This was due to a purely random mutation. By sheer chance, these brown specks are an aid to camouflaging in the bushes. The bushes are brownish too. There are some big bad predators stomping around, but the one with specks manages to hide, and it reproduces. Some of the others also make it through to adulthood. The speckled Eutherian gives birth to a litter of six, and five of these are speckled like its parent. All these live and breed but the unspeckled one is eaten by predators before it can reproduce.If you go through enough generations, all of the Eutherians will be speckled whereas before they were all black. This mutation was beneficial. Other mutations are neutral. Still other mutations are detrimental. The ones that are detrimental don't last through many generations. Whether the neutral mutations last is purely a matter of genetic chance. Natural selection will filter out all the ones that are detrimental.If one of the Eutherians was born white, for example, and white allowed the predators to spot him easily, he would not last long enough to reproduce. So that would be one of Jar's pennies that doesn't go in the pile.

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"And from water we made all living things."-- The Quran

Hey robinrohan;Nice post - in case you're interested, your small furry mammal example has been investigated in real populations (though in the desert, not the forest), and the specific (beneficial) mutation pinpointed: The genetic basis of adaptive melanism in pocket mice. Nachman MW, Hoekstra HE, D'Agostino SL. Proc Natl Acad Sci U S A. 2003 Apr 29;100(9):5268-73. PMID: 12704245 I summarized the findings here.(edited to add link to paper.)This message has been edited by pink sasquatch, 12-14-2005 06:02 PM

Ned, I agree if you have an object sandwiched between two layers it suggests something to an evolutionists. Some creationists agree with you that Carbon in mineralized fossils can be dated between your sandwiched layers. The carbon ratio in a controversal mineralized wood fossil found in an Australia coal mine directly dated by C-14 suggests a problem with sandwich dating. I know that evolutionists don't trust dating of carbon that has been mineralized, yet just as amazing they apparently trust varve dating.Creationists likely will disagree with varve dating because of the mineralized carbonate contamination that the evolutionists believe contaminated the infamous mineralized australian wood fossil.If you believe in varve dating then you need to re-look at your belief in the australian wood fossil. It suggests a big problem with sandwich dating or more correctly with indirect dating of any inorganic layer to determine a fossils age.Are not bacteria and insects capable of digesting the wood because the carbon does rot(gets carted away as lunch)? RightIf one can not trust marine fossil dating for living creatures due to the carbonate problem how can one trust varve dating where organics are contaminated for large periods of time. You do believe wood rots and Carbon gets carted away for lunch. Don't you agree that the C-14 is translocated in the natural?I'll even agree that tree ring dating is likely calibrated to one annual varve per year. If trees averaged two annual rings like some creationists believe (spring and fall) then the 12,000 years becomes 6,000 years if C-14 is calibrated to tree rings.The dating methods of the evolutionists is the whole basis of your belief in the accuracy of random mutation rates of Eve. Right?The creationists see a big problem with your belief that indirect dating is direct evidence.You have the oldest human 200,000 years dated by rate of mutations in michondrail eve. Then by the same methods used for sandwiched dating evolutionists date Lucy (a chimp)to be millions of years old.The evolutionists picture just does not fit the evidence.

I read the summary, thanks. Can you define "receptor"?

Ned, Michondrial Eve asexual DNA is not subject to the same selections as the parts of the cell subjected to sexual natural selection.Natural Selection in sexual subjected mutated DNA is self correcting to the 10th generation in protected gene pools. This how breeders purge out defective genes in a new breed.How can natural selection purge out mutations in asexual mutations in Michondrial Eve. The only way I know is through death of the organism. Don't you agree?

This sems to be a word salad on the verge of making sense. But what breeders do is artificial selection a much cruder, though quicker, process than natural selection. That is what natural selection is, the organisms dying before having progeny, being infertile or less able to have progeny than other members of the population will not pass on their genes as effectively. Therefore genes which reduce these abilities will not propagate through the population, we say they are selected against.TTFN,WKThis message has been edited by AdminJar, 12-14-2005 04:52 PM

Sure (though if you want to discuss receptors and pocket mice too much further we should find another thread so we don't drive this one off-topic).Basically, a receptor is a protein that spans a membrane and transmits some sort of signal across a membrane. (Here is a link to a figure demonstrating how one class of receptors is thought to function). A seemingly endless variety of biological functions rely on receptors, including cell growth and survival, vision, blood pressure, and of course, pigmentation.Changes in the amino acid sequence of receptors can affect the "intensity" of signals - sometimes subtly, sometimes severely. An extreme example is some forms of cancer driven by receptors that get turned on "high" permanently by mutation, causing cells to grow out of control.In the case of the pocket mice I mentioned, the receptor Mc1r transmits a signal that ultimately regulates how much of the pigment eumelanin is made, and thus the color of the coat of the mice.I forgot to link the paper in my previous post, here it is freely available. Scroll down to the bottom to see figure one, to see what the mice and their habitats look like.I find it amazing that evolution was able to utilize mutation to "fine-tune" the color of the mice to their surroundings by "fine-tuning" MC1R signalling activity. Beautiful in its simplicity.

*Obsolete*This message has been edited by Wounded King, 14-Dec-2005 10:57 PM