"Best" evidence for evolution.

Various ways a chimp foot COULD change into a human foot. But it doesn't happen, right? If it did it would be a deleterious change. Chimps need chimp feet, not human feet. And that's another expression of the problem with the whole evolution scenario I'm trying to pin down. There is no set of mutations that would get you a viable transition, you'd get useless body part changes, deformities. Yes it sure LOOKS LIKE there's so much similarity that getting from the one to the other should be a pretty simple matter. But really, you need changes in a particular direction that just aren't going to happen on the random scheme mutations occur, and you need bazillions of them, changes in the position of the bones, changes in the shapes of the bones, changes in the leg bones and muscles, changes in the way the foot ambulates, connects with the ground -- cuz those soles do not look like human soles -- and that's just the feet. The whole body has to get changed by these totally unreliable unpredictable mutations, and all in a way that changes one body whose parts articulate together so nicely, into a different body whose different parts articular together nicely in a completely different way.You certainly don't need a human foot until you have a human body with the ambulatory needs of a human body and that means you need changes throughout the entire body design to occur ina particular order in a particular time frame.Edited by Faith, : No reason given.Edited by Faith, : No reason given.

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"An environmental response?" Sounds rather Lamarckian though I guess all you mean is that a slight adaptation along those lines had survival value so it kept being selected. But that's pretty much what I said myself. it has to appeare in the first place though, that's the hard part to account for.

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No, it isn’t Lamarckian because it isn’t evolution. I’m suggesting that it’s just a feature of the species that they develop slightly differently (in growing up) because of the environment. And I’d mark their diet as the most plausible difference.

So, to review, these are all the same, just different shapes. And these, too, are all the same, just different shapes. But these are completely different and totally unrelated because they're different shapes. Hard to take you seriously if you're claiming that with a straight face.

Please show picture of intermediate hominid feet.

I can try to be more specific to deal with your debunkery but it gets tiresome. It's hard to use words as precisely as you are requiring of me.

I'm not trying to catch you out in some kind of wordplay and sophistry. This isn't a trick. Those trilobite pygidia are more different from one another than the bones of chimp and a human foot are. This is just obvious.But whether we agree on the degree of difference is not important. The important thing is that we have all the same bits. For a mutation to change the shape of bits it just needs to make a change in the speed, or the start or end, of a molecular process during development. The same as what causes dogs to have such a weird variety of shapes. OK, now I think I understand the objection you were trying to make. You're simply arguing that no intermediate form could be viable - you have to have the whole package at once.But that's not true. I unfortunately don't have a good hypothesis for you, since I don't have a good explanation for human bipedality, but the bits do not have to all come at once. You could walk upright with a chimp's foot. It wouldn't be as efficiently as we do, but that very fact is what would create the selective pressures to change the foot once the shift to regular bipedalism has already happened - most of the changes in the foot would probably follow the changes in the pelvis.I think it's common to underestimate the behavioural flexibility of many animals. Animals can, and do, do all sorts of things they are not particularly well designed for. If this allows them to exploit an unexploited niche, then they can succeed at it despite not being very good at it. Being in a situation where there's a mismatch between anatomy and behaviour creates a selective pressure for change in anatomy - things that could have been deleterious previously could not be beneficial. And once one thing changes, it then puts pressure on other things to change so as to work better with the changed bit. Which might then put pressure on other bits to change, or which might allow the original change to be pushed further.

duplicateEdited by dwise1, : duplicate of Message 353

Australopithecus. Also the Laetoli footprints. Look it up.The feet seemed to change first, so even with Australopithecus they were most of the way there.Edited by dwise1, : Laetoli

duplicateEdited by dwise1, : duplicate of Message 355

Already answered in Message 337. Stop ignoring it.

After some time to think about it I think I was having a problem with your emphasis on "shapes" as if I'd used that word in that general a way. That's what I meant about having aproblem with the words. I don't remember exactly unfortunately but I don't think I used the word "shape" in the way it would apply to the trilobite pygidia but since you took it that way I got confused. I remember referring to the shape of the toes or fingers or thumb of the chimp hand or foot as being a problem for evolution from chimp to human, the idea being it isn't just the fact that the basic bone arrangements are similar that has to be taken into account in thinking about evolution, but that the shape of the flesh itself is so different it would require a lot of mutations to make the change.The only other time I might have used the word "shape" might have been to describe the typical trilobite shape, the oval disc like shape, but I don't remember for sure.In any case the many different shapes of the pygidia in your illustration could all be produced by the same genome it seems to me since it's just a matter in that case of different combinations of genes bringing them about and it's all a sort of clumping of the spines at that point.Same of course with the dog skulls, which we KNOW all come from the dog genome. Same cause in different genetic combinations. Such changes are brought about within a species genome by reproductive isolation of a new set of gene frequencies. That brings out new genetic combinations and new phenotypes.But the genetic stuff has to already be there for such new combinations to occur. And when it comes to chimps I don't see that the genetic stuff for anything human is already there. yes the basic bone structure is similar but the proportions of the body are completely different and the fleshly parts are very different. The chimp foot is too different from the human foot for it ever evolve into that kind of foot. And the only way it COULD ever do that is by multiple mutations, trial and error, as I keep arguing.That is how I've been thinking about all this anyway. Edited by Faith, : No reason given.

Changing the shape of the bones changes the shape of the rest of the tissue as well. The development of these things are not separate - you don't need one mutation to change the orientation of a thumb bone and a separate one to change the orientation of the overlying skin - the same changes to signalling molecules will affect the development of all the bits of the limb.If you mean that the structure of flesh is different, then you're right, but in what way? The myosin fibres that make up chimpanzee muscle are almost identical to those that make up human muscle. The main difference between human and chimp muscle stem from the fact that proportions of different types of myosin. There are three main myosin molecules that make up both human and chimp muscles. Chimp muscles contain a pretty even amount of all three, while one of the three, MHC I, makes up more than half of human muscles.The genetic basis of this difference is apparently not known, but doesn't need to be anything too complicated. These different fibres are produced by different (but related) genes, and like I already mentioned, there are lots of ways to change genes, or their promoters or inhibitors, to make them produce more or less of their product - the products in this case being muscle fibres.The differences in tissue between humans and chimps are just as much a matter of shuffling of parts as are the differences in the position of bones. There's a lot more difference than 'clumping of spines'. Half of them don't even have any spines, and yet are noticeably very different from one another. You've mentioned your having problems with vision - can I recommend zooming in to see them properly?I would be extremely surprised if they were all constructed from identical tissue, but that's probably very difficult to tell from fossils. But I'm more interested in how you can tell these can all be produced by 'the same genome'. What's your criteria for figuring this out? Dog skulls all came from dog genomes yes, because they're all dogs. But 'the dog genome; is an abstract concept - there isn't really any such thing. Every dog has a DNA sequence unique to itself.And we know that sequence can change - by mutation. This isn't speculation - it's fact. Dogs have probably had their genes sequenced more than any animal other than humans and the classic laboratory subjects for genetics like D. melanogaster and C. elegans; so we can see that dogs have some sequences in their DNA that were not inherited from their parents - mutations change DNA sequence - indisputable fact.And we know that changes in DNA sequence can have phenotypic effects. We've identified many in dogs. The weirdly shaped face of a modern bull terrier is likely due to a unique tandem repeat sequence in the Runx-2 gene, this doesn't exist in other breeds, and it doesn't exist in the DNA of a bull terrier which died in 1931 (and we know from old pictures that bull terriers then did not possess the same weird facial shape). It seems likely this is a mutation that arose in this breed in the 20th century; and it causes phenotypic change.If DNA sequence can change by mutation (which is an undeniable fact) and if changes in DNA sequence can cause morphological change (which is an undeniable fact) then mutations are causing morphological change. The shape of the bull terrier's face was not already hanging around in the genome if the specific sequence that caused it did not previously exist.

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But I'm more interested in how you can tell these can all be produced by 'the same genome'. What's your criteria for figuring this out?

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In her ignorance Faith decided that all trilobites were the same species. Therefore they are. That is all there is to it.The fact that this makes her look worse than admitting to her original mistake is something she is unable to understand.

I mean the SHAPE of the flesh is different. They are all trilobites, all with the same basic parts to them. I'm a creationist, I don't divide anything into separate species if its got all the same basic parts to it. Goats are not horses, they don't have the same basic parts. Four legs isn't what I'm talking about. What makes a goat a goat and a horse a horse is what makes them two separate species. Yes I'm sure you can come up with all sorts of creatures you don't think fit my definition and I'm sure I can say which are species and which aren't because I think it's obvious. arring a very occasional one that's hard to identify. All I'm doing is trying to see things from the creationist point of view.

I know, it's all about how portions of populations have different sets of gene frequencies. It's hard to sort all this out of course, but although there isn't a simple "dog genome" I'd guess you won't find a dog's genome that looks like a duck's or a cat's. No argument. Of course. I know mutations make changes. What I claim is that there could never be enough of them making enough of the right kind of changes in the right places to change one species into another. All the mutations you say you can identify that would be needed to change an ape into a human being couldn't happen in any kind of numbers or patterns to accomplish that feat. Yes. Luckily some that the creature can live with. OKEdited by Faith, : No reason given.