Thanks for replying.
Fade said:
Asking questions that have already been answered by science and then pretending that they haven't doesn't strike me as being particularly Scientific. Like I said before, the evolution of the hinged jaw is pretty well documented. If memory serves the theory goes that it had something to do with gills in early jawless fish. try googles book search.
The problem I am talking about is a legitimate question, even to this day, and no amount of saying 'it's well documented' is going to give an answer that doesn't yet exist. Scientists are still trying to figure it out, and although there has been plenty of speculation, the ACTUAL intermediate jaw is unknown. The best attempt I've seen so far to explain it from a combined genetic/mechanical view can be found here:
http://pharyngula.org/index/weblog/comments/evolution_of_the_jaw/ At least they have the balls to admit that it's still hypothetical [the word appears several times]. My take on this piece is that it requires a lot of mutations that aren't good candidates for selection until a great many generations when suddenly they are again. Seems a touch extraneous, but not impossible. However, given the small number of genes involved and the fact that things are growing out into nowhere, it's easy to see that this one is pure speculation, especially when extra complexity is added downstream, ie: which came first, the jaw or the teeth? Hard to see how selection is going to be able to move forward with this model, so many features rely on other features it's not funny. There is an overwhelming desire to explain how one fossil got to another fossil, and whether it's proven or not, the explanation is ALWAYS accepted if it is logical. That's not what I call science. And after all that there is still no sign of an intermediary geometry, and certainly nothing like an explanation of how an irreducible geometry like an inline twin-pivot hinge can be selected from the available options. I would apply similar principles of argument to the inner ear, another specific geometry. [perhaps we had a different mechanism and the modern inner-ear took over later on? I'd find that much more acceptable].
It is common knowledge that issues like these are not fully understood. Consider this statement: "The development of the jaw is one of the most significant evolutionary events in early vertebrate history. Little is known about the jaw's origins, however, due to a poor fossil record of the critical time when the first jaws evolved, sometime before the Devonian period (412 - 354 million years ago). " It came from here:
http://www.amnh.org/museum/press/breaking/jaw.html and is far from atypical.
To believe something to have truly have evolved from one thing into another thing is not proven by two different fossils. Prove me wrong on that.
Fade said:
I just threw up a little...
Get well soon:hug:
JerryL said:
Replication errors (which have a variety of influencing characteristics, mostly chemical), transposition errors, viral insertions, etc. ...Sickle-cell gene ....Evolutionarily speaking, when did the last "new" organ appear?
The usual stuff, yeah, I know. Now, what is the mechanism that makes something get a new organ/function? Look at what they can't do! We'll use the fruit-fly as an example. There are over 2900 mutations documented for this little baby and they've been trying all sorts of things on it for years, including bombarding it with x-rays. You'd think that there would be at least one sign of change towards something else, but it's still totally a fruit fly. The variations have all been fruit flys, some ugly, some pretty, but all fruit flys. Why no drastic changes? These things are getting plenty of gene altering influences, maybe more than they would ever get in the field. There was one with four wings [a repeat of existing dna, like an extra finger] but it apparently could hardly fly so it would've been less selectable anyway. Given the sophistry of even the simplest dna [there are many error-checking and correction mechanisms built into dna/rna as I'm sure you know] and the fact that we can't do it in the lab with full control of the conditions, then how can anyone expect me to believe it could happen in the field. What's the mechanism if it did? I need proof, not speculation.
The interdependancy in even the simplest animals is an even bigger problem. It's not yet been shown that you can mutate a control gene [which theoretically could change the phenotype] without ruining the animal. Doesn't anyone have the common sense to realise that if this had been done there would have been a storm of excitement and we'd still be hearing about it? So, provided you figure out how to do the kind of mutation I'm talking about, the problems may in fact multiply. I'm looking for really new genetic information, not old information to be rerouted to produce variatons of the existing animal. New animals means Selection must have something new to choose from.
JerryL said:
Mutation is not a random process, it is a chaotic process. You are contradicting your earlier statement that physics is the underpinning of the universe by asserting that it's random.
"Mutation: Random change in the genetic code."
http://www.micro.utexas.edu/courses/levin/bio304/popgen/mutation.html
It's certainly seen as random. And what makes you think you can't apply a predictive operation to a chaotic event? The case here for an application of quantum-probability is a good one.
JerryL said:
Of course there isn't. That's why abiogenesis is a hypothesis and not a theory.
I'm glad we agree on something :clap
And so...
I look at the theory of evolution and I grow more and more weary of the universal dismissal of anything that looks different. I remeber how I was sad to hear that when they dug up a T-rex last year with tissue on[in] the bone the first things they were concerned with was how it got preserved : "These factors, combined with as yet undetermined geochemical and environmental factors, presumably also contribute to the preservation of soft-tissue vessels." [
http://www.sciencemag.org/cgi/content/full/307/5717/1952 ] NOBODY even thought to say that it might be younger than expected. [Also notice they haven't got a clue as to how it got preserved]. I mention this one because it shows that even when they dig up a T-rex with tissue that looks like it just died they still automatically attempt to turn the situation around to suit the theory. All facts happen to fit the theory you know. Surely someone with an open mind could've said "Let's think about this from all angles just in case we're wrong". But no, science has lost it's frontier edge. It's all academic now folks. I stand by my first post when I said that I don't believe in evolution like I do in gravitaton. Evolution is neither here nor there for me now. I will continue looking into it but I refuse to be a sheep and accept it as a done deal. I've accepted parts of it in my earlier posts, but the feeling I get is that the overall theory itself is missing something; there are just too many questions for my liking.
Work is really catching up with me so it'll be quite a while before I get a chance to post again. By all means have the last word folks, I'm not here to atttack anyone. Thanks all for trying to help me.
