Posted: Jul 05, 2010 8:10 am
by Rumraket
CharlieM wrote:I pose a question asking what must happen given that there is no functionless precursors (sorry for the double negative) in other words a function is assumed in all precursors on the path from common precursor to FlgE and its homologs. You then say my question assumes the precursor must be functionless. You must have read me wrong.

Fair enough, I misread your question as implying the precursor was functionless.

CharlieM wrote:But I'm not asking for a suggested pathway for every feature, just for FlgE. As homology is so prominant in Matzke's proposed flagellar evolution, surely he could look into the details of just one pathway as an example.

While it might be possible to look at the two proteins and propose a chain of events that happened in between, such an analysis would require huge supercomputer modeling of every step in the chain. This would be extremely expensive and time consuming. Additionally, even if you manage to compute the structure of an intermediary protein, it's still not a guarantee that you will be able to guess it's proper function since this will also require detailed knowledge of it's environment.
So in order to understand every step in the evolution of FlglE, you'd have to understand all the other proteins in the flagellar evolution too.

CharlieM wrote:You said it yourself, we cannot go back and witness these events. So to state that FlgE and its homologs developed from an unknown precursor through the selection of unguided random events is unfalsifiable and therefore not science as most here see it.

No, it's not unfalsifiable. The existence of protein homologues are a testable prediction of evolutionary theory and therefore their supposed nonexistance would falsify the flagellum evolution. This is because the mechanisms are observed to work in the here and now. Mutations/duplications/shufflings with selection acting upon them are an observed and confirmed phenomenon. From this an inference is drawn that the flagellum proteins evolved in the past. Therefore a testable prediction is made from this inference, which has the potential to falsify the evolved model.

Additionally, the evolution of the flagellum would be falsified if it had no genetic basis. That would also mean it was obviously "put" there by an outside agent. It would not specify what did put it there, but it would rule out an evolutionary pathway. Having no genetic basis, but still being present in an organism is actually positive evidence for some kind of "design". It means something other than the internal metabolism of the organism put the device in place. Now this could of course be anything from a virus to a superintelligent alien or whatever. But it would completely rule out an evolutionary model.

The problem with your design inference is that it is truly unfalsifiable. You could observe any feature and conclude it was the work of your designer.

CharlieM wrote:Several of these differences will have a minor or no effect in the function of the protein but there will be a vital few which make all the difference. Steps of single amino acid changes along the path are not going to result in a functional protein for every step. So in order to retain functionality, multiple amino acid changes will have to occur together. And changes will have been co-ordinated between the hook protein and related proteins such as hook associated proteins and regulators in order to retain a functioning unit.

You are making a number of claims here about the FlglE protein evolution which aren't nessecerily true.

CharlieM wrote:Steps of single amino acid changes along the path are not going to result in a functional protein for every step.

Are you implying that the changes are going to result in a protein with loss of function, or simply that the change was neutral and therefore did not result in increased functionality? In addition, I'd like to know how you know this?

CharlieM wrote:So in order to retain functionality, multiple amino acid changes will have to occur together.

This sounds like an implication that the intermediary might have resulted in a loss of function? This would obviously be false. Once again, you are speaking of events you can have no knowledge of?

CharlieM wrote:And changes will have been co-ordinated between the hook protein and related proteins such as hook associated proteins and regulators in order to retain a functioning unit.

So you did those supercomputermodelings? Fascinating. Please share your results.

CharlieM wrote:A few evolutionary facts have been given which I presume are supposed to argue against my position. The ones I can recall are:
A monkeyflower turning into a monkeyflower, a peppered moth turning into a peppered moth and hydrogen producing bacteria turning into hydrogen producing bacteria. I have no problem with these examples of evolution.

Hahaha... the micro/macro evolution canard.
And you are arguing against a bacteria without a flagellum evolving into a bacteria with a flagellum? Great. Sounds like a double standard to me.

It's also worth noting that you more or less ignored the fact that these provided examples directly demonstrate the ability of random mutations with selection acting upon them to result in new and/or increased functionality. You know, the thing you originally specified you had a problem with?

CharlieM wrote:So to answer your question, I see the diversity of organisms as the individual expression of archetypal forms and not as blind accidents of natural evolution. I have no problem with evolution as such, just with blind, unguided evolution.


CharlieM wrote:It is blind to the future and, because it only "sees" present fitness, it reduces the variability of the breeding population. Some trait which may be beneficial in a future environment gets weeded out because it is of no present use. So natural selection tends to reduce the variability of the breeding population. A bit like stem cells becoming specialized.


No, what you obviously have a problem with is the fact that you are an ape like the rest of us. You may wish all you want that someone superintelligent made you for a "special" purpose", whatever that is. But the simple fact is that you evolved and noone was around to guide it. You're an ape, get over it. Life can still be enjoyed, you still have a right to live, and nobody thinks any less of you because of it.