Posted: Jul 06, 2010 12:39 am
by CharlieM
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.

Quite right, tinkering with one protein on the path affects the whole system. Its a bit like a Rubic cube only vastly more complicated. I'd say beyond the capabilities of unguided forces.

The existence of protein homologues are a testable prediction of evolutionary theory

Protein homologues give us a clue that the proteins are related and were possibly derived from the same source. I have been told constantly that the path is too complex to work out. So how do we know that naturalistic evolution is the means by which the path is crossed or is even capable of negotiating that path? Must I just take it on faith? Just because we observe mutations/duplications/shufflings does not mean that they are unguided. If DNA replication is the result of an accident where did the error correcting mechanism come from? "Repair proteins appear to efficiently scan the genome for errors by jumping like fleas between DNA molecules, sliding along the strands, and perhaps pausing at suspicious spots, say researchers at the University of Pittsburgh, the University of Essex and the University of Vermont who tagged the proteins with quantum dots to watch the action unfold." - ScienceDaily Mar 14 2010.

Pierre Paul-Grassé:
In sum the mutations of bacteria and viruses are merely hereditary fluctuations around a median position; a swing to the right, a swing to the left, but no final evolutionary effect.

I 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?

The amino acid sequence of FlgE is far longer than its homologs and so gene duplication and joining is the proposed path in its development. This involves more than a single step so I'd be surprised if anyone believed that a sequence of functional proteins in single steps occurred.

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

Well Matzke proposed the path so ask him. Although the search space that naturalistic evolution needs to sample is so large that it would indeed take a supercomputer to find a way through.

I 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.

Why? With the flagellum we have a novel structure with a new function, with the others we don't, unless you want to stretch the definition of, "function". And besides that is not what I'm arguing against.