Djevv said:
Why? Good question. Perhaps God tweaked an original flagellum design to make it useful in many different species
. Perhaps He is a keen molecular engineer and wondered how many viable flagella He could make
. Perhaps Devolution has modified an original flagellum in different bacteria by essentially natural means
. Perhaps God got carried away with an artistic urge when it came to flagella
.
Is it more reasonable to believe that each flagellum from each prokaryote was individually evolved by each species? Sorry, I am tempted to commit the incredulity fallacy again :hihi.
So on one hand we have an god (with no real evidence of their existence) showing distinct signs of OCD and this is but one of the billions of examples of convergent evolution, let alone imperfect design, vestigial features and the existence of pathogenic organisms (whatever for?).
On the other hand we have the evolution of a basic sectretory system (which shows evidence of having become widespread via horizontal transfer....that is between species) which has evolved in different lineages and niches in different manners into flagella for motility. All of these systems share the core proteins that are found in the secretory system, but then have evolved different ways of generating motility via the flagella. That is exactly what evolutionary theory predicts! A number of different solutions to the same problem, each evolved seperately and each selectively advantageous to their respective species. No need for any incredulity here.
A form would be a functionally viable individual that has a selectictive advantage. I'll make sure that genomics reading goes on my 'to do' list
.
I was interpreting your term "form" to mean species. We generally look at traits as selectively advantageous producing the species adapted to their particular environmental niche. Depending on how closely related the two species are the actual molecular differences between them can be quite minor.....over time these become greater due to random genetic drift and the lack of gene flow between the two species.
OK, but does the demonstration that a simpler system exists that might be co-opted to form a flagella mean it is definitely able to be assembled stepwise with all fully functional intermediates? The point here is is that it is not difficult to invent a somewhat plausible story about how a complex machine like biological structure possibly formed as long as some of the the details are missing. This might have occured, we infer that this must have happened. Is a somewhat plausible story enough to prove that evolution produced a structure which to seems to require a certain number of functional parts to all work together? I think it remains a somewhat plausible story, and no more.
This is shifting the goalposts though. The criticism that ID proponent made was that some biological systems
couldn't have evolved via Darwinian mechanisms as they are too complex and required too many cooperating parts (ie. irreducible complexity). This research doesn't aim to necessarily prove how they evolved, just to show that they are 'evolvable'. Examination of the individual proteins in these systems can provide insight into the 'how' though and the timing of such events. The fact that you claim that is plausible defeats the ID position.
Isn't it easier to imagine that a a TTSS system that is useful for only a minority of bacteria might have developed from a working flagellum? Certainly it is possible.
Yes, it is possible, although the evidence presented in that paper makes it far less likely. Examination of the proteins making up TTSS systems and bacterial flagella, strongly suggests that the TTSS system is more ancient than the flagellum.
I read the article, but not in the kind of detail you need to fully comprehend the force of the evidence and arguments, so not being and expert in the field I won't comment except to wonder about this section:
'Second, the suggestion that a simpler system
(TTSS) is derived from a more complex system (flagella) is
quite odd in an evolutionary context since it runs against the
progressionist grain that pervades evolutionary thought
since the days of Jean-Baptiste Lamarck. As was pointed out
by Aizawa (2001): “The flagellum is a beautifully designed
architecture almost completed in evolution. Why should
those sophisticated skills be abandoned to go back to boring
soluble proteins?”
This seems to be indicating that the paper has an a priori progressionist evolutionary bent that it wishes to promulgate.
To be honest, I didn't particularly like that section in the introduction either. It was unneccesary and didn't add anything to their argument. That aside the actual research presented in the paper clearly demonstrates that the TTSS is a more ancient system than the flagellum, based on analysis of the proteins that make up these structures.
I agree, natural selection ought to have taken care of this creature at its inception, but it didn't. Why?
??? Um, the bombardier beetle
doesn't explode and the system is advantageous and has become fixed in the population. Any of these beetles that generated a system that led to self destruction wouldn't survive to pass it on! Only those that had a workable solution survived and passed on the adaptation.
Well, the Bible is the revelation you were after. I know that is not original thinking on my part, but it is tried and tested.
To me all roads in life hinge on the question, who do you say Jesus is. Can you answer that question?
However there are serious questions over the stories in the Bible. How can you tell the difference between literal truth and allegory?
Why do you think the Jesus question is confined to Christian cultures? I know that sounds stupid, but the lives of individuals in other cultures hinge on other questions with equal validity to yours. This is the problem with faith-based positions.
Finally since the topic is intellectual honesty - do think it is honest of ID proponents to question evolution in terms of irreducible complexity. I agree they have not proved their case, but I don't think it is dishonest to try.
No, irreducible complexity is a valid hypothesis that has been discredited, and like all discredited scientific hypotheses must be discarded. Some of the actions of the big 'players' in the ID world though are clearly dishonest, ranging from partial presentation of facts, distortion of evidence, misrepresentation of their goals (to get creation 'science' back in the classroom), quote mining amongst others.
BTW I am still waiting to see any evidence contradicting evolutionary theory.
