A problem with molecular evolution?

but we do know that at least now they need each other. and we know that for about million such cases. so the burdon of proof is on someone who claim that such a system can evolve stepwise, and not the opposite.

And we do know that things that depend on each other can evolve by having different ancestral functions, so that fact alone does not represent any challenge to evolution.

So the burden has been answered in principle, you’re just demanding we show how everything evolved. Suppose I answer for the evolution of porphyrin biosynthesis pathway you’ll just move on to some other thing and demand that be answered too. If we don’t know everything, then (to you) we don’t know anything.

And so we’re left chasing the goalposts until the end of time.

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It is only problematic for the claim you made in the opening post. It isn’t problematic for evolution.

The production of aldosterone is a new function, and our whole point is that IC systems are not always IC when they emerge.

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we dont know that but assume that. so again: we assume against reality here.

actually no. you only need to show how even a single complex IC system can evolve stepwise.

if we will remove the aldosterone what will happen to the creature?

Do you accept that producing aldosterone was a new function?

if we believe in evolution? of course.

So we have a new function, and the new steroid bound to an existing protein. Problem solved.

not if the creature cant survive without it. in that case i will ask how he became dependent on it. in addition, i will ask how the first hormone/hormone receptor ever evolved.

You can remove whatever genes or interactions that stop them from being dependent on the new steroid.

I suppose that you won’t believe that the Romance Languages evolved from Vulgar Latin unless we can show you the first human that used language.

so we need to believe that at least one hormone (the first hormone ever) appeared at the same time with its hormone receptor?

No. Why would we? As we see with aldosterone, there can be a new metabolic pathway that creates a new small molecule that can bind to an already existing protein.

We do know that. We’ve literally watched it happen in real time in the laboratory(Cit+ phenotype in the LTEE, for example). And many such events can be reconstructed by phylogenetic methods to show that, in demonstrable empirical reality, the inferred ancestors were functionally capable of contributing to the fitness of living organisms, and how mutations altered their functions so they became dependent on each other for their later functions.

That’s what was shown in all those ancestral sequence reconstruction articles I’ve linked. They show how systems that consist of two or more things that today depend on each other to function, used to consist of fewer things, that these fewer things functioned in a different way back then, and they show HOW they changed and acquired their modern functions through mutations and selection.

So no, you’re just blatantly wrong. YOU are denying reality here.

We have done so in principle. That’s all that is necessary. I don’t need to count to a million to know that I can do so because I can count to 100, or 1000.

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The blood clotting cascade is a supreme example of things depending on each other having evolved from each other.

http://www.millerandlevine.com/km/evol/DI/clot/Clotting.html

actually no. you only need to show how even a single complex IC system can evolve stepwise.

That’s exactly what Miller and Levine did for what Behe claimed was IC - Behe claimed the clotting cascade was IC.

i dont think so. again, if we will take the Heme example, its clear that not every step is functional by itself:

Dude.

My argument wasn’t on heme.

It was on the clotting cascade.

You know, the one from which plasminogen, plasminogen activator, factor IX, factor VII, factor XII, factor X, prekallikrein, antithrombin, antitrypsin, and more all evolved from a serine protease.

http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.876.6327&rep=rep1&type=pdf

How did you determine that every step in a synthesis pathway was never functional at any point in history?

That’s not clear at all. You just say this.

You do understand that heme is just one of many porphyrins present in various organisms, right?

so how this supposedly happaned? what was the first step in blood clotting and how many mutations required to get the first blood clotting system from something that was not a blood clotting system?

i cant. but we cant also prove the opposite, and we have good evidence that the opposite is nearly impossible.

Then we can ignore this statement: “its clear that not every step is functional by itself”

What is left of your argument once that premise is removed?