From Panda's Thumb: The Evolution of T-URF13: Does Irreducible Complexity Count or Not?

Notable mentions of @Art and @NLENTS. Also relevant to an ongoing discussion in another thread.

The Discovery Institute, principal advocate of the Intelligent Design (ID) movement in the US, attempts to invalidate scientific results demonstrating that so-called irreducibly complex (IC) biological traits can evolve naturally. According to the ID protagonist Michael Behe (1996), a system is by definition irreducibly complex if it consists of several specifically interacting components which together produce a function such that the removal of any single component leads to the failure of this function. Most biochemical systems are irreducibly complex in that sense. Since they cannot be less complex without losing their function, unguided natural processes based on random mutations and selection cannot build them up gradually, according to Behe. Instead, multiple coordinated mutations would be required simultaneously .


From the article:

I and many others have been making this same argument.


the same argument, and for a considerable length of time.

This is a very nice complement to the recent publication by Jason Rosenhouse on The Failures of Mathematical Antievolutionism, which arguably provides a singular stake thru the heart of C / ID.
But will any of this matter? Will the Discovery Institute finally shut down their mini-industry and send everybody home? Nope.


But it’s not necessary to reach a given target, that is why the probability is calculated.

But since it actually happened, the probability of this specific event equals 1.

With the timeframe considered after the fact.

Literally any event can be calculated as improbably as you wish, after the fact.

No, before the fact. And events can be probable, or improbable, before the fact.

That’s a problem for you since you’re the one doing probability calculations for things like eyes and flagella now, after the fact.


I like how we have an ID-creationist in this very thread arguing in multiple threads that what occurred in reality somehow can’t happen.

T-URF13 evolved, has multiple protein-protein interactions, and is irreducibly complex. All supposedly things that shouldn’t be able to happen. :man_shrugging:


No, I’m saying that the point of view adopted in viewing an event is important, before the fact (which is really the only point of view of interest) or after the fact (where the probability is 0 or 1.

But did multiple protein-protein interactions each evolve? That is where Behe places the edge of evolution.

If the probability is 1 after the fact, what can doing a calculation where you imagine the event before the fact hope to accomplish? It already happened.

We can view your own existence, with the particular genome you have, “before the fact” 10 generations ago. Then we do the compound probability of the roughly 100 mutations that is added each generation and we get some utterly fatuously low probability like 10-10 000 000 that your particular genome should happen to result after ten generations of mutation and genetic recombination. What have we shown, that you can’t have ten generations of ancestry? That you shouldn’t exist? What?

Yes. A membrane pore consisting of multiple interacting subunits, regulated by an intracellular signaling molecule, must be able to assemble into that pore system in the first place (which requires that each subunit has at least two binding interfaces through which they stick together). And it must have a binding interface by which it is regulated by some intracellular signaling molecule too.

Could it be that protein-protein binding spots just aren’t so rare or difficult to evolve as Behe assumes?

BTW: You are describing Bayes Rule (Bayes Law). There’s a formula for that.

This finding specifically refutes Behe’s argument from Irreducible Complexity, not some of the other arguments that he might have later attempted. Unless you, or someone else, can provide a good reason that this finding does NOT refute Irreducible Complexity, we should consider it refuted.


@lee_merrill is doing probability calculations? Did I miss something?

I suspect he’s only claiming that probability calculations can be done, but not actually doing any. Because as was demonstrated here (and here), he can’t do the calculations himself.


I does not for several reasons:
Irreducible complexity targets the Darwinian mechanism not genetic recombination.
The Turf discussion is around a single gene as @lee_merrill mentioned.
Irreducibly complexity becomes a more powerful argument when there are several well matched parts.

It took several well-matched parts (an irreducibly complex system) to give one of cell lines in the Lenski LTEE the ability to consume citrate under oxygen-poor conditions and that irreducibly complex system EVOLVED. What’s more powerful now?

Ah. So Behe wrote a whole book claiming that there are some things that could not be explained by “Darwinian mechanisms” but which COULD be explained by other, commonly understood evolutionary mechanisms which to do not in any way entail the intervention of a Designer?

Funny, I thought his books were about something else entirely…


Are you ready to explain the origin of genetic recombination by natural means?

Are you seriously trying to claim that genetic recombination is supernatural?



Instead of committing a burden shift fallacy start thinking through everything needed for this process to originate. This is an important exercise in understanding Behe’s design argument.

Behe does not discount that the ability to evolve may be designed into organisms.

This is one possible explanation:

This latest move of the goal posts (and I’ve lost count) puts them into a spot where the sun don’t shine.