Intelligent Design and Common Descent

EBG is an evolved beta-galactosidase enzyme.

@John_Harshman : You write: “Which facts do you wish I knew?”

When I wrote that sentence, I was thinking that I meant this in more
than just one way.

Which facts? Firstly, ANY facts: You lectured me on the fact that
Agriculture didn’t start in just one city. I thought that was so
strange. The articles and maps I produced certainly agree with you.
But because you are ignorant of my perspective, you thought you were
telling me something important.

Since I was talking about the general range of where agriculture
started in the Bible’s geographic sphere of interest, why would I care
where else in the world agriculture may have also been started?

You seem to think I am a biblicist… a bible thumper… someone who
relies on the Bible to understand the world. I am not any of these.
I am a Bible “interpreter” … not in the sense of translating Greek
or Hebrew… but in the sense of finding a way through the story
lines that would gratify YECs and OECs and their sense of values and
goals.

You seem to be ignorant of my motivations - - even though I’ve
discussed them with you before. I am not trying to convince someone
that “Geneal.Adam” had to happen. I’m endorsing and interpreting
the scenario to show a refugee from the YEC or OEC camps how it COULD
happen… and that it is flexible enough to accommodate most any
Christian denominational position there is.

Your views (which I guess are not rare on this blog), is that I
shouldn’t care about what YECs or OECs are thinking. And this, sir,
is your biggest point of ignorance. The whole point of this work for
me is to be able to GIVE something to YECs and OECs. I don’t really
give a hoot of what any of the other folks need…

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I didn’t. Of course agriculture didn’t start in cities at all; it just made cities possible, and in some cases necessary. No, my point was that it started in many regions, independently. Now, did it start only once in Asia Minor? Possibly. Did domestication of the first plants in Asia Minor spur the domestication of all other such plant species in the region, by example? Possibly. Or it might be that there are several independent sources of agriculture within the region.

If your point is that, given that the location of Eden was Asia Minor, and given that both agriculture and pastoralism are mentioned as being in operation in the vicinity of Eden during Adam’s lifetime, then Adam must not have lived before the invention of both farming and flocks in the area, then sure, your conclusion follows from your premises.

I am not very strongly concerned either with your views or your goals, only with what you say, and I don’t tend to interpret that in light of anything other than immediate context. I suggest you choose your words more carefully if you wish to make your points. I actually think that reading what you or anyone says through a lens of their presumed word views does them a disservice.

I don’t have access to the paper. Can you briefly describe the experimental methods.

They knocked out the genes responsible for lactose metabolism in E. coli and then grew this strain in media containing lactose. They later found bacteria growing in this media. These evolved bugs had a new enzyme for metabolizing lactose that evolved through two mutations in a protein that previously didn’t metabolize lactose.

Original experiment:

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@T_aquaticus
Great series of experiments. A classic.

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@Chris_Falter

Lenski’s lab has done some great work. What have they have observed has mainly been gene inactivation, often in the same genes in different strains. The thing that made the experiment famous was the evolving of the ability to use citrate under aerobic conditions. That took two to three mutations, roughly. Amplification of the cit operon and the dctA gene, followed by rearrangement that put a new promoter in front of the cit operon. This is a two to three step pathway, easily accomplished in a direct selection, especially when the cells were plated without any other food source. https://jb.asm.org/content/jb/early/2016/01/28/JB.00831-15.full.pdf

So yes, they showed what evolution could do. It can do anything within 2 or 3 mutational steps to the payoff. That’s quite a bit but it’s not everything.

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These types of experiments touch on a question that keeps popping up in these threads. I fleshed out some of these ideas in the thread below:

Basically, if ID is about guided mutations vs. unguided mutations, why would you think the mutations that pop up in these classic experiments are unguided mutations? In other words, is the intelligent designer no longer designing? It is interesting that even ID supporters like yourself seem to assume that any mutations happening in real time in these experiments are unguided mutations. There is always the possibility that I am completely misunderstanding your position, but that is the impression I am left with.

Anyway, thanks again for your gracious posts and interaction with this community. It is much appreciated.

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@T_aquaticus
Thanks for your comments. You ask insightful questions. I suppose the ID proponents you are thinking of are trained as scientists. The only way to do experiments is to expect regular, non-guided processes. Almost by definition, some process that is guided falls outside of expectations. We don’t expected to see guidance in our experiments because a) it’s very rare and b) it’s not required. Guidance, when it happens, may be so rare as to be below the level of our detection. All we have is the historical signal.

When we do our measurements, we are measuring the normal unguided processes. We can measure their rates at the present time, and compare them to historical rates. Doug Axe, myself, Mike Behe, Kirk Dursten–we are measuring the rarity of events under natural conditions. That allows us to conclude if we see things happening that should be significantly less rare, guidance is a possibility. So then, orphan genes, or I should say, de novo genes–if it proves very difficult to get de novo function by experiment (protein function in the sense I have been discussing) then we are justified in saying they may be de novo creations. Unless another more likely explanation is found.

This is my take on it.

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As a scientist I can’t help but ask how you know that guided mutations are rare, and how you discriminate against expected rare events and guided events. Just treat these as rhetorical questions for now and perhaps they can be revisited some other time. I would suspect that these are the big questions that you are trying to tackle and I hope to see your work in the future.

If we can reconstruct the ancestral sequence and therefore know what the mutations are that led to the functional transcript or protein, how do you go about determining if these mutations were guided or unguided? We know that the unguided mutations you see in the lab are capable of all the types of changes seen in these sequences (i.e. indels, substitutions, recombination), so what makes them unexpected?

As you say, it may be a matter of figuring out how many potentially functional sequences there are in random sequence, or at least in intergenic sequence that may have ultimately come from processed functional sequence. Before orphan genes are said to be a problem for evolution, shouldn’t we know this first?

I suspect that orphan genes first started popping up in ID circles because it was thought they emerged from nothing. There seemed to be some confusion between the terms gene and orthologous DNA. Two species may not share the same gene, but they can share orthologous DNA that the gene is transcribed from. Once that misunderstanding is cleared up I suspect that many of the ID arguments made by others in the ID community fall a little flat. However, your questions about the availability of function in DNA sequence space is an important and valid one.

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This is what has always baffled me about “ID theory” (aside from the fact that there is no “full-fledged theory of biological design”, as Paul Nelson has worded the problem.) How does one distinguish between guided and unguided? Until someone invents a “Intelligent Guidance Detector” or successful methodology, how can this be science instead of just philosophical speculation? To me as a non-biologist, all of this sounds like another example of “the intelligent designer of the gaps” fallacy.

No doubt my understanding is incomplete—so I’d be thrilled to get educated on this and any misunderstandings corrected.

[Meanwhile, I will reiterate for newcomers to this forum that I am a born-again Christ-follower who firmly believes that God has intelligently designed everything we observe, although as a Molinist that no doubt entails very different perspectives which many of my brethren would find uncomfortable. In any case, I’m fine with ID as philosophy and theology. I’d be thrilled to see exciting new discoveries which established “intelligent design detection” as science—but I’ve been waiting for a long time and am not so optimistic. Even so, I’m open to the evidence. I’m willing to learn and change my mind.]

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@Agauger, what do you think? (Assuming you have had time to wade through my essay.)

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@Agauger, excellent clarity!

@swamidass,

This a pretty solid paragraph by @Agauger, wouldnt you agree?

Is there a “Best-Of” folder where you can save good narrative as you go along?

Typo: ‘solf’ has been replaced with ‘SOLID

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15 posts were split to a new topic: Science and Guidance in Evolution

Does it make sense to think that de novo genes should be more common in the past? Consider a time when these genes did not exist, the potential survival advantage may have been greater than it is today.

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That does make sense. In addition to your consideration, we should consider that any new function that confers a selective advantage doesn’t have to work well at all. That’s why the size of any functional “islands” in sequence space is important to understand, as they would be landing sites for the unoptimized new functions of new genes.

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@Dan_Eastwood one of the challenges of studying de novo genes is ascertainment bias. For purely technical reasons it is very difficult to pick out de novo protein when they arise. We can’t use homology to help us detect them, and have to rely on difficult and unscalable direct detection methods instead.

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If the function is truely new, there is no competition. Any level of function provides (potentially) a new niche to explore. In a mathematical sense, a new function opens up a new way to explore functional space, and other functions which were once “distant” (mutational distance?) may now be easier to reach.

I was trying to think about this from the mathematical side, and wondering what is means to have “no function”. If a sequence really doesn’t nothing at all, there is still a biological cost to having it, giving it a disadvantageous function (energy cost with no benefit).
Aside from that, even filling empty space might be a function if it changes the timing of some other reaction. It’s not obvious to me that any protein could really be neutral to all function - it’s just a matter of what function it might accomplish.

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Not if a greater cost is required to eliminate it. Evolution is very inefficient that way.

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Interesting - In my noodling around with genetic algorithms I’ve noticed that rules for how the population is culled can affect how the optimization advances. Keep extra information in the population isn’t necessarily a bad thing.
I need to work that into the Complexity Analysis topic (an ongoing project).

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