Perry Marshall: What is Random?

Still waiting for you to answer some basic questions. Try this one first:

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Your use of the term “evolutionary mutations” suggests a fundamental misunderstanding of the relationship between mutations and evolution. I’ve never heard anyone use the adjective “evolutionary” in that way before. If there are evolutionary mutations, what is your definition of “non-evolutionary mutations,” then?

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Denis Alexander-Somewhat confusingly, the main use of the word “random” in evolutionary biology is quite different from its use within mathematics and physics as just described. In evolution, it simply refers to the fact that genetic variation occurs in an organism without the well-being or otherwise of the organism in view. The primary meaning of “random mutations” is that their occurrence is not influenced in any way by the needs of the individual organism in which they occur. That still leaves open the question as to whether mutations occur “randomly” in the genomes of organisms in the more technical mathematical sense. In other words, if we take the 3.2 billion nucleotides (genetic letters) in the sequence of the DNA in the human genome, is any single letter out of the 3.2 billion equally likely to undergo a mutation? The short answer, already briefly mentioned in the previous chapter, is “no”, and the reasons for that answer will be discussed further below where we discuss the overall roles of randomness and chance in the evolutionary process.

Alexander, Denis. Is There Purpose in Biology? The cost of existence and the God of love (p. 144). Monarch Books. Kindle Edition.

@swamidass,

Anyone else,

Your thoughts? Agree, disagree?

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I dispute this almost entirely. We use the term precisely as is used in math and physics. The wiki page on random variables works just fine as a definition of random for all of us.

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But we should note that they are not random with respect to location, direction, etc.–only with respect to fitness.

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They are not random with respect to fitness.

Perry Marshall – Young Earth Creationist.

If it walks like a YEC and quacks like a YEC, then it’s a YEC.

Honestly, @Perry_Marshall , I don’t know whether you are a YEC. But you supposedly are an engineer. And an engineer should be able to do better than that post you linked.

Are you willing to discuss that post, in detail, here at Peaceful Science?

Please do elaborate.

Are you claiming that Luria and Delbruck were wrong?

Perry,

Pointing me to that link shows me that you do indeed have major misunderstandings, but it does not explain your appending of the adjective “evolutionary” to the noun “mutations.” So what’s the point? In your view, are there non-evolutionary mutations too?

Just read here: Mutation is Biased Towards Fitness.

I think we’re just using different definitions of bias in this context. I am using the one demonstrated by Luria and Delbruck.

In the sense that you are using the term bias, aren’t mutations biased overwhelmingly towards neutrality over fitness?

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Maybe, maybe not.

The issue is that, speaking precisely, mutations are not actually “random with respect to fitness” (though a better way to say it is “independent” with respect to fitness). There is an interrelationship between mutations and fitness. There are patterns in mutations. We’ve known this since we first observed mutations. There is nothing there. Saying they are “random with respect to fitness” is as misleading as saying “common descent produces a perfect tree.” Both statements are not strictly true, even if they do have some truth in them. It is easy to demonstrate violations of both claims, and these violations have also been known for a very very long time. No surprises here, unless we are relying on the ignorance of our audience.

While I understand why scientists sometimes say “random with respect to fitness” and “common descent produces a perfect tree,” the sloppiness in these statements just contributes to confusion. I’d rather just be precise, acknowledging up front that these are the general rules, but there are exceptions. Life falls into a tree, but not a perfect tree. Mutations in some sense are largely independent of fitness, but this is not what we mean at all when we say “random,” nor are they totally independent of fitness. These reduced claims are accurate and true, and therefore much more difficult to strawman in an argument with ID or EES.

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@nwrickert and @Mercer

Could you say WHY Perry’s post is so frought with errors? @swamidass has said enough in previous threads, but caling Perry a YEC is not a refutation, in fact, it just means that apparently people use the term now to mean “I think you’re ridiculous.”

And perhaps @Perry_Marshall shouldn’t use the phrase “evolutionary mutation.” Fine. Why is his post wrong? I’m very curious what you have to say.

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@mark I agree that calling him a YEC is not helpful, nor is it even true. At the moment we are waiting for him to participate in a conversation with us. The door is wide open. He seems resolutely unwilling.

I assume that @Perry_Marshall is not a YEC. However, he is using YEC language, chosen by YECs to ridicule evolution. As an engineer, he should know better.

And then he goes on to say:

Yet light is electromagnetic noise. Sunlight is produced by apparently random nuclear events on the sun.

A world with no noise would be so rigidly deterministic, as to preclude any possibility of life as we know it.

Yes, I understand that noise can be a problem in electronic systems. Yet oscillators are important components of modern electronics. An oscillator depends on amplified feedback to sustain the oscillation, but it also depends on noise to start the oscillations.

Perry is too quick to condemn randomness, and perhaps not sufficiently aware of its importance.

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So … anyone want a statistics lecture on strong and weak convergence?

Actually, I’d need to do a bit of review first to get it right. The short version is that in settings where large numbers of random variations accumulate, the result may be far more predictable.

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How did this come up in the thread? ETA: Looking again, I see you are referring to role of noise.

Regardless, if you start with Prob(limits) versus limits(Prob) you are on a slippery slope to real analysis. Do you really want to go there?

How about instead talking about conditional independence and whether one can argue that mutations are conditionally independent of (ie “random” wrt ) fitness in the environment, conditional on the factors that Joshua notes.

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No, not really, it not my strength. My intent is that randomness does not imply chaos; we can reliably expect certain types of convergence.

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OK. This is more Neil’s territory than mine anyway. I am sure he has something to say.

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