Biological Information and Intelligent Design: Meyer, Yarus, and the Direct Templating Hypothesis

Faith & Science Conversation
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Chris - it seems to be an informal description, not a scientific definition. Can we think of any other scientific concept that is defined as an “expectation”, without specifying the basis for that expectation objectively? Also, of course, “expectation” is another thoroughly teleological concept, implying that our definition maps to human foresight, rather than to an objective truth about the natural world. And that may be a useful idea, but is one arising from scientists’ intuitions rather than the world.

I’m OK with that if “science” is based on “beliefs about the world”, rather than “truths derived from the world”. I’m of the school that believes mind is fundamental to physical reality, but it appears to go beyond methodological naturalism and the restriction to efficient causes.

The definition would also need to be sharpened up regarding “number of offspring” by specifiying what it’s being compared to. Clearly you can’t define a polychaete as fitter than a panda because it has thousands of offspring rather than one at a time. And more specifically, creatures like pandas that concentrate on a few offspring presumably descended by natural selection from those which had more, in which case “fewer offspring” was a selective advantage to them in the longer term. Once again, we have a defintion that is true except when it isn’t.

Definition, n. Stating the precise nature of a thing or meaning of a word.

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What is your objection to the scientific definition of this term? Do you think natural selection doesn’t actually happen?

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Am I that bad at using English? What can’t be defined adequately evades definition because it is not a true entity, but a series of contingencies. Contingencies happen, and can even be described by generalised, subjective, terms.

And so for example in history, the superior sides win the wars, axiomatically. But “superior” means a million different things, including “lucky”, depending on the contingent circumstances, and so cannot be defined scientifically. And that’s why history is not a science etc (which is where I came in). The army with more weapons “ought” to win, but very often doesn’t - and science is about “is”, not “ought”.

It’s all to do with thinking carefully about the boundary between “lawlike” and “contingent”.

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OK, then, the fitness of a trait could be defined as the ratio of increased probability of successful reproduction in comparison to competitors for the same resources. Better?

Actually, a lot of empirical research has been conducted on which physical traits are more attractive than others. Here’s just one example. I could say that Valentino has a leg-to-body ratio of 1.0, therefore his attractiveness score is 5.4. But poor Falter’s leg-to-body ratio is an abysmal 1.3, giving him an attractiveness score of 3.4. This differential in attractiveness score could give Valentino an expectation of 30% more children than Falter.

Please bear in mind that while the Valentino/Falter scenario is fictitious, Swami et al.'s research on the effects of LBR on attractiveness is quite real.

EDIT: Grammar

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I don’t know if it’s your faculty for English that’s the issue, or the fact that you’re not well informed on the topic you’re attempting to address. I notice you didn’t answer my question. Would you mind answering the question? I also notice you didn’t answer my previous question “What is your objection to the scientific definition of this term?”. Would you mind answering that as well?

What makes you think natural selection can’t be defined adequately?

This doesn’t make any sense. When an army wins through luck it’s not called “the superior army” because it won through luck. The word “superior” is used to describe a specific advantage one army had over the other, such as tactical superiority, superiority of numbers, superiority of command. These advantages may or may not be decisive in securing a victory; superior numbers can be defeated by inferior numbers, and superiority of command or tactical superiority may not provide a sufficient advantage, or may be lost on the battlefield. The army which wins is not called “superior” because it won.

In order to discuss natural selection properly, you need to do more biology and less philosophy and hand waving.

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Hi Chris,

An interesting discussion on this area is in “Meta-analytic insights into evolutionary ecology: an introduction and synthesis”, by S Nakagawa and R Poulin, Evol Ecol, 2012. In this paper, a number of narrative reviews or ‘opinion’ articles are shown to differ from results using meta-analysis, e,g.:

“Meta-regression is usually applied once meta-analysis detects statistically significant heterogeneity (see below; for example, variation in assortative mating among different populations may be due to differences in resource availability between these populations). It is worth noting that questions posed through meta-analysis are usually higher-order ones, investigating generalities across studies, populations and/or species.”

A study “Meta-analysis of meta-analyses in plant evolutionary Ecology” Castellanos and Verdu´, Evol Ecol 2012, also shows how complicated these matters can become, and fitness and selection studies can lead to opposing (or contradictory) conclusions. This quote may indicate the ‘flavour’ of this study (although for a complete understanding people should read the papers and come to their own conclusions):

“We tested whether biotic or abiotic selective pressures are more important for plant traits, and if the strength of the response to those pressures depends on the plant trait studied by meta-analyzing published meta-analyses on plant responses. We classify meta-analyses according to the type of response variable studied (fitness and non-fitness traits) and the type of selective pressure examined (biotic or abiotic). Our database showed biases in the meta-analysis literature, for example that the majority of studies are focused on non-fitness traits, i.e. on traits that are not directly related to reproduction or survival, and furthermore, on non-fitness traits under abiotic selection pressures. The meta-meta-analysis showed that the strength of responses to selection depends on the nature of selection (stronger for biotic than for abiotic factors) but, unexpectedly, not on the type of trait under study as previously found.”

Obviously these type of studies are intended to advance biological understanding and should not be viewed as anti-theists vs theists, or any other such argument. However these type of studies have also been carried out in an attempt to show a clear correlation with natural selection, and while I understand the matter can be complicated, it is nevertheless a result that NS does not correlate in a scientifically meaningful manner. We can contrast this with the clear (sigma at 100% within exp data) correlation between temperature, volume and pressure in the equation (pv=nRT) - the comparison is, as they say, black and white :grinning:. Studies such as these however, underscore the ambiguous and at times contradictory view that may be made by assuming that biology can be understood based on the twin pillars of variation and natural selection.

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Yes Chris - that begins to put some precision into the term “fitness”, but raises again the question of how one can measure it in more than very restricted circumstances. “Probabillity”, after all, has to do with a predictable distribution in repeated instances. That goes along with Steve’s idea of the expected average results of a situation of selection.

And I suppose that in the case of, say, lactase persistence, which has arisen independently several times (though via different mutations), one could roughly compare the different populations, once one factors different confounding environmental factors.

That seems to be impossible in the fossil record generally, so that gauging the “fitness” of some palaeontological trait is still the observation of single historical events with no obvious probability distribution. So ones “working definition” in that bigger picture would, it appears, be an assumption of adaptive advantage which might, for example, mask mainly neutral evolution, or niche construction, or some other non-selective mechanism.

In other words, the definition is fine, but the application is as difficult and plastic as it is in other situations of “organised complexity” (Hayek) like economics or history. One still needs to know all the traits affecting survival in any instance, and all the environmental constraints producing the competition for resources.

Presumably a definition of natural selection would be a function derived from the numerical ratio defining fitness, perhaps along the rough lines of “the probability of the environment’s favouring the reproductive success of fit traits”. On reflection, though, that’s another tautology, so maybe you can do better than that!

BTW it’s good to see you engaging with the issues positively here - which are matters of philosophy of science and logic, not whether natural selection happens. It certainly beats being told one is “uninformed” after half a century in a life-sciences profession.

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You weren’t told you are uninformed. Please read my post.

Why presume? You can open a scientific textbook and actually learn about natural selection. You can read the scientific definition. If after “half a century in a life-sciences profession” you still don’t know the scientific definition of natural selection, then you are significantly uninformed.

In other words, they are not about science; like I said, it’s all just philosophy and hand waving. Why do you avoid the actual science?

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This is an example of a text book definition - if you cannot see why any self-respecting scientist would question this, and ask for a quantified formulation, than you really, really, need to be taught science and philosophy of science.

"The theory of natural selection is the centerpiece of The Origin of Species and of evolutionary theory. It is this theory that accounts for the adaptations of organisms, those innumerable features that so wonderfully equip them for survival and reproduction; it is this theory that accounts for the divergence of species from common ancestors and thus for the endless diversity of life. Natural selection is a simple concept, but it is perhaps the most important idea in biology. It is also one of the most important ideas in the history of human thought—“Darwin’s dangerous idea,” as the philosopher Daniel Dennett (1995) has called it—for it explains the apparent design of the living world without recourse to a supernatural, omnipotent designer."

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No that is not an example of a text book definition. It doesn’t even include a definition at all. That’s just the introduction to the chapter on natural selection. The definition doesn’t start until page 283, under the title (wait for it), “Definitions of natural selection”. Why didn’t you quote the actual definitions of natural selection which Futuyma provides?

It is important to recognize that “natural selection” is not synonymous with “evolution.”Evolution can occur by processes other than natural selection, especially genetic drift. And natural selection can occur without any evolutionary change, as when natural selection maintains the status quo by eliminating deviants from the optimal phenotype.

Many definitions of natural selection have been proposed (Endler 1986). For our purposes, we will define natural selection as any consistent difference in fitness among phenotypically different classes of biological entities. Let us explore this definition in more detail. The fitness—often called the reproductive success—of a biological entity is its average per capita rate of increase in numbers. When we speak of natural selection among genotypes or organisms, the components of fitness generally consist of (1) the probability of survival to the various reproductive ages, (2) the average number of offspring (e.g., eggs, seeds) produced via female function, and (3) the average number of offspring produced via male function. “Reproductive success” has the same components, since survival is a prerequisite for reproduction.

Variation in the number of offspring produced as a consequence of competition for mates is often referred to as sexual selection, which some authors distinguish from natural selection. We will follow the more common practice of regarding sexual selection as a kind of natural selection. Because the probability of survival and the average number of offspring enter into the definition of fitness, and because these concepts apply only to groups of events or objects, fitness is defined for a set of like entities, such as all the individuals with a particular genotype. That is, natural selection exists if there is an average (i.e., statistically consistent) difference in reproductive success.

It is not meaningful to refer to the fitness of a single individual, since its history of reproduction and survival may have been affected by chance to an unknown degree, as we will see shortly. Differences in survival and reproduction obviously exist among individual organisms, but they also exist below the organismal level, among genes, and above the organismal level, among populations and species. In other words, different kinds of biological entities may vary in fitness, resulting in different levels of selection. The most commonly discussed levels of selection are genes, individual organisms that differ in genotype or phenotype, populations within species, and species. Of these, selection among individual organisms (individual selection) and among genes (genic selection) are by far the most important.

Natural selection can exist only if different classes of entities differ in one or more features, or traits, that affect fitness. Evolutionary biologists differ on whether or not the definition of natural selection should require that these differences be inherited. We will adopt the position taken by those (e.g., Lande and Arnold 1983) who define selection among individual organisms as a consistent difference in fitness among phenotypes. Whether or not this variation in fitness alters the frequencies of genotypes in subsequent generations depends on whether and how the phenotypes are inherited—but that determines the response to selection, not the process of selection itself.

Although we adopt the phenotypic perspective, we will almost always discuss natural selection among heritable phenotypes because selection seldom has a lasting evolutionary effect unless there is inheritance. Most of our discussion will assume that inheritance of a trait is based on genes. However, many of the principles of evolution by natural selection also apply if inheritance is epigenetic (based on, for example, differences in DNA methylation; see Chapter 9) or is based on cultural transmission, especially from parents to offspring. CULTURE has been defined as “information capable of affecting individuals’ behavior that they acquire from other members of their species through teaching, imitation, and other forms of social transmission” (Richerson and Boyd 2005, p. 5).

Notice that according to our definition, natural selection exists whenever there is variation in fitness. Natural selection is not an external force or agent, and certainly not a purposeful one. It is a name for statistical differences in reproductive success among genes, organisms, or populations, and nothing more.

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Are you implying the introductory remarks are in error? I think you are making the argument for me, The central notion of evolution is NS, and yet there are many definitions of NS, and once again we are back to a nebulous notion of fitness. [quote=“Jonathan_Burke, post:131, topic:5784”]
Many definitions of natural selection have been proposed (Endler 1986). For our purposes, we will define natural selection as any consistent difference in fitness among phenotypically different classes of biological entities. Let us explore this definition in more detail
[/quote]

Let me know of central laws of any physical science where any scientist commences with X is a clearly defined law of science, but for our purpose, we will consider many definitions?

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No, I am not implying any such thing. I pointed out that you quoted something and represented it as a definition of natural selection, when in fact it was not a definition of natural selection. You avoided quoting the actual definitions of natural selection which the author wrote.

Natural selection is not a law, it is a process. So right from the start it’s clear you haven’t understood what you quoted; Futuyma never calls natural selection a law. Different definitions are valid because natural selection operates at different levels. It’s all natural selection, but ithe selection operates at different levels. I don’t think you understand this subject.

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What a relief, at last we have an authority who understands evolution and can tell us why a definition is sometimes that, and other times it is “a process”. Are you saying the phrase “many definitions” have been proposed (for NS) is a deep and mysterious statement that requires unique understanding.

If you had bothered to follow discussions on this subject you may have realised that the problem faced by NS is that it is a semantic statement that cannot be mathematically quantified, or derived from first principles, and yet it is presented as theory of evolution (and one of the greatest scientific ideas in human history) - a scientific theory, as all scientific theories, must be quantified so that it may be subjected to the rigours of scientific examination. Many bio-scientists have conceded (to varying degrees) this point - are you competent in this area? My guess is you are not.

I suggest you refrain from deciding who lacks understanding! :rage:

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Your misrepresentation and sarcasm neither contributes to this discussion nor masks your error. I am not representing myself as an authority, I am pointing out you didn’t understand your source.

No. I am explaining to you that you have misunderstood what it means.

If you had bothered to read what Futuyma meant, you would have understood why this is nonsense.

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So fast of the mark - a man with a bee in his bonnet. And yes, you display expertise in changing the subject and (obviously without sarcasm) decide who has understanding and who puts forward nonsense - but you show zero competence in science. If you had bothered to take the time to read material before you “shoot back”, you may have realised the semantic argument is not from your text book - but let us leave this weird exchange.

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I don’t need any competence in science in order to read Futuyma and understand that you are not only misrepresenting him but failing to understand what he has written.

Yes, yes I have. That’s the point here. I actually bothered to take the time to read.

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No, it’s a real Swami, Ed.

When I read abstracts like that, I always wonder what the selective pressure was for females to evolve with aesthetic preferences for certain mates. Could it be that females who prefer thin males have more offspring because males like females who like thin males, even if they’re fat themselves? Or maybe the female preferences arise by neutral evolution, and only the corresponding male body shapes by selection. Or maybe that’s an oversimplification, and we need to return to the definitions to sort out what’s what…

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I can’t help noticing that I’ve posted a lengthy and detailed explanation of natural selection which answers the questions asked here, and it is being studiously ignored while people continue to ask the same questions.