Barry Arrington should stick to what he’s good at — banning blasphemers.
Instead, he has disinterred the corpse of the “natural selection is a tautology” argument, propped it up in a chair, and is now attempting to engage it in conversation.
Trust me, Barry – that corpse is dead, dead, dead. Among the coroner’s findings:
1. Even the dimmest of IDers and creationists accepts that “microevolution” occurs. Insects become pesticide-resistant. Finch beaks change in response to drought conditions. Microbes acquire antibiotic resistance. How does this happen? Through natural selection. It ain’t a tautology.
2. The tautology mongers miss a basic point about fitness. Fitness is <i>not</i> defined in terms of the reproductive success of an individual. An unfit individual who gets lucky and reproduces successfully does not get reclassified as fit. A fit individual who gets hit by a meteorite isn’t reclassified as unfit. To claim that “the fittest” are “those who survive”, as the tautology mongers claim, is ridiculous.
Back to hunting down blasphemers, Barry. Leave the science to those who understand it.
“Suitable for a specified purpose.” – Merriam Webster
Maybe this will help, Murray sideshow notwithstanding: http://www.antievolution.org/cgi-bin/ikonboard/ikonboard.cgi?s=543d40485f2721b1;act=ST;f=14;t=7297;st=0
Nope. “Fitness” is just a convenient term for how well a particular genotype or phenotype survives and procreates. All quite correct.
And here your response seems to be simply insane. WTF does fitness have to with righteousness? Fitness is of interest because it provides information about what is going on biologically and medically. If an allele affects fitness, then it’s having a biological effect; if it’s in humans, there’s a good chance it’s having an effect on health. Those are things I study, because that’s my job.
Now, try it once more from the top: why don’t fitness and natural selection have anything to do with how I conduct my scientific work?
phoodoo, have you figured out yet whether pfcrt mutations make P. falciparum survive and reproduce better in the presence of chloroquine?
A theistic evolutionist is a creationist’s worst nightmare.
William once gleefully scampered off to UD with his own, betterer alternative to science / naturalism / materialism. Even they were unimpressed.
You provided the answer to the first part yourself:
Then you agree that “survival of the fittest” is tautological – one is just another term for the other. The concept of “fitness”, then, adds nothing to the science that isn’t already covered by comparing survival & procreative differentials. In fact, saying “survival of the fittest” harms the debate by implying that “fitness” is a commodity other than “survival and procreation”.
As far as “natural selection”, please first give me a definition of “natural” and explain why that modifier is utilized?
I didn’t say anything about survival of the fittest. I said I used the concept of fitness, and that “fitness” is just another word for “some genotypes survive and reproduce better”. To spell it out, that means I’m using the concept that some genotypes survive and reproduce better than others. Why is that not a useful concept?
Why on earth would either of those matter? “Natural selection” is term with a specific meaning. What the term’s etymology is has nothing to do with how I use the concept it names.
I’d be curious to see how others respond.
As I see it, Darwin’s insight was that ecological factors (including interspecific and intraspecific competition) play a role analogous to the role that the intentions of animal breeders plays in giving a retrospectively identifable direction to morphological variation over generations.
The formation of new scientific concepts through analogy is quite common in the history of science — compare, for example, Bohr’s model of the hydrogen atom as analogous to the solar system.
OMagain:
Robin:
That’s not selection. It’s… it’s… Divine Separation!
Um, crack a book perhaps? Or does everything have to be spoonfed to you?
No…that’s His curds and whey…
The definition for “natural” there is “not artificial,” basically, not done by humans.
The reason that modifier is utilized is that it is not done by humans.
Clearly, if you cared to know about evolution you would have already known this.
Glen Davidson
WJM:
It’s amazing that I have to keep doing this, but here goes:
The concept of “GPA”, then, adds nothing to college admissions decisions that isn’t already covered by examining grade differentials. In fact, talk of “GPAs” harms the debate by implying that “GPA” is a commodity other than “average grade”.
The concept of “batting average”, then, adds nothing to baseball that isn’t already covered by examining differences in batting success. In fact, talk of “batting averages” harms the debate by implying that “batting average” is a commodity other than “hits per at-bat”.
The concept of “drug effectiveness”, then, adds nothing to medical research that isn’t already covered by examining differences in the results of drug treatments. In fact, talk of “drug effectiveness” harms the debate by implying that “drug effectiveness” is a commodity other than “success at treating an illness”.
Isn’t “fitness” always relative to a given environment? Someone who has a QB rating of 132 would certainly be considered “fit” for American football and would likely “survive” for sometime in the sport given such fitness), but would likely not mean much for…say…banking. If so, then “survival of the fittest” cannot be a tautology.
We can make it complicated and difficult, seems to be your point. It’s what creationists do.
As a generality, it suggests that there are specifics for those who care to understand. Generalities are used for convenience and conceptualization, something that is grasped by those of us who do understand.
Glen Davidson
wjm:
Because I enter arguments for one set of reasons (such as, to discern likely true statements) and I hold beliefs for a different reasons (such as: to live an enjoyable life as a good person via a set of necessary premises).
If there are necessary premises then your personal beliefs do depend on logic and evidence that may or may not be true.
Finding true statements about the universe and accepting necessary beliefs in order to achieve a certain kind of life can be two entirely different things.
The problem is when those two things contradict each other, do you choose truth or pleasure?
wjm:
No argument or evidence can penetrate the denial upon which materialist worldview rests.
Maybe not,unlike your claim some people depend on logic and evidence to construct a view of the world
velikovskys said:
The necessary premises stem from what I have chosen to believe – IOW, I wish to believe in a meaningful good. In order for there to be a meaningful good, there are certain premises which are logically necessary. However, I could choose to not believe that a meaningful “good” exists.
Truth and pleasure do not concern me as much as being good.
Robin said:
A QB rating of 132 is a characteristic. “Fitness” is a post-hoc result. The QB with a rating of 132 may be fit … unless his off-field character issues land him in jail .. then he is not fit … unless he has friends in high places that get him off .. then he is fit …. until his penchant for running the ball blows out his knee and ends his career. Unfit.
Whether or not the characteristics of a QB resulted in comparable fitness cannot be determined until after the experiment is run in a test group.
What is the specific meaning of natural selection?
William J. Murray,
It’s the name* for a process that can be described simply as differential survival of alleles. It’s a bit like “Intelligent Design” where the name describes…well, the analogy breaks down there.
ETA *Most generally-used
That’s backwards. A QB rating is nothing but a summary of a QB’s prior performance in one or more games. It is therefore an estimator of the QB’s underlying ability. Fitness, on the other hand, is the underlying tendency to survive and reproduce well or poorly, which can be estimated by observing the survival and reproduction of a sample of that organism.
Right — and in both cases (the QB rating and the fitness) we have a statistical measurement of the underlying causal histories that generate those values, which is why they are useful in making predictions that can be tested against future outcomes.
Yeah. That”s the important point.
Yep.
Not according to biology. To wit:”An individual’s fitness is manifested through its phenotype. The phenotype is affected by the developmental environment as well as by genes, and the fitness of a given phenotype can be different in different environments. The fitnesses of different individuals with the same genotype are therefore not necessarily equal. However, since the fitness of the genotype is an averaged quantity, it will reflect the reproductive outcomes of all individuals with that genotype in a given environment or set of environments.”
But then you’ve offered two specific different environments for the same phenotype – as shown above. So fitness is not irrelevant; it is simply relative to a given environmental condition. And, as fitness is a composite of a variety of many characteristics, environment becomes even more important. So your example fails as a criticism of fitness; it actually demonstrates precisely why it is a useful measure.
Except that you’ve just demonstrated that isn’t true and that in fact fitness is quite environment specific and can be used to predict survivability in a variety of environmental scenarios.
As I am using it, it’s a tendency for an allele to increase or decrease in frequency as a result of a non-neutral fitness (as defined previously). Put another way, it’s the bias contributed by fitness to the expected future allele frequency.
So a performance rating is a tautology because it rates performance? Is that your point, William?
It is somewhat ironic that, thanks to Dawkins, the term “Darwinism” has become almost synonymous with gene-centric accounts of evolution.
The irony is that Darwin didn’t know anything about genes, and his own account of evolution is organism-centered. Darwin’s big idea was to think of species as populations of organisms — and thus the different organisms are not merely instantiating or exemplifying an essence or kind — but the organisms still take center-stage in his descriptions and explanations.
That’s why it’s consistent to be a Darwinist about what a species is while respecting Aristotelian insights about what an organism is (albeit without the essentialism). Hans Jonas (The Phenomenon of Life), Francisco Varela (Autopoiesis and Cognition), and Evan Thompson (Mind in Life) have worked this out pretty well, though there’s still more work to be done.
It’s only a vast conspiracy of sports analysts that have prevented the truth from coming out!
@ Robin
I edited out an extra “blockquote” in your 8.08 pm comment. Hope that was OK.
It’s true The Selfish Gene (I see Dawkins now somewhat regrets the title and wonders if The Immortal Gene would have been a better choice) seemed to trigger a rethink in biology to regarding the gene as the important element in selection.
Would it be accurate to say that fitness is the underlying quality, and that we measure it by assessing how successful an organism is at reproducing? If so, does that mean that when an organism is smashed by a meteor before it can breed, the impact interferes with the measurement but not the quality?
(Please excuse me if the question is ignorant–this is mostly new to me.)
This seems interesting and relevant (though not terribly surprising): Study demonstrates evolutionary ‘fitness’ not the most important determinant of success.
Pro Hac Vice,
Extinction is a common fate for species. Evolution is not fast enough to cope with meteors. 😉
One of our members, Zachriel is fond of a metaphor.
A bear jumps out of a bush and starts chasing two hikers. They both start running for their lives, but then one of them stops to put on his running shoes.
His friends says, “What are you doing? You can’t outrun a bear!”
His friend replies, “I don’t have to outrun the bear; I only have to outrun you!”
Fitness is comparative and contextual.
What is measured is RELATIVE reproductive success between subpopulations with distinct characters. It is the division into groups with distinct heritable traits that makes the observations have a bearing on fitness. Not fitness as a tautological synonym for reproductive success but as a potenital underlying causal factor. These two subgroups reproduced differentially but before any reproduction took place at all the difference between them was THAT prior feature which is NOT reproductive success. What about that don’t you get?
This is the way we test drugs for efficacy. GIve the drug to group A and placebos to group B of clinically equivalent status and measure the relative proportions of favorable outcomes. If it sufficiently succeeds relative to expected sampling noise then the drug is deemed to be efficacious. If you have a problem with tautological character of drug testing via the standardl double blind protocols then put it on the table.
Here’s a news flash for you. You cannot test “causation” directly. Its presence and strength must be estimated from effects. The (possibly) causal factors can be observed but causation itself cannot. This is just as true in aerodynamics, medicine or atomic physics as it is in evolutionary biology.
I find it frankly ludicrous that an ID proponent cannot grasp this. The “intelligfent designer” is posited as a cause of “complex specified information” or whatever it is that floats your boat, but it is never argued that even its presence is independently detectable apart from its “effect”. ID cannot even do a comparison test by fipping the “intelligent designer “switch on or off, yet you sneer at the “circualrity” of population genetics as a means of getting a handle on factors affecting fitness.
Pro Hac Vice,
It’s best not to think of fitness as a quality of the organism, because it depends not only on the organism but on its environment. A dolphin that’s exquisitely fit for a marine environment is hopelessly unfit for life in the Sahara. Fitness is relative to an environment (or range of environments).
Also, it isn’t so much that randomness and flukes like meteorite impacts interfere with the true expression of fitness. Random events are genuinely part of the environment and don’t need to be excluded. It’s just that they average out over time and across individuals.
On a planet where meteorite impacts were a daily occurrence, the ability to avoid being hit by a meteorite (say, by living in caves) might be an important part of fitness.
Frankly, I’m now getting a bit confused, because philosophy of biology is not My Thing.
Is “fitness” a statistical measurement of the causal history of iterated organism-environment interactions over generations, or is fitness itself a causal factor? Or neither? It seems like I (and keiths?) were using in the first sense — hence the analogy between fitness and GPA — but now maybe we should have been using it in the second sense?
I think we’d be flirting with danger if we were using “fitness” to mean both the measurement of a property and the property itself, because then we’d be arguing in a very tight little circle. (Perhaps that’s what “the tautology objection” has been pointing to all along?)
KN,
The study itself isn’t surprising, but the headline would be, if it were accurate.
As Alan points out, it’s relative fitness, not absolute fitness, that’s important. If your competitors are all crappy, you can get by being just a smidge better than crappy.
A better headline would have been “Evolutionary rarely attains optimal fitness”, which is fairly obvious.
I don’t do philosophy of any kind, but I think the answer is “neither”. Fitness is the expected value of measurements of reproductive success, not the result of an actual measurement; any measurement of success is thus an estimator of the fitness. A slightly deleterious allele can rise to high frequency and even fix in the population, for example, and that couldn’t be the case if fitness represented the actual result of those generations of reproduction.
I don’t think that makes fitness a causal factor either. In your analogy, measured reproductive success is the GPA, while fitness is something like scholastic aptitude. Scholastic aptitude isn’t a concrete property of the student or a causal factor; it’s a summary description of all of the causal factors that go into school performance. It is a description of how well copies of this student would perform if they went through a similar school system a large number of times.
As my use of “similar school system” suggests, all of this takes place in a model, a model in which lots of things have been simplified — like treating “the school system” or “the environment” as if they were thing you could specify or hold constant for a time. But it’s a very useful conceptual model.
I don’t think we do, unless we’re being sloppy. As one does — confusing a measurement of something with the thing itself. Does a scale tell you your weight?
KN,
It’s both. By analogy, you can say that the tensile strength of A36 steel is X pounds per square inch, but you can also say that its tensile strength is the reason that steel makes a good construction material. “Tensile strength” can refer both to the measured value and to the underlying property.
No, because the causation is unidirectional. Physics causes steel to be strong. The fact that steel is strong causes tensile strength measurements to yield high values.
Another way to see this is to substitute “tensile strength measurement” for “tensile strength” whenever it is being used in that sense.
Then it is clear that tensile strength measurements depend on tensile strength, but tensile strength does not depend on tensile strength measurements. Steel remains strong even if no one measures its strength. It’s an objective property.
Likewise, fitness measurements depend on fitness, but fitness does not depend on fitness measurements.
Steve Schaffner, and keiths, thank you both. That assuages my concern.
This makes me realize that I don’t think of fitness as causal if I’m considering the lower level qualities that contribute to fitness, but that I have no problem treating it as causal in many circumstances, e.g. allele frequencies increase because that allele confers greater fitness.
So put me down for “causal”.
In that sense it’s similar to “friction” in physics. Does “friction” cause a sliding object to slow down? Or is it the the particular collisions and temporary bonds of atoms?
Alan Fox said:
No. Saying that something performs at a high level because it has a high performance rating is a tautology that offers no meaningful information.
William,
The high performance causes the high performance rating. The high performance rating does not cause the high performance.
Did you see my reply to KN above?
KN:
keiths:
You’d think you’d point this out to the people at UD saying the mechanism of intelligent design is design but I don’t see you complaining about it when that’s said at UD.
Absolutely!
But what people are trying to make clear to you is the following:
The clue is in the word “measured”.
Still a tautology?