Let me remind you of what we mean by “falsehood.” A falsehood is not merely a statement that is factually untrue or logically flawed. Rather, it is a statement that when uttered in certain company rings true; It is a statement that sounds right to people; It is a statement that may be made frequently in reference to some body of knowledge, in this case, evolution or a related topic. But, the meaning that statement comes with is flawed. The statement is wrong in a way that requires explanation, and the explanation opens up the opportunity for new learning on the topic. So, the statement “humans evolved from apes” is a falsehood not because it is incorrect (in fact, it is correct), but because the implications and meaning the statement comes with for most people are wrong. (Humans did evolve from apes. Just not from those apes, and we still are apes!)
So, what is wrong with the statement “Natural Selection is Survival of the Fittest”?
Well, “Natural selection is..” should be followed by something that natural selection is, and this isn’t. Natural selection is a mechanism of evolution and by “evolution” we mean changes in gene frequency over generational time. So, with no reference whatsoever to genetics, this statement may be quite flawed. (I say what natural selection is at the end of this essay.)
Survival is a big word in this phrase, and is in fact a somewhat overwhelming word. “Natural selection is survival” is very misleading for two reasons. One is the word “survival” and the other is the word “is.” “… is survival” kinda implies that survival is the whole game, not just part of it. This seems to eliminate sexual selection from consideration. It is not (or, more exactly, not is….) survival, but rather, a number of things including survival. Furthermore, what we humans tend to mean by survival is longevity. Longevity is a trait that may be selected for. Longevity is a trait that may be selected against! In fact, shortevity may be what is selected for in many cases. Life history parameters, including how long an organism lives, are features that are shaped by natural selection, not the basis for selection.
Here’s what is really important here: We are a long lived species. Therefore, when we hear “survival of the fittest” we tend to combine our bias as a long lived species with the error of the Naturalistic Fallacy and come up with a certain amount of comfort with that statement. But if you were a salmon (a sentient salmon, that is) you might be more comfortable with the statement “Natural selection is death in a stinking mud hole right after mating!”
Natural selection is not survival, and natural selection is other important stuff that is not mentioned in the phrase. On top of that, the term “fittest” is strange. What the heck does that mean? Well, some people make the simple mistake that “fittest” means “buff” or “aerobically sound” or whatever. This is not, of course, what it means. But, understanding what it does mean does not help the phrase “Natural selection is survival of the fittest” get less falsehoody. In fact, it may make it worse.
The term “fitness” is used in evolutionary biology in relation to selection. A particular version of a genetic trait may have more or less fitness than an alternative version of that trait. So for instance, say there’s a gene that, in primates, codes for a protein essential for the implantation of a fertilized egg. Now, imagine a version of that gene that does not function at all. That would be a trait that has a different fitness than the ‘wild’ or ‘normal’ type. Specifically, it would have less fitness. Or, imagine that the run of the mill protein that helps with implantation works 90 percent of the time, but a new version comes along via mutation (by chance) that works 98 percent of the time. That version of the gene would potentially be selected for. It would have higher fitness.
So fitness is linked to selection. Something being selected for is something with higher fitness. So, to say “Natural Selection is survival of the fittest” where “the fittest” means “more genetic fitness” is a false tautology. It is a tautology because it says “fitness equals fitness” and it is a false tautology because natural selection does not usually mean more fit. Usually, it means elimination of the not-as-fit. Most mutations lead to broken, not fitness-enhanced, genetic variance. So, really, “Natural selection is the elimination of less-fit alleles” is way, way more correct, but still only partially correct.
Natural selection is a creative process that generates or shapes adaptations over evolutionary time. For a trait to be shaped by natural selection it must be genetic and heritable. For natural selection to affect a trait there must be genetic variation in the population in this trait. This variation must confer differential fitness. And, other things (random effects and selection working away on some other trait) must not swamp out the selection.
“Natural selection is survival of the fittest” does not fit very well as a definition. It should be selected against. Naturally.
More Falsehoods !!!
This post is one of a series on the topic of falsehoods. The following is a list of falsehoods posts in order:
- The Falsehoods
- “False Pearls before Real Swine”
- Falsehood: A baby is not the biological offspring of its adoptive mother
- Falsehoods: Has evolution stopped for humans?
- Natural Selection is Survival Of the Fittest (A Falsehood)
- Falsehood: Nature maintains balance.
- Is it a Falsehood that Humans Evolve from Apes?
- The poor and the dark skinned have more babies than the rich and the light skinned
- Acting for the survival of the species (a falsehood)
- Culture Overrides Biology (Another falsehood)
- What is the Placebo Effect, and it it getting stronger?
For more about Natural Selection, see this post.
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Genius. I parsed this without a second look, then realized others might not… I figure it’s because of my programming background. “!= something” doesn’t mean “= !something”. The former is merely a test of inequality, the latter is a statement that it equals the exact opposite of something.
I was originally going to write the entire post in perl…
This is why “theory in words” is evil.
You may have to start that way, but if in the long-term you can’t reduce it to equations and definitions relating those equations to observations, you’re screwed.
Let’s drop “natural selection is…”, and just layout the equations — which were mostly worked out by the ’30s.
Science == math + data.
For discussion about the supposed tautological character of “survival of the fittest,” you might want to take a look at John Wilkins recent series of posts at Evolving Thoughts.
There are also quite reasonable ways to interpret the phrase “survival of the fittest” that avoid the charge of “falsehood.” For example, suppose we focus on traits (rather than organisms), and interpret ‘survival’ as a shorthand for ‘representation in future generations.’ That sort of survival of the fittest comports well with our current understanding of natural selection.
Wow, Greg. I’ve been reading a few posts where you seem to object just to object recently, and this seems like one of them. “survival” goes beyond survival of the individual (although survival of the individual is pretty necessary if the individual is to reproduce and pass on those adaptive traits) and “fittest” doesn’t refer to physical strength or how often an organism shows up at Gold’s Gym, but it’s success in passing on it’s genes. I’m a non-scientist, a former English teacher, and if I can understand that, I don’t understand why others outside the scientific community can’t.
As a general definition for the lay population, so long as the terms are adequately defined, I see no problem with the definition, especially because it’s something that fits in with the schema people have already developed on the topic. It’s easier for them to understand that their definitions of the terms are wrong than to try to teach them that the term “survival of the fittest”, which has such vast popular usage, isn’t correct (when it really is) You’re not going to be able to say “Natural selection is the elimination of less-fit alleles” to 3rd graders (or those with 3rd grade mentalities) and be able to have them understand.
Bob and Dorid: You are both making good points, but missing a key one. I’m not objecting just to object. I’m exploring the use of falsehoods as a pedagogical tool.
In this context, saying “Natural selection is the survival of the fittest but … you must understand tat survival means bla bla and fittest means bla bla” is fine. I agree with that. That is, in fact, what I say.
The point here is, however, that if you walk into a classroom of college freshman in an intro bio for non-biology majors class and say “Natural Selection is survival of the fittest” then … they will experience the falsehood phenomenon, not the corrective you (and I) are suggesting.
And Dori, I think you have to look more closely at what I’ve written. I gloss the “fit = buff” part, only barely mentioning it. Don’t you thing that since the vast majority of “natural selection is elimination of “unfit” alleles that focus on survival of fit rather than elimination of unfit will lead to people not noticing, or being reminded of (to the extent that a phrase like this can be a heuristic) the most important part?
“I was originally going to write the entire post in perl…”
Don’t taunt me, you’re playing with fire!
Seriously though, this is a good post. ‘Survival of the fittest’ has this fantastic ring to it, but I think what we’re really trying to say is something like ‘generational continuation of the fit* enough.’ Once you include that * and footnote it really takes the billboard quality out of it.
There are a lot of maladaptive ideas that come out of this statement, much like initial images conjured up by telling students about light waves. This picture of ocean waves or a guitar string hangs on for a long, long time.
After Ernst Mayr’s definitions I expected a much more simplest post, from a gene-centric point of view, like:
“survival of the fittest” being simply translated as “persistence of the fittest alleles [plural, double emphasis]”.
“Random or non random persistence?” Ernst would say.
For a course I took at LSU on Macroevolution, we read and critiqued Mayr’s “This is Biology: The Science of the Living World”–it was pretty interesting. I had some issues with a few parts, but overall, it was a pretty nice introduction for most people.
I like the falsehood (as teaching tool) idea. This particular statement: Survival of the fittest, is usually stated in my experience as “Evolution is survival of the fittest”. That is even more false than the one you are dealing with here.
Mayr is good, richly historical, always challenging and clearly thought out.
Richly historical? Of course, he LIVED THROUGH THE HISTORY! The man was 100 when he published his last book. He was also very critical of the gene-centered view of evolution, and presented some rather persuasive arguments against it.
Dorid says “fittest” doesn’t refer to physical strength… but it’s success in passing on it’s genes”
It quite clearly refers to physical strength (or similar) to me. I think you’re project your existing knowledge of the subject into a word which is not accurate enough to describe the situation.
The problem with the phrase “survival of the fittest” to my mind, is that when I read it I think “No, it doesn’t matter how ‘fit’ you are, if you die before mating, you don’t pass go. Fitness is irrelevant, because it comes down to the ability to pass on your genes by surviving long enough to mate”
The phrase “Survival of the fittest” is also wrong to me when I imagine that a particular animal may all die in a localised flood and other neighboring variations, who were “inefficient” and on the verge of dying out, suddenly became more numerous.
I know that natural selection “can” work like this and “fittest” is not my description of these opportunistic slackers who just happened to be in the right place.
Or is such a process that I’ve described not “natural selection” but one of the outside forces that affect it?
In that case, what is a word that describes all these effects combined?
Maybe “persistence of the contigently fittest alleles” answers Ernst’s question. Does it?
“Nonrandom” is just too vague to support a useful definition. Sorry Ernst.
“Survival of the fittest” only works if you add so many qualifiers that the terms lose their everyday meaning – i.e., it doesn’t work.
“Differential propagation of heritable features caused by their effect on the reproductive success of their bearers” covers the vast majority of cases of interest in biology. Not perfect (you can certainly spot ambiguities), but sufficient for Evolution 101. And certainly much better than “survival of the fittest”.
I know that natural selection “can” work like this and “fittest” is not my description of these opportunistic slackers who just happened to be in the right place.
By definition, this “survival of the slacker” effect you are speaking of is not natural selection, it is genetic drift.
oldcola: persistance is the default, and does not require selection. Elimination is actually what happens. Remember, mutation arise and then are eliminated, selectivel.
“Nonrandom” is just too vague to support a useful definition. Sorry Ernst.
Sorry, toto, but this is not vague! the phenomenon itself can’t be pinned down any more specifically . Nonrandom elimination is actually perfect.
Differential propagation of heritable features caused by their effect on the reproductive success of their bearers
That only works if you are prepared to not care that “reproductive success” is only an approximation for fitness, and in fact, is often a totally sucky approximation of fitness. All of the eusocial traits but a few are thus unaccounted for by this theory. That is better than survival of the fittest, but in my view not good enough for 101. SInce this is the most important concept in most evolutionary biology courses, it’s OK to go beyond a single sentence that 80 percent of the students will quickly morph in their bran into a falsehood!
I think we may have the kind of “half-empty, half-full” disagreement here. I see elimination as the default situation.
Oldcola: I doubt we are disagreeing at all. Most mutations probobaly randomly walk off the edge all on their won (fixation, neutral). Some don’t (still, neutral). Selection escorts them to the edge and pushes them off.
If you think about it not too long, you either become Larry and simply stop believing that natural selection could do anything, or you start really appreciating hidden variation!
Natural selection is the universe’s tendency to increasing probability over time of having patterns around, where the patterns have the property of tending to increase probability of having a pattern like that around in the future.
Greg Laden: Natural selection is a creative process that generates or shapes adaptations over evolutionary time.
Quibbling, that ALSO is a lie. Mutation generates the adaptations; natural selection shapes the distribution (and sometimes, expression) of the generated adaptations.
Abb3w: I think your pattern developing thingie sounds a little teleological.
Natural selection is the survival of the FASTEST (to reproduce, run way, or get to the food!)
I doubt that fitness meant to Darwin ‘buff’/physically fit, rather, “fitted” in his terminology to the habitat.
I think there is a general confusion in the commentary here between neutral theory and selection theory. Also, the source of novelty often (usually?) but not always mutation.
“”humans evolved from apes” is a falsehood not because it is incorrect (in fact, it is correct),”
Is part of that falsehood that humans are not apes any more?
very punny
I don’t see any difference in saying “elimination of unfit alleles” and “survival of fit alleles”. Alleles are only fit or unfit in relation to other alleles. An unfit allele decreasing in frequency is the same event as a fit allele increasing in frequency.
I’m not even sure it makes sense to say that, since deleterious mutations are more common than beneficial ones, “elimination of unfit alleles” is more common than “survival/propagation of fit alleles” – because they are the same event. When a novel deleterious mutation gets negatively selected, its alternative alleles are getting positively selected.
I think it’s only confusing to talk about survival or elimination, which are really just two sides of the same coin: differential reproduction.
1) Survival can be a passive process. 2) most of the time it is elimination. The difference is somewhat semantic, though.
However, no, differential reproduction is not a good term. I should do a post on why.
article CSM 24aug09, plus comments, with mine, robert chadis.
Biologists have learned a lot about evolution since Darwin published his theory 100 years ago. But nature can still surprise them.
Sometimes itâ??s a new fundamental insight. The discovery that an ancient merger of microbes opened an unsuspected evolutionary pathway for higher organisms gives biologists a new perspective on earthly life. In announcing this on August 20, molecular biologist James Lake said that it now is clear that â??higher life would not have happened without this event.â?
Or, sometimes itâ??s a tweak to our understanding of an evolutionary detail that has consequences for our time. A new look at 200 million years of marine clam evolution reveals that some closely related clusters of species are more vulnerable to extinction than are life forms generally. Announcing this research a few weeks ago, evolutionist Gene Hunt said this shows that big extinctions â??tend to preferentially cull the more vulnerable lineages, leaving the resistant ones to proliferate afterward.â? The lesson for conservationists: if you want to preserve species diversity, seek out the vulnerable and give them extra protection.
The take away lesson for the rest of us is not to take present scientific knowledge of evolution for granted either in speculating about the development of life on Earth or in environmental planning. What we donâ??t know can trip us up.
Commenting on discovery of that microbial merger over 2.5 billion years ago, Carl Pilcher, director of NASAâ??s Astrobiology Institute, called it â??a major advance in our understanding of how a group of organisms came to be that learned to harness the Sun and then affected the greatest environmental change Earth has ever seen.â?
Those organisms were the cyanobacteria that evolved photosynthesis. Their production of oxygen changed the atmosphereâ??s chemical composition, preparing the way for evolution of more complex organisms including plants, animal, and humans.
The Astrobiology Institute is a collaboration of NASA with scientists in 14 US teams and 6 international consortia. It exists more on the Internet than at any one institution. In this case, Dr. Lake from the University of California at Los Angeles is carrying out the research. He has reported the details in the Aug. 20 online edition of Nature. The microbes that merged and evolved into cyanobacteria were a type of single-celled organisms called prokaryotes. Lake found evidence of that merger in comparing proteins from more than 3,000 different prokaryotes living today.
Dr. Hunt at the Smithsonian Institution, Kaustuv Roy at the University of California in San Diego, and David Jablonski with the University of Chicago reported the research on extinction in Science. They believe their study of a global database of bivalve fossils reveals a universal fact of evolution. As Dr. Jablonski stated it, â??Both background extinctions, which represent most extinctions in the history of life, and mass extinctions tend to be clumped into particular evolutionary lineages.â?
In other words, when it comes to extinctions, evolutionary history tends to be destiny. The evolutionary path of some related clusters of species has made them less resistant to extinction pressures than are other lineages.
Darwinâ??s principle of evolution through natural selection still guides research on earthly lifeâ??s history. But scientists must watch out for unexpected twists and turns.
( More stories )
Comments
1. robert chadis | 08.24.09
glad article focuses on correct approach in Darwinâ??the vector of his thought is not primarily survival of the fittest, but, rather, non survival of what does not fit, in the relationship of the organism with the environment. By the way, let´s save the orangutans by getting indonesia to make their habitat protected national parks. ah, yes, and how about saving the gibbonsâ?¦they are not considered great apes, as they are smaller, besides, they move around too much to play with, geeâ?¦
will the space invaders blame us?
ah well,
elf
elf.galba@gmail.com
2. Fred | 08.24.09
Mr. Chadis overstates his point. A species may be perfectly adapted to its environment but a new arrival may out-compete the original inhabitants and supplant them. From this perspective (i.e., the environment does not change), the issue is not that the original species is no longer fit, it is all about the fitter species taking over. It is a delight to learn about the continuing â??evolutionâ? of our detailed understanding of Darwinâ??s beautiful insight.
3. Dan | 08.25.09
And then, after the cyanobacteria flooded the earth with oxygen, which is a very dangerous chemical because it causes oxydation( why so many people take anti-oxydants in the hope of avoiding cancer) it led to the oxygen holocaust, in which 99$ of the worldâ??s life forms died, and so a new symbionic form appearedâ?? the nucleated cell merged with the ancestor of the mitochondrionâ?? and all oxygen-using forms of life today are the children of that merger. Youâ??ve heard of mitochondrial DNA? This is the DNA remnant of the ancient symbiont, and it is different from the nuclear DNA which holds the code to the structure of the entire organism.
These events go to show that as evolution sometimes moves by competition, at other times it moves just as importantly by cooperation.
4. Eric Klieber | 08.27.09
Itâ??s all well and good to identify vulnerable lineages in 200 million years of clam shell fossils, but how does one identify which contemporary lineages are vulnerable? Will data from clams help us?
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“Survival of the Fittest” is a horrible metaphor to use as a description of how selection operates. Selection involves more than individual survival. Richard Dawkins and Jerry Coyne both have used “non-random survival” to describe selection which is almost as bad as “survival of the fittest.” Scientists who are trying to communicate what makes selection a powerful process need to use a definition of selection that is comprehensive with respect to the causes and consequences of evolution. It is time to present students and the general public with the realistic speedy strongman version of how selection operates rather than the slow strawman version. What are the causes and consequences of evolutionary processes?
The following is my proposed scientific description of natural selection.
Charles Darwin (1859:62) used the metaphor â??Struggle for Existenceâ? to describe the ecological interactions that individual organisms have with (1) the physical conditions of their environment, (2) individuals of other species, and (3) individuals of the same species. These ecological interactions cause the natural (including sexual) selection of hereditary variations, that is, cause the selective survival of genes, the selective exponential multiplication of genes and the selective recombination of genes (via mate choice) that affect adaptations (designs) for survival and reproductive success each generation.
The adaptations we observe today are the product of natural selection operating on genetic variation produced by mutations, sampling error (genetic drift) and selective recombination (via mate choice) each generation over billions of generations.
Science educators need some kind of comprehensive description like this to help students better understand what processes cause adaptive evolution and its relationship to nonadaptive evolutionary processes. Evolution is the result of “chance and necessity” with necessity (selection) superimposed on chance every generation.
This is a proposal. There probably are better ways for science educators to briefly and accurately summarize the causes and consequences of selection that also include interations with accidents–mutations and sampling error.
willie: I think your pattern developing thingie sounds a little teleological.
Well, since “human” is one of the patterns, and (presumably) humans design some things, clearly design must be one of the potential consequences. However, in the sense used, such ephemeral dynamic “patterns” do not require design as a precursor; randomness suffices. EG: flip ten coins, and you will get some ten element binary (heads/tails) pattern. They need not even be fair coins.
In the philosophical sense of teleology, design presupposes both choice and purpose. Functionally, choice may be here defined as the function defining probable interactions with the rest of the universe for any arbitrary pattern/entity, whether a human or a water molecule. However from this vantage, “purpose” is not a mathematical prior to existence (for which it was chosen itself), but a mathematical consequence (for which it chooses). Looking at wikipedia, this would be a purely “intrinsic finality”; and furthermore only in considering “intrinsic finality” only as measured by how long something behaves consequent to its existence.
Philosophically, the math constraint comes in to solve Hume’s “Problem of Induction” (recognizing patterns within objects) and its prior, Epicurus’s “Problem of Deduction” (recognizing a pattern of experience as an object).
Greed Cancer Cells Also Follow Laws Of Evolution
Failing Treatment Of Economic Collapse Simplified
A. “Survival of the fittest: even cancer cells follow the laws of evolution”
http://www.eurekalert.org/pub_releases/2008-08/foas-sot080108.php
Of course. Expected. The cancered cells are proliferating. The energy constraint of their genome is enhanced. Their genes effect ingestion of the energy of their host cells in order to survive. They proliferate, evolve. Yes, theirs is a shorter survival time, postponement time of loss of energy, shorter than the survival time of uncancered organism’s cells. But, like and even more than most humans, they instinctively act per the encountered circumstances. This is evolution. This is natural evolution.
B. Life genetics evolves via culture. In human culture one component is unique, it bypasses genetics.
Culture is a ubiquitous biological entity
http://www.the-scientist.com/community/posts/list/98.page#266
There is natural ubiquitous evolution and there is human cultural evolution. Humans evolved language, that became a biological entity.
Whereas nature’s evolutionary rungs are gains or losses of energy constraints for few “fittest” at ongoing circumstantial constellations, including modifications of genetic expressions, some Western cultured groups assess and extend the prospective temporal limits of evolution beyond the immediate scenario. They manipulate the circumstantial constellations, postponing or modifying natural evolution, to gain enhanced energy constraints for a community much larger than of “few fittest”. This is what all levels of politics are about. Local, national and international.
C. Greed cancer cells also follow laws of evolution, with money being humans’ cultural energy.
Not only physiological cancer cells follow the laws of evolution. Human greed cancer cells follow them, too. Evolution is evolution. EOTOE.
The total amount of cosmic energy is constant even if mass diminishes with the ongoing expansion. Hence the universal melee of mass specimens to ingest each other’s energy to survive. Ingesting energy translates into ingesting mass, which is the other face of energy. Humans artificed money to stand for energy. The ideal ethical goal per the 20th-21st centuries technology culture is amassing money, the human energy artifact. Humanity’s present technology culture is founded on the brilliant idea that whereas in nature it takes work, converting of mass, to ‘amass’ energy, humans will – instead – print money, print it and base on it a make-belief culture, founded on make-belief energy. Printing money, posits the brilliant thinking, enables us to bypass nature, to spend more energy than we actually amassed.
D. So again and again, the economic collapse will not be repaired by mechanisms but by basic cultural modifications
The greed cancer cure requires a prolonged resolute determined change of culture, of values and ethics and goals, of consumption and living modes and patterns.
Dov Henis
(Comments From The 22nd Century)
03.2010 Updated Life Manifest
http://www.the-scientist.com/community/posts/list/54.page#5065
Does the comment by Dov Henis make sense to anyone?
Quote:
33
Does the comment by Dov Henis make sense to anyone?
Posted by: Jared
end quote
Yes. It does. Plain and simple.
The greed cancer evolved and persists biologically. “Human nature”. Its cure requires modification of a natural process, i.e. cultural modification. Trials of various mechanisms within the present technology culture will not cure anything. They will ONLY buy VERY LITTLE time and lead to a greater collapse…
Plain and simple, but who is prepared to indulge in a prolonged resolute determined change of culture, of values and ethics and goals, of consumption and living modes and patterns. It is much easier to play hopeful make-belief with mechanisms…
Dov Henis
Even a small cell change can generate millions of logical statements. That we deduce the extreme amount of information to a “there” but not “there” explanation denies a large library of physical processes that need to be understood.
You are looking at this argument from a strange viewpoint. This is a biological question that needs a biological answer… not semantics. The term “survival of the fittest” thoroughly explains and describes natural selection. Survival = survival of an individuals gene pool; fittest = ability of an organism to survive and contribute its genes to the next generation.
The business loans suppose to be important for people, which want to organize their organization. As a fact, this is very easy to receive a secured loan.
this paragraph i said in my competition and i won first prize. my all teachers said where did u get this??…… and many other questions were raised to me
One thing i have always wondered is , what exactly do Biologists mean when they say ‘Fit’.
As far as i know, there is no specific definition. A quality that is ‘Fit’ in one particular situation is ‘Unfit’ in another.
So the concept of fitness itself is a highly fluid one and in many cases we determine something is Fit only after the Event.
They might as well say whatever survived , survived and there is a reason for it.
Ashwin,
Fitness is the relative effect of an allele (though sometimes measured as a trait, which is somewhat indirect) on representation of itself in the next generation. That is very precise concept.
However, as you imply, the actual operationalization of this is not as clear. Defining what the genetic underpinning of a trait is is difficult. (Fitness can be used in non-genetic systems as long as it is something that replicates fairly reliably). The actual fitness of a variant often depends on the context, so the fitness can change with the context. Because of this, the actual fitness is probaby best determined after the fact, and that makes fitness look to many like a tautology. But the concept of fitness, what it actually is, and how one would measure it given enough control, is not a tautology and not ambiguous.
I’ve learned to see it as “Any heritable adaptation not leading to a disadvantage for a species’ survival within its environmental context shall successfully pass to the next generation.”
By “not leading to a disadvantage” I mean we don’t pass on the Best Adaptations, just the Good Enough Adaptations. After all, arthritis doesn’t appear to provide any advantage. But since it hasn’t stood in the way of species survival (or individual survival), then it persists. Survival: persistence of the adaptation. Fittest: Appropriate enough for the context.
Is this not accurate?
Kane, I’m sure something like that happens a lot. But, different genetic adaptations may compete with each other in the same gene pool, so “good enough” loses to “gooder enough.”
Also, the trait has to be heritable/genetic.
And then there are polymorphisms. Something we see as a disease may have a benefit somewhere else in someone’s life history.
See: http://scienceblogs.com/gregladen/2008/02/05/the-three-necessary-and-suffic-1/
> But, different genetic adaptations may compete with each other in the same gene pool, so “good enough” loses to “gooder enough.”
In my mind, that seems like it would alter the environmental context. The trait would be good enough *until* the context is changed. And wouldn’t the whole of the environment, including competing species, be the context?
> Also, the trait has to be heritable/genetic.
I did say “heritable”. 🙂
> Something we see as a disease may have a benefit somewhere else in someone’s life history.
Within the same species? If so, that’s an interesting concept I hadn’t heard of. If not, then it seems that it would be a different context.
@Kane Gruber #43: Greg wrote, “Something we see as a disease may have a benefit somewhere else in someone’s life history.” To which you replied, “Within the same species? If so, that’s an interesting concept I hadn’t heard of.”
Please look up “sickle cell trait.” It is not the only example, but it’s the canonical one used in lay discussions.
Kane, yes, the competing species is definitely part of the context!
My comment on heritability is in reference to your example.
Yes, a trait may have a negative and positive effect. That is actually quite common .
Ah! Interesting. I love discussing this stuff. The more we can understand it, the better we get.