Survival Of The Fittest

Phrase often associated with Charles Darwin, was in fact coined by Herbert Spencer (, though Darwin used the phrase in later editions of The Origin of Species. Often misconstrued as being a statement of fact and not a generalization (only the fittest do survive in general - 'fittest' as in 'best fit' for an ecological niche, not 'strongest'), or worse, as a moral imperative (only the fittest should survive), with horrific consequences.

The most common mistake is much simpler. Survival of the fittest really applies to populations. So while an individual may be slightly more likely to survive in a given environment, it isn't really that important. It is important what happens to the population, and in particular to the genetic information contained there.

In terms of evolution, a habitat distributes a limited number of "tickets to reproduce" to the individuals living in it. The tickets do not automatically go to the strongest, biggest, or most aggressive. An animal increases its odds of receiving a ticket if it optimizes its relation to its niche. A growing gibbon has only so much calcium and phosphorous available for its bones, so it spreads them around, and makes all its bones equally weak. The "fittest" animal is not always the one whose abilities exceed its entire gene pool. This is tragic for the gibbon whose branch breaks, yet its the only way that all gibbons can optimize.

This subject is very appropriate to help us understand and leverage "EmergentDesign".
"Fittest" is often misunderstood to refer to the physical sense. In my opinion, SurvivalOfTheMostAdaptable? would be a more accurate rendering of Darwin's theory.

In my opinion, it wouldn't. Individuals survive if they're the fittest. ... {No, there are weaknesses that survive and continue to do so. People that inherit money can buy a fridge and eat from it, never going hunting and never tuning their muscles. They may have children, some of them fit, some of them weak - some of them smart, some of them not - and they may all survive via mundane jobs, welfare, or good jobs. It is not as simple as "the fittest survive". If this were true, then Beta would have won over VHS. The stronger and fitter solution was Beta but the weaker more convenient solution with poorer quality was VHS. Plastic CD-ROMS with scratches on them are also quite silly and weak - and they survived because they are cheap, poor, technically inferior technology that is convenient to produce. Whether or not CD's get phased out doesn't matter, because they survived their time as weaklings - and served their purpose. Soft tomatoes and peaches are also not very strong or fit - in fact they fall off trees and smash themselves into the ground. How stupid is that, to hang from a tree on a mere string sized twig? It is to our benefit - that these fruits are literally hanging there to be raped - they are weaklings and are essential. You don't see peaches and tomatoes adapting to be fitter - they would become rocks and nail themselves to a tree! Fruit and vegetables (especially soft ones) are designed for us to eat and hence they must be weaklings that we can dominate.

{Sexism apology: Females that wear high heels and dresses are not fit either - in fact they are much like beautiful fruits walking around waiting to be pulled off the tree and eaten. Next thing you know, someone will come up with some ridiculously over simplified theory such as: "the most beautful women survive, not the strongest, not the fittest, and not the smartest.}

{Also, the fit people wouldn't survive without weaklings; weaklings are essential. This is because the fit need something to dominate and eat. A tomatoe is a weakling. If a tomato or banana had its way, and if it wanted to be fit - it would turn into a hard rock so that we couldn't bite its private parts right off it.}

You're both off-track. Here's my opinion. First, you're going to need some independent definition of "fittest" or "most adaptable" for "SurvivalOfTheFittest" to provide any actual information, as opposed to just saying "SurvivalOfTheSurvivors".

Yes, that's the problem with the use of 'fittest' in this context. It is loaded with connotations of the fitness industry. Of course the only appropriate meaning of fit in this context is StatisticallySignificantSurvivalAdvantageBasedOnInheritedTraitsCompoundingAcrossGenerations? - which is plainly too long (see again SurvivalOfTheSurvivors).

{That is a tautology machine. Survival of the Survivors is like saying the number one is a member of the number one type.}

Second, let's say we do manage to conclude that some species A is much more adaptable than another species B: A can deal with changes in rainfall, plant life, and cloud cover, over wide ranges, whereas B's only real adaptability is the ability to survive below 10 degrees Celsius.

If the environment plummets to 9 degrees Celsius, and the rainfall, plant life, and cloud cover stay basically the same, A dies and B survives. So the most adaptable doesn't survive.

Repeat for whatever independent definition of "most adaptable" or "fittest" you want to provide.

The plain, hard fact of the matter is that SurvivalOfTheFittest is nowhere near as meaningful as most people seem to think, and that it's probably stated backwards: if you want a good operational idea of "fitness", look around at what's survived, but remember that sudden changes in the environment (e.g. big meteor impacts) radically change the rules of the game.

If I were English, I might be tempted to say "Tyrannousauruses for courses."

{Many social factors affect human evolution. "Survival" is not just about battling the weather, pray, attackers, and elements. "Fittest" is complex in social animals, and even in non-social animals in relation to mating strategies, which could perhaps be called a "temporary" social situation.}
SurvivalOfTheFittest is a statistical fact. The more "fit" you are to survive in a given environment, the more likely it is that you will survive. In my opinion, that's about the most objective definition of "fit" you're going to get. Please note that some beings more "fit" will, in fact, fail to survive when others less fit manage it, simply because we're talking about probabilities.

In the long run, however, the "fitter" beings will continue to reproduce, and their children will reproduce, and so forth. So the "fitter" beings will outbreed the "less fit".

Complete nonsense. If this were true then we wouldn't have so many stupid people and diseases.. it would recursively get better and better each year. Evidence shows that this is not the case, and that more and more people are becoming spoiled, unfit, lazy weaklings who walk to their refridgerator instead of walking to the park to kill a rabbit for the enjoyable fitness and muscle tuning experience.

Of course, "fit" is a subjective term for a subjective range of conditions. The environment is not static. What was "fit" yesterday may not be tomorrow, when the Asteroid hits today.

Adaptability is nothing to do with fitness. Adaptability is more an expression of how many environments you are "fit" in. Adaptable species tend to do well because they occupy more than one ecological niche, and they tend to be geographically distributed. This means that minor local problems, such as drought, fire, and flood, don't wipe out the entire species.

Adaptability does and can have to do with fitness. If I start running each week or each day, my body is more adapted and fit. This would seem to be a rather specious argument, since the "environment" of this "challenge" was completely artificial. One can construct any situation to "prove" some characteristic is an "advantage" over another, but the environment we're most commonly discussing here is nature. Mama Nature don't allow no television cameras around here.
In my opinion, SurvivalOfTheFittest is just the name of Darwin's theory, which is explained in his book. Names trade off accuracy for catchiness (if they didn't, they would end up sounding like the title of someone's PhD thesis).

Even "Continual directed adaptation of species to environments by the greater likelihood of survival of those individuals randomly better adapted for the environment" has flaws.

To be fair, Darwin never used the phrase SurvivalOfTheFittest. His theory is called EvolutionByNaturalSelection.
Not to be confused with "Survival of the FIT test" (see FitNesse).
Charles Darwin: It is not the strongest of the species that survive, nor the most intelligent, but the one most responsive to change.

The Economist Herbert Spencer: Survival of the fittest.
See: WorseIsBetter, InnovatorsDilemma, TheStructureOfScientificRevolutions, SurvivalOfTheFittestDebate, EvolutionByNaturalSelection

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