Printable View
As I recall, Darwin talks about adaptability as the key to survival. Yet, everyone says he says survival of the fittest. These are two very different things. Adaptability, to me, means the ability to make do with what one has at hand and flourish. Survival of the fittest, to me, means those with the biggest guns win. I think Darwin said the former and not the latter. Giraffes and long necks come to mind. Input appreciated. and thanks.
2 quotes by Darwin from a quick google: -
“The expression often used by Mr. Herbert Spencer of the Survival of the Fittest is more accurate, and is sometimes equally convenient.”
“It is not the strongest of the species that survives,nor the most intelligent that survives. It is the one that is the most adaptable to change.”
There are acutally two great evolutionist: One is Darwin, the other one Lamarck (a Frenchman)
Lamarck (the older one) developed the theory of adaptability. To Lamarck is where your giraffes belong! ;) The animals suffer from a lack of food, thus they have the WILL to reach the upper leaves of a tree. They begin to stretch their necks which begin to longen as an evolutionary process. This change of length of the neck is heritary. Lamarck thus backs the theory of ACTIVE adaptation.
Darwin on the contrary claimed that beings are passively adapted: The word 'genepool' means the entity of genes in one population (e.g. a herd of giraffes). After a certain time of reproduction, this genepools holds a number of heritary, random variations of the genes (such as a different length of the neck). When now the population is exposed to a 'catastrophe' such as a lack of food, those individuals with the best features will be 'selected' and are thus able to survive, because they due to their special variations are best endowed to survive the crisis (the ones with the longer necks can reach the upper leaves). These 'selected' ones will pass on their genes to their progeny, so that the SURVIVAL OF THE FITTEST is guaranteed.
I don't know which he says, but i know why people say survival of the fittest.Quote:
Originally Posted by pathadley
Because fitness are attributes like neck lengths and so on. A single attribute like neck length can have many different degrees(neck lengths) depending on whatever combination of dna sequence is found in their gene(s), for an attribute's degree is associated with the dna sequence that encodes it. Then, your talking about genes which essentially determine an animal's fittness for specific attributes. So, people say survival of the fittest because what you have in your genes determines your degree of fitness(adaptability) to a certain environment, essentially ability to survive and reproduce offsprings for the next generation.
Adaptability of an organism to environmental conditions is random. If the organism happens to have the right genes, for the right fitness, to adapt in the right environment. Thats all adaptability means, nothing mentioned about survival for reproduction.
The two terms work off each other. But, since surviving all comes down to what the organism has in it's genes to help it adapt better, survive better, and reproduce better than other organisms , people say survival of the fittest.
Pathadley, you have the right idea. There are several loose ends that have to be tied together.
To begin with, and very important, is that so-called Darwinian evolution is not the current view of evolution held by biologists. Darwin's viewpoints were valuable as a point of reference. But time has gone by, and these things have been so reworked and reconsidered that you might say the concept of evolution itself has evolved.
It is also crucial to distinguish, always, between the survival of the individual and the survival of the species. The usual point of view in biology is that the species survival is all-important. The individual is expendable. (Interesting asides: the male is expendable for the female; the female [actually the mother] is expendable for the young. The young is most precious, as the new life is most vital to the species survival.)
As a workpoint, you probably realize that giraffes don't stretch their necks until they evolve longer necks. I believe this point was made above. That was the earlier theory, but it has been replaced with the idea that a giraffe who is born lucky, and by chance comes into the world with a longer neck, has an advantage. If this genetic freak happens to breed true, the longer-necked giraffes will prevail. They never did "stretch" their necks.
So change occurs within species, and evolution is best considered as a species change. Viruses, mutations, good and bad luck, are among the agents of change.
Over-specialization is an example of a dangerous place to be in terms of fitness. If human beings were to build up a population of, say, 6,500,000,000, and if that population were to depend, say, on electrical energy, then that would be a very dangerous kind of specialization. If such a population, already dependent for its huge numbers on the artificiality of electricity, were to then devise such a thing as a computer, say, and to depend on the computer for everything to do with warmth, food, and shelter, then you might consider the species to be recklessly overspecialized. This would be dangerous for the species survival even if it were an intelligent species.
So, when you watch a robin singing in the evening rain, you might consider whether you or he is more fit for survival. The robin will easily make it through the rainy night, without clothing and without electricity and without—by the way—a gun. Would you?
Well, people pride themselves on their massive jet planes that carry them on tropical vacations. Of course, the warbler in your back garden goes to the same places without the jet, and without the need to burn fossil fuels all over the defenseless atmosphere. There are not a great many trees growing five miles up in the air, so there are not a great many devices to filter those aviation fuel wastes up there. Again, people don't seem to be doing it quite right.
So those are a few considerations for "fitness". The warbler's lineage is much older than the person's, and, unless people totally wreck the joint so the warbler can no longer find the right habitat for his needs, he will be here long after people. He is much the "fitter" species.
One thing more. Imagine you have a lot of popsicle sticks, and you have a great big circle, say, the size of a hula-hoop. If you lay the popsicle sticks down end to end around the hula-hoop, they pretty well follow the circle circumference, right?—even though each and every popsicle stick is straight, and the hula hoop is round. Well, that is how individual lifespans are in the changing prospects of time. Each lifetime can only bend a little bit—hardly at all; we're all pretty straight, actually—but, by having kids (next popsicle stick in line), we follow around the circle, because our kids will be fairly different from us. Again, that illustrates the species changing, as opposed to the individual. "Evolution", of course, is just a fancier word for "change".
So we change as species, not as individuals.
I mentioned viruses. If this interests you at all, viruses are an absolutely amazing agent of change, straight out of science fiction (well, much better). Viruses kill us as individuals, and viruses are crucial to our survival as species.
Neat stuff. So you were pretty well right in the first place. Be careful in reading Darwin, though. A few years have gone by. Don't confuse Darwinian evolution for contemporary views of evolution, or you will be way out of date. Read Darwin for a historical viewpoint.
Fitness is a measure of the number of offspring. Those who are fittest, are those with the largest number of offspring, who inherit the various characteristics that contributed to staying alive long enough to reproduce. Of course characteristics that had nothing to do with better survival are passed on to the offspring. Best not to confuse the social darwinist "those who are strongest survive" with what Darwin really meant "those who have the most children are able to pass on their genotypes the most.
I am a new visitor of this forum. It is very nice site. This forum says about survival of fittest or adaptability .These is a good idea for our society.I my view more people give more attention to survival of fittest. We are very interested to win. I think these people are physically strongest. Adaptability is the ability to make anything . In my view I can say that these people are very intelligent.
================================================== ======
Bless
Wide Circles