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Thursday 24 April 2014

Survival of the fittest

http://en.wikipedia.org/wiki/Survival_of_the_fittest

"Survival of the fittest" is a phrase that originated in evolutionary theory as an alternative (but less accurate) way of describing the mechanism of natural selection. It is more commonly used today in other contexts, to refer to a supposed greater probability that "fit" as opposed to "unfit" individuals will survive some test.

Interpreted as denoting a mechanism

The phrase "survival of the fittest" is not generally used by modern biologists as the term does not accurately describe the mechanism of natural selection as biologists conceive it. Natural selection is differential reproduction (not just survival) and the object of scientific study is usually differential reproduction resulting from traits that have a genetic basis under the circumstances in which the organism finds itself, which is called fitness, but in a technical sense which is quite different from the common meaning of the word.

Interpreted as expressing a biological theory


A better way is to state it as survival of the most fitted. ie the members of a species most fitted to the environment in which they live, have the better chance of reproduction and passing on their own genes.

Interpreted as a theory of species survival, the theory that the fittest species survive is undermined by evidence that while direct competition is observed between individuals, populations and species, there is little evidence that competition has been the driving force in the evolution of large groups. For example, between amphibians, reptiles and mammals; rather these animals have evolved by expanding into empty ecological niches.[8] In the punctuated equilibrium model of environmental and biological change, the factor determining survival is often not superiority over another in competition but ability to survive dramatic changes in environmental conditions, such as after a meteor impact energetic enough to greatly change the environment globally. The main land dwelling animals to survive theK-Pg impact 66 million years ago had the ability to live in underground tunnels, for example.

Anarchists

Russian anarchist Peter Kropotkin viewed the concept of "survival of the fittest" as supporting co-operation rather than competition. In his book Mutual Aid: A Factor of Evolution he set out his analysis leading to the conclusion that the fittest was not necessarily the best at competing individually, but often the community made up of those best at working together. He concluded that
In the animal world we have seen that the vast majority of species live in societies, and that they find in association the best arms for the struggle for life: understood, of course, in its wide Darwinian sense — not as a struggle for the sheer means of existence, but as a struggle against all natural conditions unfavourable to the species. The animal species, in which individual struggle has been reduced to its narrowest limits, and the practice of mutual aid has attained the greatest development, are invariably the most numerous, the most prosperous, and the most open to further progress.
Applying this concept to human society, Kropotkin presented mutual aid as one of the dominant factors of evolution, the other being self-assertion, and concluded that
In the practice of mutual aid, which we can retrace to the earliest beginnings of evolution, we thus find the positive and undoubted origin of our ethical conceptions; and we can affirm that in the ethical progress of man, mutual support not mutual struggle – has had the leading part. In its wide extension, even at the present time, we also see the best guarantee of a still loftier evolution of our race.


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