A Quote by Stephen Jay Gould
What an odd time to be a fundamentalist about adaptation and natural selection - when each major subdiscipline of evolutionary biology has been discovering other mechanisms as adjuncts to selection's centrality.
Quote Topics
Quote Author
Related Quotes
There are good reasons why natural selection has become widely accepted as an explanation of evolutionary development. When applied to mammals and other large animals, it fits perfectly. But we cannot assume that all evolutionary steps arise from selection, particularly when looking at smaller animals.
Natural Selection is not Evolution. Yet, ever since the two words have been in common use, the theory of Natural Selection has been employed as a convenient abbreviation for the theory of Evolution by means of Natural Selection, put forward by Darwin and Wallace. This has had the unfortunate consequence that the theory of Natural Selection itself has scarcely ever, if ever, received separate consideration.
The theory of natural selection is the centerpiece of The Origin of Species and of evolutionary theory. It is this theory that accounts for the adaptations of organisms, those innumerable features that so wonderfully equip them for survival and reproduction; it is this theory that accounts for the divergence of species from common ancestors and thus for the endless diversity of life. Natural selection is a simple concept, but it is perhaps the most important idea in biology.
The essence of Darwinism lies in its claim that natural selection creates the fit. Variation is ubiquitous and random in direction. It supplies raw material only. Natural selection directs the course of evolutionary change.
The trick is: how do you talk about natural selection without implying the rigidity of law? We use it as almost an active participant, almost like a god. In fact, you could substitute the word 'god' for 'natural selection' in a lot of evolutionary writings and you'd think you were listening to a theologian.
The big picture, I think, is that common ancestry is evidentially prior to natural selection in Darwin's theory and in contemporary evolutionary biology as well.
Group selection and individual selection are just two of the selection processes that have played important roles in evolution. There also is selection within individual organisms (intragenomic conflict), and selection among multi-species communities (an idea that now is getting attention in work on the human microbiome). All four of these levels of selection find a place in multi-level selection theory.
Now let me step back from the problem and very generally discuss natural selection and what we know about it. I think it is safe to say that we know for sure that natural selection, as a process, does work. There is a mountain of experimental and observational evidence, much of it predating genetics, which shows that natural selection as a biological process works.
You can be a thorough-going Neo-Darwinian without imagination, metaphysics, poetry, conscience, or decency. For 'Natural Selection' has no moral significance: it deals with that part of evolution which has no purpose, no intelligence, and might more appropriately be called accidental selection, or better still, Unnatural Selection, since nothing is more unnatural than an accident. If it could be proved that the whole universe had been produced by such Selection, only fools and rascals could bear to live.
Natural selection is a blind and undirected consequence of the interaction between variation and the environment. Natural selection exists only in the continuous present of the natural world: it has no memory of its previous actions, no plans for the future, or underlying purpose.
Animals can adapt to problems and make inventions, but often no faster than natural selection can do its work - the world acts as its own simulator in the case of natural selection.
Since natural selection requires a function to select, an irreducibly complex biological system, if there is such a thing, would have to arise as an integrated unit for natural selection to have anything to act on.
Throughout his last half-dozen books, for example, Arthur Koestler has been conducting a campaign against his own misunderstanding of Darwinism. He hopes to find some ordering force, constraining evolution to certain directions and overriding the influence of natural selection. [...] Darwinism is not the theory of capricious change that Koestler imagines. Random variation may be the raw material of change, but natural selection builds good design by rejecting most variants while accepting and accumulating the few that improve adaptation to local environments.
Natural selection may lead to benefits for species, but these `higher' advantages can only arise as sequelae, or side consequences, of natural selection's causal mechanism: differential reproductive success of individuals.
People will say, "You're never going to convince me that something as complicated as an eye could come about by sheer chance." And the answer is that natural selection is the very opposite of sheer chance. Natural selection is a non-random process.
Darwin's principle of natural selection leads to the prediction that the proper way to analyze any evolutionary development is to see the new features as adaptive to environments. And that's a perfectly good principle. The problem is that there are many evolutionary biologists who view everything that happens in evolution as directly evolved for adaptive benefit. And that just doesn't work. Whenever you build a structure for adaptive reasons, the structure is going to exhibit properties that have nothing to do with adaptation. They're just side consequences.
Related Authors
Austin O'Malley Quotes
American
Scientist
Carl Sagan Quotes
American
Scientist
Charles Darwin Quotes
English
Scientist
David Suzuki Quotes
Canadian
Scientist
E. O. Wilson Quotes
American
Scientist
Georg C. Lichtenberg Quotes
German
Scientist
Isaac Asimov Quotes
American
Scientist
Jane Goodall Quotes
English
Scientist
Margaret Mead Quotes
American
Scientist
Nassim Nicholas Taleb Quotes
Lebanese
Scientist
Neil deGrasse Tyson Quotes
American
Scientist
Richard Dawkins Quotes
English
Scientist
Steven Pinker Quotes
Canadian
Scientist
Sylvia Earle Quotes
American
Scientist
Thomas Huxley Quotes
English
Scientist
W. Edwards Deming Quotes
American
Scientist