Thinking About Evolution
Both scientists and pseudo-scientists feel the need to provide evolutionary "explanations" for whatever phenomenon they study. I fact, the explanations seem more elaborate for phenomena whose very existence is controversial. Memes are the poster child for this phenomenon. Sometimes, long diversions into evolutionary story telling seem like nothing more than an effort to "sound scientific".
If the average person has any idea about evolution, he'd say it's about "survival of the fittest". In the back of his mind, he's assuming that evolution has produced an unbroken chain of more and more "fit" creatures, culminating in the most "fit" of all: man. Even "white" man. Even the Aryan race.
Actually, "survival of the fittest" is circular, if "fit" simply means the ability to survive and pass on one's genes. The key idea of evolution is descent with variation. There are many reasons why some varieties survive and others don't. The other issue is how some variations become distinct - unable to breed with similar animals descending from the same ancestor.
We are actually getting a better idea of why variations occur in the first place. 50 years ago, we thought it was mostly about "mutations". These days, many other causes are seen to be important, such as viral contamination of DNA and copying errors. We are also becoming aware of how genes control the form and behavior of animals (the "phenotype"). This means that some mutations are more likely than others. Mutation takes place within a "space" of possibilities.
Stephen J. Gould did a lot to put to rest quite a few common myths about evolution, yet many of his criticisms have not reached the general public or convinced the "experts" on evolution, such as Richard Dawkins. For example, evolution does not have a built-in preference for complexity. The path toward survival may be simplification and specialization rather than generalization and complexity. Survival may depend on "contingent" events and it's not, in itself, evidence of superior "fitness". The dinosaurs were wiped out by a radical environmental change. They were perfectly "fit" for the environment they evolved in. Gould is particularly noted for is idea of "punctuated equilibrium", which means that evolution proceeds in fits and spurts with organisms being unchanged for long periods of time, then suddenly changing for reasons that are often mysterious. This notion is particularly interesting in he case of humans, which have apparently developed critical capabilities (speech, symbolism, art) almost instantaneously in the archaeological record. It is simply not true that we need to "explain" these changes in terms of a long, slow development or by analogy to animals such as the chimpanzee who are separated from humans by millions of years of evolution. It is a mistake to think that any mental capability that humans have "must" be present in some small degree in a chimp.
Gould also educated us to avoid trying to "explain" everything about the form of an animal in terms of adaptive fitness. He invented the term "spandrel" to refer to a mutation that simply emerges without benefit or cost to the animal, but perhaps is put to use "down the line". This agrees well with what a scientist friend of mine once said about insects: "They seem to just add any old thing they can get away with".
It's also true that mutations can hand us modifications that are dominant but work against survival. As Dawkins pointed out, survival of genes is not the same thing as survival of organism. One possible example of this may be the big brains we are so proud of. They must be the result of some kind of mutation, but the mutation doesn't "care" about whether it helps us or not. That's decided by history and (according to Gould) contingent events, such as nuclear war or runaway global warming. This can be seen as a"reductio ad absurdum" rebuttal of what is almost always assumed in "pop" evolutionary arguments: that evolutionary changes must benefit adaptive fitness. This argument is especially tenuous when the organism in question radically changes the environment where its "fitness" was originally tested.
For me, all this tends to make my "bullshit detector" go off whenever I see evolution being used to "explain" the author's pet theory. It seems that such arguments are rarely convincing. Questions in he form of "why do we have this?" are usually rhetorical introductions to pure fantasy.
If the average person has any idea about evolution, he'd say it's about "survival of the fittest". In the back of his mind, he's assuming that evolution has produced an unbroken chain of more and more "fit" creatures, culminating in the most "fit" of all: man. Even "white" man. Even the Aryan race.
Actually, "survival of the fittest" is circular, if "fit" simply means the ability to survive and pass on one's genes. The key idea of evolution is descent with variation. There are many reasons why some varieties survive and others don't. The other issue is how some variations become distinct - unable to breed with similar animals descending from the same ancestor.
We are actually getting a better idea of why variations occur in the first place. 50 years ago, we thought it was mostly about "mutations". These days, many other causes are seen to be important, such as viral contamination of DNA and copying errors. We are also becoming aware of how genes control the form and behavior of animals (the "phenotype"). This means that some mutations are more likely than others. Mutation takes place within a "space" of possibilities.
Stephen J. Gould did a lot to put to rest quite a few common myths about evolution, yet many of his criticisms have not reached the general public or convinced the "experts" on evolution, such as Richard Dawkins. For example, evolution does not have a built-in preference for complexity. The path toward survival may be simplification and specialization rather than generalization and complexity. Survival may depend on "contingent" events and it's not, in itself, evidence of superior "fitness". The dinosaurs were wiped out by a radical environmental change. They were perfectly "fit" for the environment they evolved in. Gould is particularly noted for is idea of "punctuated equilibrium", which means that evolution proceeds in fits and spurts with organisms being unchanged for long periods of time, then suddenly changing for reasons that are often mysterious. This notion is particularly interesting in he case of humans, which have apparently developed critical capabilities (speech, symbolism, art) almost instantaneously in the archaeological record. It is simply not true that we need to "explain" these changes in terms of a long, slow development or by analogy to animals such as the chimpanzee who are separated from humans by millions of years of evolution. It is a mistake to think that any mental capability that humans have "must" be present in some small degree in a chimp.
Gould also educated us to avoid trying to "explain" everything about the form of an animal in terms of adaptive fitness. He invented the term "spandrel" to refer to a mutation that simply emerges without benefit or cost to the animal, but perhaps is put to use "down the line". This agrees well with what a scientist friend of mine once said about insects: "They seem to just add any old thing they can get away with".
It's also true that mutations can hand us modifications that are dominant but work against survival. As Dawkins pointed out, survival of genes is not the same thing as survival of organism. One possible example of this may be the big brains we are so proud of. They must be the result of some kind of mutation, but the mutation doesn't "care" about whether it helps us or not. That's decided by history and (according to Gould) contingent events, such as nuclear war or runaway global warming. This can be seen as a"reductio ad absurdum" rebuttal of what is almost always assumed in "pop" evolutionary arguments: that evolutionary changes must benefit adaptive fitness. This argument is especially tenuous when the organism in question radically changes the environment where its "fitness" was originally tested.
For me, all this tends to make my "bullshit detector" go off whenever I see evolution being used to "explain" the author's pet theory. It seems that such arguments are rarely convincing. Questions in he form of "why do we have this?" are usually rhetorical introductions to pure fantasy.
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