Mr. Judd;

Natural selection requires the functioning of intelligence? That would imply that God actively decides which living things live and die and reproduce. I had thought he was a bit more hands off than that. Isn't the thesis of the Intelligent Design view that God sets up the rules but doesn't interfere (much) with the actual running of things. Have you now switched over to pan-theism?

You're still confusing your levels. In this case, between the rules of the game and the running of the game. Natural selection of itself certainly does not require intelligence. It needs only a set of rules and a scarce resource. For instance in economics capitalism believes that the rules should be set up in a careful and minimalist way, but afterwards which particular companies are survive is left to the workings of the marketplace. Or genetic algorithms, where the fittest are selected without any intelligent involved at all once the simulation is set up (or are you implying that we've achieved artificial intelligence?).

AOG/Jeff/Brit and all Darwin fans:

Here is a quote from the article:

"Given that cultural differences such as those of language, religion, manners and customs certainly provide resistance to interbreeding and gene flow, I think it is entirely plausible that genetic differences between peoples of different regions, at least where superficial, externally prominent features are concerned, have evolved through sexual selection. Our species really does seem to have unusually conspicuous, even ostentatious, superficial differences between local populations, coupled with unusually low levels of overall genetic variation. This double circumstance carries, to my mind, the stamp of sexual selection.

In this, as in so much else, I suspect that Darwin was right. Sexual selection really is a good candidate for explaining a great deal about the unique evolution of our species. It may also be responsible for some unique features of our species that are shared equally by all races, for example our enormous brain. It is starting to look as though, despite initial appearances, Darwin really was right to bring together, in one volume, Selection in Relation to Sex and the Descent of Man."

Now, serious question. No need to respond with tales of the Inquisition or yuk yuks about talking snakes in Genecis. Is this science or is this simply an inductive effort to make the facts fit the theory? Or is it mere wishful thinking?

"Unique evolution of our species"?

Hmmm...I'm trying to guess what is behind your comment.

The "uniqueness" of humans...
Claiming that humans are unique is not the same as saying that they are 'specially-favoured', or 'the inevitable last stage of evolution' or 'the perfect species'.

We know humans are different to other things. But we also know that elephants are different to cockroaches are different to dandelions are different to....

But they're all 'successful' evolutionarily-speaking. The details of their evolution are different, but it's still all non-teleological natural selection.

Brit:

He didn't say humans are unique, he said our evolution was. Unless I'm missing something, he seems to be suggesting the evolution of humans needs a complementary theory called sexual selection that our "cousins" don't. Given the number of times we have heard the ninety-eight point whatever percent identity of our gene make-up with primates( which is supposed to emphasize how close we are), aren't we all of a sudden lurching in a new direction here?

But my question is actually more modest. Are you happy with his methodology for reaching his conclusions? Is this science?

AOG:

Chrysler?

Peter B:

It's philosophy.

I take "unique", in this context, to mean the exact course of human evolution, as opposed to any another species.
Human evolution is driven by largely the same forces as any other species' evolution, but has taken unique twists and turns.
Not all species "evolve" at the same time or rate, even in the same environment, with the same challenges.

The uniqueness is why people believe in it though. If humans didn't end up at the pinnacle of Creation no one would buy the theory.

Peter:

What Michael said. Presuming there was one instance of life starting, no matter how it happened, then all existing life can trace an unbroken path back to the origin. Whether you call it Darwinian evolution, or God directed evolution, every evolutionary path is equally unique.

His position regarding sexual selection makes sense far beyond humans. No one would accuse peacocks of being uniquely intelligent, but it some cause other than female preference, aka sex selection, is difficult to imagine as the cause of the male peacock's plumage.

OJ's assertion that intelligence is required to explain the change in knowledge or economies is wide of the mark. Intelligence is required to explain the existence of those entities, like water is required to explain the existence of fish. However, without Darwinian characteristics (variation, heritability, competition for resources), Intelligence alone is completely unable to explain change over time.

Compare a captalistic economy with a centrally planned one. The former exhibits Darwinian characteristics to a high degree, the latter (except for inheritance) to a much lesser degree. The human possessed intelligence is identical between the two. However, the rate and types of change are dramatically different for one compared to the other.

Perhaps you have a different explanation than survival of the fittest, Schumpeter's "Creative Destruction" by another name?

Jeff:

"No one would accuse peacocks of being uniquely intelligent, but it some cause other than female preference, aka sex selection, is difficult to imagine as the cause of the male peacock's plumage."

Can you conceive of circumstances where that hypothesis would be testable?

Michael:

But he has identified manners, language, customs and religion as factors that make our evolution unique(which causes a few chicken and egg problems I think). He suggests that, because of these, we have wider external variations in our appearances than other species and less genetic variations within the species. He is focussing in on uniquely human traits and positing a supplementary theory of evolution to explain then, is he not? Is that not much more significant than the issue of why peacocks have feathers? They don't have wide external variations or uniquely limited genetic variations, do they?

Any mineralogy textbook will give you examples of natural selection without intelligence when a molten mixture cools and various crystals compete with other crystals for the same atoms to grow.

Darwin once observed that the reason English aristocrats were so handsome, generally, was that the aristocratic men had had the pick of the girls for a long time.

That may not be scientific, but who doubts it?

Sexual selection is common in non-human mammals. Among many, the biggest bruiser gets the girl. Just like at Colorado University.

Peter:

Absolutely. Take all the ornamental feathers off half of a group of peacocks, and mix in half the male group size of peahens.

Watch.

Yet they stay crystals and men respectively--odd, eh?

Peter B:

Humans DO have the most complex evolutionary pressures, but, the evolution of humans is not outside explanation by evolutionary theory.
There need not be one theory for us and another for everyone else. We're not THAT unique.

Contrary to some opinion, evolution doesn't stop, merely because we can describe and affect it.
Except, of course, for all the millions of species that humans have/will cause to become extict. ( Sorry 'bout that ).

Michael:

There is a separate theory though. Or do you think Jeff & Harry will say their genes chose mates based on fitness?

Peter:

Jeff thinks the choice between a Dodge and a Chevy is genetic rather than intelligent.

OJ:
"The uniqueness is why people believe in it though. If humans didn't end up at the pinnacle of Creation no one would buy the theory."

Huh? Which theory? Natural selection doesn't put any species "at the pinnacle of Creation". It occurs to me that, like William Jennings Bryan, you've been opposing evolution because of its exploitation as Social Darwinism.

oj:

Fitness cannot be predetermined.

However, to the extent that we subconsciously attempt to choose "fit" mates, scores of studies have shown that many of the qualities that make one "attractive" are also signs of good overall health.
Also, we make many conscious decisions about potential "fitness": Social status, physical strength, job/wealth, similar backrounds, etc.
So, yes, I would expect them to say that the decision about a mate was not an exercise in dispassionate logic.

There isn't a separate theory, merely an expanded one.

Jeff:

I didn't ask whether you could prove peahens were turned on by feathers. I asked whether the proposition that Darwin's theory of sexual selection explained the evolution of the peacock was testable.

Geez, maybe we can prove evolutionary theory once and for all by asking some very pretty girls to disrobe slooowwwly with come hither looks.

Michael:

An expanded theory just for us, eh? Sounds good to me. Can I add a few things?

The proper term is inclusive fitness, and its meaning is both broader and more precise than fitness as most of you are using it.

There is no such thing as absolute fitness. If the comet lands on your head, the result will be the same no matter which genes you inherited.

And, no, Orrin they are not all still crystals. At least, not within any sensible meaning. Diamond and olivine. Trying swapping them even-steven.

It seems to me that modern humans have among the simplest evolutionary pressures rather than the most complex, in that no matter what (almost) is wrong with you (poor vision, general poor physical fitness, substandard intelligence, treatable mental illness, etc.) it is still fairly simple to find a mate and produce offspring.

Once a species has reached a certain intelligence (only achieved by homo sapiens) it would seem they are fundamentally different in that they are essentially non-extinctable. The events that caused the dinosaurs to become extinct would be catastrophic for modern civilization but would not wipe out humanity (an unprovable assertion, and let's hope it's not tested anytime soon). The ultimate fitness of a species in the long term must be its adaptability, and increased intelligence leads to increased adaptability. And since we're not going to allow some other species to become so intelligent to do to us what we have done to the mammoth, passenger pigeon, etc., the race to the top is over. We win.

You have what Princeton students used to call a cept, brian. That's half a concept.

Fitness does not begin when mates are selected. If you die at age one from malaria or dirty water, your fitness is zero.

There are plenty of places in the world where selection is very severe on humans, a third or a half or better failing even to reach the age of breeding. Most of tropical Africa, for example.

In the modern parts, selection is not so fierce, with virtually all babies at least reaching breeding age.

Once there, some become nuns and their fitness, previously high, drops to zero. Others also choose not to breed. A smaller number turn out to be diseased or otherwise infertile, and their fitness drops to zero or close to it.

Among the remainder, virtually all can and do mate. It is rarely the case in 2004 that a human cannot breed for lack of a nesting hole or food.

Humans certainly failed to breed for those reasons many times in the past, and as recently as 2003 in East Africa.

But the species is so large that genetic drift is swamped, and the gene flow is so vigorous that isolated, small populations do not exist. So speciation is not going on right now.

Even if 1918 flu sweeps the world again, speciation is unlikely because there will be more or less unaffected populations, and they will have sex with the survivors of the flu zone and the population will return to the mean.

Mr. Woods:

Ever seen a biology classroom where the apes don't ascend to homo sapien?

One notes with amusement that Harry, who gets his panties in a knot when others mischaracterize Darwinism, here treats the choice of celibacy as a function of natural selection. If Darwinism really is just a collection of such intelligent choices then who will argue with it.

I am neither willing nor able to attempt to argue about specific definitions of terms such as "fitness." I see that we agree that "speciation is unlikely because there will be more or less unaffected populations" which was my main point, because the intelligence of humanity allows us to live anywhere on the planet so that no localized catastrophe, whether it be disease, flood, glaciation, etc., can kill us all. Nor can a world-wide cataclysm, unless it were to make the entire planet unable to sustain life, because we would find any habitable region and go there.

Orrin,

Your farce is, at least, entertaining. Methinks you're sometimes a gifted "pretzel man."

Larry

Apparently the pre-human 2.4 billion years of evolution count for nought.

Jeff:

Actually it appears more and more that they are the only years that do count.

Larry:

Shhhhhhh!!!!!

Harry:

I smell a Nobel prize--Eagarism, the evolution of inorganic materials.

"Your farce is, at least, entertaining. Methinks you're sometimes a gifted "pretzel man." "

Larry, at least a pretzel maintains continuity within it's knotted, twisted structure.

Curiously enough, mineralogists do refer to the products of cooling a melt as "species" and the competition as "segregation."

But their meanings are not the same as when biologists use them.

I would call choosing celibacy an example of artificial selection, like what dog breeders do, although dog breeders don't seem to be so crazy.

Harry:

Yes, artificial selection is intelligent design.