Posted on 12/29/2004 9:14:28 AM PST by aculeus
Emergence of society may have spurred growth
The sophistication of the human brain is not simply the result of steady evolution, according to new research. Instead, humans are truly privileged animals with brains that have developed in a type of extraordinarily fast evolution that is unique to the species.
"Simply put, evolution has been working very hard to produce us humans," said Bruce Lahn, an assistant professor of human genetics at the University of Chicago and an investigator at the Howard Hughes Medical Institute.
"Our study offers the first genetic evidence that humans occupy a unique position in the tree of life."
Professor Lahn's research, published this week in the journal Cell, suggests that humans evolved their cognitive abilities not owing to a few sporadic and accidental genetic mutations - as is the usual way with traits in living things - but rather from an enormous number of mutations in a short period of time, acquired though an intense selection process favouring complex cognitive abilities.
Evolutionary biologists generally argue that humans have evolved in much the same way as all other life on Earth. Mutations in genes from one generation to the next sometimes give rise to new adaptations to a creature's environment.
Those best adapted to their environment are more likely to survive and pass on their genes to the next generation.
The evolution of a large brain in humans, then, can be seen as similar to the process that leads to longer tusks or bigger antlers. In general terms, and after scaling for body size, brains get bigger and more complex as animals get bigger.
But with humans, the relative size of the brain does not fit the trend - our brains are disproportionately big, much bigger even than the brains of other non-human primates, including our closest relatives, chimpanzees.
Prof Lahn's team examined the DNA of 214 genes involved in brain development in humans, macaques, rats and mice.
By comparing mutations that had no effect on the function of the genes with those mutations that did, they came up with a measure of the pressure of natural selection on those genes.
The scientists found that the human brain's genes had gone through an intense amount of evolution in a short amount of time - a process that far outstripped the evolution of the genes of other animals.
"We've proven that there is a big distinction," Prof Lahn said. "Human evolution is, in fact, a privileged process because it involves a large number of mutations in a large number of genes.
"To accomplish so much in so little evolutionary time - a few tens of millions of years - requires a selective process that is perhaps categorically different from the typical processes of acquiring new biological traits."
As for how all of this happened, the professor suggests that the development of human society may be the reason.
In an increasingly social environment, greater cognitive abilities probably became more of an advantage.
"As humans become more social, differences in intelligence will translate into much greater differences in fitness, because you can manipulate your social structure to your advantage," he said.
"Even devoid of the social context, as humans become more intelligent, it might create a situation where being a little smarter matters a lot.
"The making of the large human brain is not just the neurological equivalent of making a large antler. Rather, it required a level of selection that's unprecedented."
Guardian Unlimited © Guardian Newspapers Limited 2004
Because you have endorsed the notion that there is sufficient uncertainty within Genesis to permit either an old earth or a recently created earth, I presume you also endorse the notion that there is sufficient uncertainty within Genesis to permit evolution as well. If not, why not?
Sorry it took so long to respond. Your wit absolutely floored me.
I suggest you check it out if you are serious about having your questions answered. Otherwise, we may think you are just asking questions for some other purpose...
Heh,heh .... whatever.
M-PI: "Intelligent Design and Darwinianism definately ARE in conflict."
_Jim: "I suppose, if you need a bogey man to throw stones at ..."
Pick out the points the "bogey man" is making here that you disagree with, and refute them with the legitimate evidence I'm sure you must have for each of them:
http://www.deepscience.com/philosophy/design.html
That's a pretty thin thread. More realistic, but still a stretch, is something like the years between Robert E. Lee and his father, who was one of George Washington's generals. It would take a somewhat larger group than your 20, but still not all that many.
You must spank a liberal woman to make her conservative. Or at least pay attention to you:):)
I take it you either do not know the answer or are too embarrassed to give an answer.
"What's the bit about "society?"
I don't get this either. It would seem that by being in a society the dumb ones would be able to survive because of the kindness of their relatives and neighbors. Out in the jungle/savannah whatever by yourself - if your're dumb you die.
Kind of like today (the dumb ones surviving anyway).
Although in a society, all members might be more able to survive and therefore ability to reproduce more. Although I imagine prehistoric rabbitsalso had population explosions at times - but did that make them any smarter?
I don't understand your strawman. Has anyone ever suggested that cats have "turned" into dogs or seals into whales? I didn't think so. I posted, as one example, a summary of the evolution of bears and dogs from a common ancestor. Do you disagree with that evolutionary tree? If so, specifically how? Thanks for your input.
"Human brain result of 'extraordinarily fast' evolution"
Some are, some aren't.
Interesting source. Not only did it cite to Watergate-era jailbird Chuck Colson, but to 19th Century financier Jay Gould and his amazing theory of the "quantum jump." What a scientific lineup.
You never asked that question.
(WHY the charade of an over-aged earth and the mystery of matter and the atom et al.
I don't know. I do know that various interpretations of scripture allow for a much older earth than 6000 years. But since it's never been a point of concern to me I haven't looked into it more deeply.
What is the mystery of matter and the atom? Everything has to be made of something and why shouldn't an atom be a good building bliock. Seems that it's been a pretty stable material for God to make stuff out of. I don't understand what your problem with the physical properties of God's creation is
What is God trying to hide through all this eleborate 'charade'? Shouldn't/couldn't the universe have been made in a more straight-forward manner (you know the drill by now: dogs made of dog-stuff, et cetera).
What charade. God reuses code. God resuses building blocks. Once you have the ideal, elegant solution to a problem then why not use that solution in all instances of that problem.?
You: "Then I assume you can explain WHY evolution should be believed without this evidence?"
The theory of evolution does not predict the existence of "fossils of cats turning into dogs, seals & walrus turning into whales." Thus, the nonexistence of such evidence does not falsify the theory. Kinda' rudimentary.
Your insistence that the theory does to predict the existence of such fossils does not make it so. Perhaps you are unwittingly expressing heartfelt disagreement with a theory that you have fabricated out of ignorance. I, for one, don't believe that. I think you are disagreeing with a theory that you are deliberately misrepresenting, and that you are deliberately misrepresenting it to achieve some goal.
Which brings me back to the questions (which I will modify slightly to accommodate this most recent assertion of yours):
What is your goal in deliberately misstating the theory?
Do you advocate such a deliberate misstatement of the theory to students?
And how do you reconcile Biblical admonitions against dishonesty with the deliberate dissemination of falsehoods to unsuspecting students?
This is exactly correct and I never claimed otherwise
Actually that was answering the question and spunkets has every right to answer any question asked on this forum. Just as we all do. That's what makes this such a great place.
Ezekiel 37:26-8, Isaiah 43:5-6, Isaiah 2:4, Zechariah 14:9, etc.
If you really want the answer to the question you keep asking, you will need to read what I wrote in #197. (This will be the third time I have referred you to it.)
You will notice that I plainly say that Genesis 1 does NOT permit Darwinianism (MACRO-evolution).
Okay, I'm genuinely interested to know how our expectations of messiah/mashiach differ. For example, I forget the exact number, but by Christian teaching, Jesus fulfilled over three hundred messianic prophecies from the Old Testament, everything from His geneaology to the fact that He was crucified without a bone being broken. With that in mind, I've always been perplexed on what Judaism was waiting for, to put it bluntly but with zero sarcasm intended, especially since we both work from a basis of the Old Testament.
I guess what I'm confused on at the moment is this; Do you think we Christians are looking at:
a) the wrong prophecies, and thus the fact that Jesus fulfilled them is irrelevant.
b) an incomplete set of prophecies; Jesus fulfilled some but not all.
c) we're incorrectly interpreting events as fulfillment.
MM
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