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
"Evolution is a LIe. There is no Physical evidence to support the Theory. "
No physical evidence? Come now, I guess scientists have just made this all up. The same class of mins who got us to the moon are so stupid they have a theory backed with not one lick of evidence? I think someone is delusional.
Good point. Of course, you remember the Clinton I did sign the double nickle repeal.
However some of us have evolved faster than others...
YES! I DISAGREE WITH THE EVOLUTIONARY TREE!
Yes, right here in these hallowed pages I've had self described experts assert the seal/whale transition.
As for your bear/dog "example", this phrase in particular, is unsubstantiated "From here, the main line of canid evolution can be traced in North America"
It's as bad as the Economist extracting himself from the bottom of a well by "assuming" a ladder.
Cynodictis (late Eocene) -- First known arctoid (undifferentiated dog/bear).
Hesperocyon (early Oligocene) -- A later arctoid. Compared to miacids like Paroodectes, limbs have elongated, carnassials are more specialized, braincase is larger. From here, the main line of canid evolution can be traced in North America, with bears branching out into a Holarctic distribution.
Cynodesmus (Miocene) -- First true dog. The dog lineage continued through Tomarctus (Pliocene) to the modern dogs, wolves, & foxes, Canis (Pleistocene).
See post 347
That is typical and representative of anti-Christian, non-conservatives like yourself who utilize this board for personal gratification.
You are no expert on faith, nor anything else for that matter from what I have seen. So, once again and for good, bye bye.
>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.<
That's what happens when I quote other self-described experts on these recurring threads.
To use a bear/dog example from this thread:
Cynodictis (late Eocene) -- First known arctoid (undifferentiated dog/bear).
Hesperocyon (early Oligocene) -- A later arctoid. Compared to miacids like Paroodectes, limbs have elongated, carnassials are more specialized, braincase is larger. From here, the main line of canid evolution can be traced in North America, with bears branching out into a Holarctic distribution.
Cynodesmus (Miocene) -- First true dog. The dog lineage continued through Tomarctus (Pliocene) to the modern dogs, wolves, & foxes, Canis (Pleistocene).
This phrase in particular, is unsubstantiated "From here, the main line of canid evolution can be traced in North America"
It's as bad as the Economist extracting himself from the bottom of a well by "assuming" a ladder.
I really doubt that a true Christian would make false claims like you do.
No, since both the rat and mouse are alive. In any case, your fish have no "substantial" differences between the two. Plus your evidence is entirely of known Intelligent Design. There is a substantial difference between the earliest vertebrate(not a worm) and homo sapiens.
Another example of Intelligent design.
1. Incorrect Distinction:
o There is a difference between micro-evolution, and macro-evolution.
o Evidence given for evolution is (almost always) evidence of micro-evolution, basically that's small changes within species.
o Everybody accepts that micro-evolution (commonly known just as "evolution") occurs.
o Evidence for (micro) evolution is not evidence for macro evolution, darwinian evolution, or big changes from one species to another.
While most of this is just bald assertion, there is the statement that "micro" evolution is "basically just small changes within species." The word "basically" in that statement is, of course, the fudge word, inserted to permit free movement of the goalposts when needed.
But lets assume for now that you take "micro" evolution as, literally, "small changes within species." This would mean, by inference, that you view "macro" evolution as speciation.
The problem here (hence the fudge word, I assume) is that speciation has been observed.
See, e.g.,
Observed Instances of Speciation, at http://www.talkorigins.org/faqs/faq-speciation.html and http://www.talkorigins.org/faqs/speciation.html
(a sample monograph) Evidence For Parallel Ecological Speciation in Scincid Lizards of the Ecumeces Skiltonianus Species Group (Squamata: Scincidae), by Jonathan Q. Richmond, and Tod W. Reeder, at http://www.bio.sdsu.edu/pub/tod/Evol2002.pdf
A concise discussion of Ring Species, at http://www.origins.tv/darwin/rings.htm
Ergo, "macro" evolution has been observed, if one takes literally a definition with speciation as the demarcation line.
In recognition of this problem, the creationist solution is to simply move the line between "micro" and "macro" into more nebulous territory. Thus, we have another creationist site stating the following:
"[W]hen creationists say they believe microevolution occurs, what they really mean is that they believe variations within a kind of animal or plant occurs. Sometimes these variations can lead to a new species, and in some cases, even a new genus. But the variations have limitations. That limitation is within the genetic information of the organism. For instance, dogs can produce numerous varieties of dogs, but they will never produce a fundamentally different kind of animal, such as a cat (similar perhaps in shape and form, but an entirely different kind of animal). It’s just not within their genetic content. In my experience, evolutionists will quickly question exactly what a "kind" is. I’ll admit that it is partially true that creationists don’t have a definite definition of what a kind is, but this shouldn’t be cause for concern. Evolutionists don’t have a definite definition on what a species is either...."
See, http://www.trueauthority.com/cvse/micromacro.htm (emphasis added).
I will assume in advance that you are in agreement with the above statement. If you are not, perhaps you could tell me why.
Based upon that assumption (which may correct me on if you wish), I also assume that you would concede that Genesis has sufficient "uncertainties" to accommodate speciation and the development of new genus or two.
Genesis is thus becoming an increasingly flexible framework, accommodating of evolution (and, according to you, an old earth) to a remakable degree.
We are apparently left only with the notion of "kinds" as the line beyond which Genesis will not permit evolution.
Perhaps you would be willing to venture a possible "definite" definition of a "kind".
And perhaps you would be willing to tell me whether you perceive hominids as a singular "kind".
It would be most interesting to continue this discussion.
Yeah, too bad ol' No-Kin had to leave us. Quite a character.
As to the examples you reference, do you (perhaps) have an alternative (non-evolutionary) explanation for the mere existence of these fossils, or for the morphological relationships apparent in the chain?
And is it your contention that the main line of canid evolution cannot be traced in North America?
You seem like a bright fellow, so no doubt you would require from me the same sort of evidence "proving" that God exists that I would require from you in order for you to "prove" that others beside yourself have a mind, and aren't just preprogrammed robots.
You go first.
So basically you can't.
No kidding. Hahahahaha
bump
You might be on to something, Larry.
A creationist trying to use logic. How cute.
I did not commit the genetic fallacy, because I did not say that the argument of the source, Eddie Snipes of the Exchanged Life Outreach, was wrong because it was posted by Eddie Snipes. (Had I said, "Ignore this source because Eddie Snipes is a banjo-playing, snake-handling hick," that would have been the genetic fallacy, as well as an ad hominem attack.) What I did do was to attack the credibility of the work, by pointing out the two more ridiculous things in it:
First, I noted that ol' Eddie committed the logical fallacy of appealing to authority; as Chuck Colson may have authority on Watergate, prison or ministry, but has no authority in the area of evolutionary biology.
Second, I was mocking Big Ed for citing to 19th Century American businessman Jay Gould. Now, the late Stephen Jay Gould was certainly an authority on evolution, but citing to Jay Gould was a laughable mistake. Moreover, describing punctuated equilibrium as the "quantum jump" was semi-literate boobery.
Finally, since you seem so enthralled by logical fallacies, I'll point out a couple. When these are made by your creationist cohorts, as I am sure they will be, I trust you'll be as enthusiastic to point them out as you were in my case:
Again, these are just a few of the standard creationist logical fallacies. I trust you'll point them out as they pop up.
I'm sorry to see that either you don't seem to be able to comprehend the implications of what is linked there, or you are willingly ignorant. In either case the result is the same. One-armed boat-rowers will only take those foolish enough to hop in the boat with them in circles. No offense, but I'm hopping out of your boat now.
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