Posted on 01/23/2006 4:31:58 PM PST by PatrickHenry
Scientists at the Georgia Institute of Technology have found genetic evidence that seems to support a controversial hypothesis that humans and chimpanzees may be more closely related to each other than chimps are to the other two species of great apes – gorillas and orangutans. They also found that humans evolved at a slower rate than apes.
Appearing in the January 23, 2006 issue of the Proceedings of the National Academy of Sciences, biologist Soojin Yi reports that the rate of human and chimp molecular evolution – changes that occur over time at the genetic level – is much slower than that of gorillas and orangutans, with the evolution of humans being the slowest of all.
As species branch off along evolutionary lines, important genetic traits, like the rate of molecular evolution also begin to diverge. They found that the speed of this molecular clock in humans and chimps is so similar, it suggests that certain human-specific traits, like generation time, began to evolve one million years ago - very recently in terms of evolution. The amount of time between parents and offspring is longer in humans than apes. Since a long generation time is closely correlated with the evolution of a big brain, it also suggests that developmental changes specific to humans may also have evolved very recently.
In a large-scale genetic analysis of approximately 63 million base pairs of DNA, the scientists studied the rate at which the base pairs that define the differences between species were incorrectly paired due to errors in the genetic encoding process, an occurrence known as substitution.
"For the first time, we've shown that the difference in the rate of molecular evolution between humans and chimpanzees is very small, but significant, suggesting that the evolution of human-specific life history traits is very recent," said Yi.
Most biologists believe that humans and chimpanzees had a common ancestor before the evolutionary lines diverged about 5-7 million years ago. According to the analysis, one million years ago the molecular clock in the line that became modern humans began to slow down. Today, the human molecular clock is only 3 percent slower than the molecular clock of the chimp, while it has slowed down 11 percent from the gorilla's molecular clock.
This slow down in the molecular clock correlates with a longer generation time because substitutions need to be passed to the next generation in order to have any lasting effect on the species,
"A long generation time is an important trait that separates humans from their evolutionary relatives," said Navin Elango, graduate student in the School of Biology and first author of the research paper. "We used to think that apes shared one generation time, but that's not true. There's a lot more variation. In our study, we found that the chimpanzee's generation time is a lot closer to that of humans than it is to other apes."
The results also confirm that there is very little difference in the alignable regions of the human and chimp genomes. Taken together, the study's findings suggest that humans and chimps are more closely related to each other than the chimps are to the other great apes.
"I think we can say that this study provides further support for the hypothesis that humans and chimpanzees should be in one genus, rather than two different genus' because we not only share extremely similar genomes, we share similar generation time," said Yi.
Even though the 63 million base pairs they studied is a large sample, it's still a small part of the genome, Yi said. "If we look at the whole genome, maybe it's a different story, but there is evidence in the fossil record that this change in generation time occurred very recently, so the genetic evidence and the fossil data seem to fit together quite well so far."
Would you like to respond to post 552 (concerning the link YOU posted at 451?)
A little humor goes a long way, you know.
I'm actually a comedian and have appeared on radio, TV, and screen. There is no way to escape me.
I know, it's funny. But when people ask me what I do for a living, I tell them I'm a comic. It always makes them laugh.
At this point I would like to tell a joke but you would only laugh at me.
Over and out.
While he didn't state it explicitly, I was taking his comment to refer to frauds supposedly done to support evolution. I admit now that I should not have made this assumption, as there was no wording to either state or even imply such an exclusive range... dimensio post #682
Interesting that you (dimensio)should have automatically assumed that he (zeeba) was referring to frauds done to support evolution when he didn't state that. So then, if these aritcles are dealing with fraud in the life sciences, of which evolution is a part, then you either think that evolutionists are exempt from the human foibles that afflict the rest of humanity, or that you do not consider evolutionists to be scientists, so it then wouldn't apply to them. I don't believe the first; and as for the the second......
Water under the bridge.
I already responded to most pertinent and relevant questions. I dont want to say I responded to all posts addressed to me because if a poster digressed in his/her post to me, I did not feel it opportune to me to answer it. I like to keep things in focus and on target.
Hi metmom!
I just read your email but did not respond.
I take this opportunity to thank you for the missive and for the comments in them; I agree 100%.
Once again, thanks.
Endogenous Retro Virus
Viruses that have become part of the genome. See Prediction 4.5 (about 2/3 the way down) for details.
The distribution of ERVs among the primates is illustrated there.
It's not proof of common descent, in the sense of proving the Pythagorean Theorem. However, when dealing with natural phenomena, we *never* have proof in that sense. All we have is proof in the legal sense of "beyond a reasonable doubt".
When you consider that in addition to the illustrated primate phylogenetic tree, the same kind of results have been found everywhere that genomes have been tested, doubt of common ancestry becomes highly unreasonable.
You mean like how you keep asserting that you're right and supporting this contention by posting links to (and then misquoting) articles that disagree with you?
"I already responded to most pertinent and relevant questions."
Then please explain how Lady Hope could have been with Darwin on his deathbed when the time that ALL accounts give as the only time she would have met with him was in October 1881, months before he became ill? And why does Lady Hope NOT say that he was on his death bed in any of her accounts yet YOU claim she was? And why did you at first say that Darwin's children supported the claim then run away from that claim? How can you possibly claim you have answered anything?
In all of this, the only thing I object to is the interjection of politics, liberal politics, to be precise about it, into the study of evolution, and there's plenty of it.
I don't believe we are any more closely related to Chimpanzees than any other ape for the reasons I illustrated in my analogies regarding cousins, apples, and kumquats.
Science and religion for the most part get along, but clash when it comes to evolution. I side with science, but how important is it?
Although I find evolution fascinating, I have to ask why it's so all fired important to teach it in public schools when there's a sizable portion of the population that rejects it out of hand. Furthermore, people who don't buy into it function just fine. So what's the point? Aren't there plenty of other things available to include in the curriculum besides this topic. The liberals insist on jamming it down everyone’s collective throats as a wedge issue power play. There isn't any other reason to do so.
These are interesting times... Especially with Iran right now!
Yep! So true, so true...
Logistics, schmogistics! Every time Roosie was supposed to be at Warm Springs, GA, he was really on the Secret Shuttle to Berlin. He had all the resources in the top half of the Western Hemisphere at his command.
You and Brotherhood are playing the game that "Historical Fact" is anything you want it to be. Well, so can I and mine is just as solid as yours.
>TheBrotherhood, this seems to be a core tenet of evo logic. They begin on the basis you are a liar. I say they lie in their accusations.
I will not stain myself to their lying and personal attacks by reciprocating and hurling ad hominem attacks at them. It's not in my vein to do so, despite their calling me lier and other pejorative terms.
No, I'm not. But you, by your own admission above, are "'playing the game that "Historical Fact" is anything you want it to be.'"
Yes, I am. But mine's an intentional demonstration of how far from fact your kind of "historical fact" is.
TheBrotherhood, this seems to be a core tenet of evo logic. They begin on the basis you are a liar. I say they lie in their accusations.
You could, but there would be no truth in it. TheBrotherhood has been trapped in his lies.
He asserted known falsehoods as "historical facts." When caught, he posted links from a creationist website proving that the "historical facts" were lies, but edited the quotes to make it appear as though they were supporting his contention.
Hint: when even Answers in Genesis tells you that you shouldn't use a particular argument against evolution because it's not true, you really ought not use that argument.
Any honest creationist would have to decry these transparent falsehoods. That no creationist has done so, and now one rises to his defense, tells us much about the honesty of the movement as a whole.
Talking a high-minded game is useless when posting with patent, sneering dishonesty. If you didn't know up front that the Lady Hope story was so flimsy as to be basically unfounded, contravened by most of what is known, you might at least have admitted as much when confronted with numerous refuations of the story and being able to produce nothing supporting it.
Calling something a historical fact means you can back it up without lying about what your links are actually saying. Trying to float on air in such a situation--and that's what you think you're doing here, floating on a total lack of evidence--makes a mockery of attempts to claim the high road. You can't take the high road while lying your butt off.
Again, I used to ask why a creationist can't be a man. That's too sexist for the 21st century, apparently, so I'll modify it. Why can't a creationist be an adult?
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