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."
Hey, PH.
Thanks for responding to my post at long last!
That post #106 is my post. It has potential for what, Doc?
>Thank you and goodnight.
Good night.
Just one creation story. I think I made my point from a year or two ago so that I don't need to post them very often.
What I am having fun posting now is some of the fossil man data. Many on these threads have never seen that actual data that they are denying exists or that has no meaning.
Whoa! Here's one now! (Cute little guy, too!)
Site: Buxton Limeworks, Taung, South Africa (1)
Discovered By: M. de Bruyn 1924 (1)
Estimated Age of Fossil: 2.3 mya * determined by Faunal & geomorphological data (1, 4, 5)
Species Name: Australopithecus africanus (1, 3, 7, 8)
Gender: Unknown (1)
Cranial Capacity: 405 (440 as adult) cc (1, 3)
Information: First early hominid fossil found in Africa (7, 8)
Interpretation:
See original source for notes:
http://www.mos.org/evolution/fossils/fossilview.php?fid=27
>But I'm hoping for even better.
>I'm trying, oh Master, I'm trying.
I'll try, O Master! I'll try.
What is you're talking about, anyway. What is this potential of mine you're talking about? Am I in? Have I, out of the blue sky become a "somebody?"
LOL!
The branching divergence of evolutionary trees tends to mean we should be about equally unrelated to all plants. This tends to be approximately true. Some creationists have tried to spin this "in their favor" by citing how humans and monkeys are equally unrelated to fish. This plays on the misconception that since the monkey is "lower" than man and the fish is "lower" than the monkey, the monkey should somehow fall between the fish and the man in relatedness. What actually happens is that modern fish, man, and monkeys are all "modern" but have diverged in a pattern like the one below.
Man Monkey Fish
| | |
| | |
| | |
--------------- |
| |
| |
| |
|<==(Ancient amphibians) |
-----------------------------
| (Ancient fish)
|
|
Looked at properly, there's an ancient split between true fish and the ancestors of amphibians. Every modern thing that comes off one side of that branch has been diverging for about the same time from everything descended from the other side of that split. That's what we see and what we should see.
>Just for your edification, theories do not graduate to laws, the two serve different purposes.
Coyoteman just explained to me this difference between theory and law. He said a law is a generalization based on observation and can stand on its own. A theory starts from a well thought-out hypothesis and after testing and retesting it may become a theory. I hope I'm not misquoting him.
It's kind of an honor roll.
Excellent point!
You're good. You can make mince meat out of these evolutionist cultists.
>Yahoo! They're back!
Who's back?
Nope. Laws are just mathematical descriptions of empirical regularities. For example physical objects attract each other with a force that is proportional to the product of their masses and the inverse square of the distance between them. That's the law of gravity.
Theories attempt to explain the mechanisms behind laws. The theory of gravity seeks to find precisely what causes masses to attract each other, i.e. curves in the fabric of spacetime, microscopic particles called gravitons, etc.
Are you still repeating the well-debunked lie that Darwin repented on his deathbed?
I'll give you this. Your homepage goal about uniting all Christians is something I've been wondering why it isn't more prevalent. As a non-Christian, I've often been dumbstruck by how often Christians fight and argue with each other about their particular denomination. Let alone the whole Catholic vs. Protestant thing.
So, at least your heart is in the right place. If I were a Christian, I'd be right behind you in that effort, 100%. Then, jerks like me would have to stop pointing out the ridiculous nature of modern Christianity and all it's petty bickering.
But I digress. About those brainless chimps...
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