Posted on 08/31/2005 6:18:11 PM PDT by neverdem
The first detailed genetic comparison between humans and chimpanzees shows that 96 per cent of the DNA sequence is identical in the two species. But there are significant differences, particularly in genes relating to sexual reproduction, brain development, immunity and the sense of smell.
An international scientific consortium publishes the genome of the chimpanzee, the animal most closely related to homo sapiens on Thursday in the journal Nature. It is the fourth mammal to have its full genome sequenced, after the mouse, rat and human being.
Some of the scientific analysis of the 3bn chemical "letters" of the chimp's genetic code focused on its remarkable closeness to the human genome. After 6m years of separate evolution, the differences between chimp and human are just 10 times greater than those between two unrelated people and 10 times less than those between rats and mice.
But most scientists are concentrating on the differences. The vast majority of these probably have little biological significance, said Simon Fisher of the Wellcome Trust Centre for Human Genetics at Oxford: "The big challenge for the future is to pinpoint the tiny subset of differences that account for the origins of unusual human traits, such as complex language."
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External website: Read Nature's interactive report on the chimp genome >Click here |
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The preliminary evidence suggests that the outstanding size and complexity of the human brain owes less to the evolution of new human genes than to the different way existing genes produce proteins as the human brain grows in the foetus and during infancy. Genes for transcription factors - molecules that regulate the activity of other genes and play a vital role in embryonic development - are evolving more quickly in humans than in chimps.
Three key genes involved in the human inflammatory response to disease are missing in chimps, which may explain some of the differences between the two immune systems. On the other hand humans have lost a gene for an enzyme that may protect other animals against Alzheimer's disease.
The clearest differences to emerge from the analysis are in the Y (male) sex chromosome. While the human Y chromosome has maintained its count of 27 active gene families over 6m years, some have mutated and become inactive on its chimp counterpart.
This finding contradicts the popular view that the human Y chromosome is withering away because it has no genetic "mate" with which to swap genes - a process that repairs damaged DNA on other chromosomes. Presumably an alternative repair mechanism has evolved in humans but not in chimps.
David Page of the Whitehead Institute for Biomedical Research suggested that mating habits in the two species might explain the difference. Because male and female chimps mate with multiple partners there is stronger selective pressure on sperm-producing genes and conversely less pressure on evolution to preserve other genes on the Y chromosome in the apes than in largely monogamous humans.
And what would "the most significant features" be?
The actual *nature* of the similarities and differences in the DNA, *and* the way in which the implied phylogenies superbly match the other independent lines of evidence for common descent.
Instead, the creationists ignore all that, and just hand-wave about how "similarities don't prove nothin'" (while sidestepping the fact that the DNA comparisons yield far more phylogenetic signal than mere amorphous "similarities), and mumblings about morphological features, which disingenuously tries to deny the realities of gene function, as well as the synonymous differences between genomes.
Um, you do realize that the next step in the scientific process is Law, not Fact, right? Facts are the individual pieces of data and evidence that scientific theories are based upon, not what a theory becomes.
Oh, and by the way, evolution itself is a fact, in that it is demonstrable that certain character traits can manifest over generations and be passed along to descendants. That makes evolution (little 'e') a fact, and is but one piece of evidence supporting the Theory of Evolution (big 'e').
Okay: Evolution is a Fact and a Theory, Five Major Misconceptions about Evolution, [Debunking] Creationist Claim CA201: Evolution is only a theory. It is not a fact, Introduction to Evolutionary Biology, and 29+ Evidences for Macroevolution" Scientific Proof?.
I appreciate your heartfelt apology, that's mighty big of you.
Have a great evening!
Thanks, you too.
Hey, thats down, they used to peg it at 98% But that was probably just in the New England university scene.
Thanks for the ping!
Here's an idea- before you come onto these threads and start making inane claims about the theory of evolution, perhaps you should actually go and learn what the TOE says.
That way, you won't end up looking like an idiot.
Okay, fair enough.
And my apologies at the moment for wasting your time.
No apology needed -- the only person with the power to waste my time is myself. ;-)
bonobo bump
I remember reading the identical statement ten years ago.
Why is this news again?
I'm almost afraid to ask. What's the purpose of "re-publishing it" so to speak?
HHAHAHAHAHAHaH thats soooooo funny ..Just spit out my iced tea here...AHHHHHHHHHHHHHHHHHH
What % difference would you guess there is between Einstein and a moron like Michael Moore?
Bump for later... time to hit the rack tonight.
But that's an Orangatan, not a chimp. I think the Irish are descended from a common ancestor of those, at least the Kennedy clan.
Yes there has. But, the benefits weren't worth the design headaches.
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