Posted on 09/26/2005 3:27:53 AM PDT by Crackingham
When scientists announced last month they had determined the exact order of all 3 billion bits of genetic code that go into making a chimpanzee, it was no surprise that the sequence was more than 96 percent identical to the human genome. Charles Darwin had deduced more than a century ago that chimps were among humans' closest cousins. But decoding chimpanzees' DNA allowed scientists to do more than just refine their estimates of how similar humans and chimps are. It let them put the very theory of evolution to some tough new tests.
If Darwin was right, for example, then scientists should be able to perform a neat trick. Using a mathematical formula that emerges from evolutionary theory, they should be able to predict the number of harmful mutations in chimpanzee DNA by knowing the number of mutations in a different species' DNA and the two animals' population sizes.
"That's a very specific prediction," said Eric Lander, a geneticist at the Broad Institute of MIT and Harvard, and a leader in the chimp project.
Sure enough, when Lander and his colleagues tallied the harmful mutations in the chimp genome, the number fit perfectly into the range that evolutionary theory had predicted.
SNIP
Evolution's repeated power to predict the unexpected goes a long way toward explaining why so many scientists are practically apoplectic over the recent decision by a Pennsylvania school board to treat evolution as an unproven hypothesis, on par with "alternative" explanations such as Intelligent Design (ID), the proposition that life as we know it could not have arisen without the helping hand of some mysterious intelligent force.
SNIP
"What makes evolution a scientific explanation is that it makes testable predictions," Lander said. "You only believe theories when they make non-obvious predictions that are confirmed by scientific evidence."
(Excerpt) Read more at washingtonpost.com ...
***I have and I understand it, would you care to elaborate?***
Sorry. It's Nature, not Science. My mistake. Interesting you have it in Science... :)
Nonetheless, I refer you to Cheng et al, Nature: 88 2005.
Here's the full ref and abstract.
_____
Nature. 2005 Sep 1;437(7055):88-93.
A genome-wide comparison of recent chimpanzee and human segmental duplications.
Cheng Z, Ventura M, She X, Khaitovich P, Graves T, Osoegawa K, Church D, DeJong
P, Wilson RK, Paabo S, Rocchi M, Eichler EE.
Howard Hughes Medical Institute, Department of Genome Sciences, University of
Washington School of Medicine, 1705 NE Pacific Street, Seattle, Washington
98195, USA.
We present a global comparison of differences in content of segmental
duplication between human and chimpanzee, and determine that 33% of human
duplications (> 94% sequence identity) are not duplicated in chimpanzee,
including some human disease-causing duplications. Combining experimental and
computational approaches, we estimate a genomic duplication rate of 4-5
megabases per million years since divergence. These changes have resulted in
gene expression differences between the species. In terms of numbers of base
pairs affected, we determine that de novo duplication has contributed most
significantly to differences between the species, followed by deletion of
ancestral duplications. Post-speciation gene conversion accounts for less than
10% of recent segmental duplication. Chimpanzee-specific hyperexpansion (> 100
copies) of particular segments of DNA have resulted in marked quantitative
differences and alterations in the genome landscape between chimpanzee and
human. Almost all of the most extreme differences relate to changes in
chromosome structure, including the emergence of African great ape subterminal
heterochromatin. Nevertheless, base per base, large segmental duplication events
have had a greater impact (2.7%) in altering the genomic landscape of these two
species than single-base-pair substitution (1.2%).
Exactly - hence creationism is incorrect.
I know the article. I have read it and I have read the abstract (I noted your "Science" as irrelevant - I personally know one of the authors). My question to you was concerning your post #44. What is your point?
You've got the time machine in reverse this morning. The prediction was made before the facts were even known to exist in this case. At least we know you don't do science.
But it is evidence that they both descended from 'common ground', so to speak.
Mr.Grumpy is a troll.
The talk origin tract indicattes that repeat elements should always be seen in organisms with a common ancestor. In this case there are duplication events in common ancestors, but not human, The talk origin tract would make one think this contradicts common descent.
It doesn't take in to account there can be deletions such as observed whereby Gorilla, Chimp and Orangutan have elements in common, but not human.
As more genomes are sequences and analyzed there will be a lot of these sort of ostensible descrepancies.
Articles meant as evangelical polemic, such as cited here, and mindlessly parrotted here by some, present a false picture of molecular evolution's complexity.
But they're not. They're measuring mutations in humans and chimps, which occur according to evolutionary predictions, which conclusively indicate not only common descent, but when, within a relatively short time frame, humans and chimps shared our last common ancestor.
Evolution "scientists" must be part kangaroo!
We're not "part" anything. We did, however, share a common ancestor with kangaroos, probably around 110 million years ago when our placental ancestors branched off.
I think they're succumbing to the temptation to arrange the facts to fit their theory
What's your explanation for why mutation rates in both nuclear and mtDNA exactly fit evolutionary predictions? Do you have an explanation?
Then add in having the same misspellings, grammar errors, and ink smudges and spills in the same places......
"repeat elements should always be seen in organisms with a common ancestor"
Supply a referenced quote for this, please.
I know. Perhaps some nice chocolaty flavored Exlax.
It proves common descent -- not that we and chimps had a similar ancestor, but that we share a common ancestor. How do we know this? Well, for one of many reasons, because DNA mutates at a remarkably constant rate. Now some parts of DNA code for things that we select for on a daily basis -- someone born with no arms is less likely to live than someone with two arms, so a mutation that codes for no arms quickly dies out. But most mutations have no effect on an individuals ability to survive, and those survive, and are measurable. By comparing the mutations present in both human and chimp DNA, we can tell just how long it was we branched off (imagine a genetic stop watch) -- and amazingly, the date we get is exactly what we find in the fossil record.
Read the t.o referenced article. Itchyman has parrotted it in the past and linked to it and today Patrick Henry linked to it.
Indeed, many argue that chimps and bonobos evolved after humans did.
On it's face, your comment is not only silly, but nonsensical. Maybe that's what you meant and my receiving it was limited by the medium.
They just haven't demonstrated the ability. When you are on a debate team, you have to be able to argue both sides of a question equally well. If you participate in a discussion, you need to be able to state your opponent's position accurately.
These are elementary qualifications that creationists fail to meet when arguing against evolution.
Not really. You made the claim that "nothing can come from nothing". Isn't that exactly what creationism tries to claim occurred? Current cosmological, geological, and biological theories make no such claim.
Man and Chimp were created with enough difference to belong to two different 'kinds' just like God created them.
Who is warping, twisting, and misrepresenting science in their arguments?
Actually, if you read the article, you will see that it pertains to the statistical analysis of epidemiological and medical studies, not science research in general. I made my points when that thread was current on FR. But then again, anti-science sentiments run deep in the creationist camp so anything else that can be warped to their agenda will be warped.
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