Posted on 05/20/2003 2:05:10 PM PDT by kkindt
A new report argues that chimpanzees are so closely related to humans that they should be included in our branch of the tree of life. Chimpanzees and other apes have historically been separated from humans in classification schemes, with humans deemed the only living members of the hominid family of species
(Excerpt) Read more at news.nationalgeographic.com ...
You've got the cart before the horse, sir. Theories don't have to be proven false, theories by definition are unproven suppositions. Until a theory is proven true, it remains an hypothesis, a guess. The onus is on you to prove your conjecture. Indeed, your very question is a ruse.
Thank you for so eloquently proving my point. Last time I checked, NASA makes those little ship thingies that leave the earth. :o)
Heh.... Some of us just think it is pretty fascinating... You on the other hand, only worry about whether or not you are going to have to share something with a monkey.
If you guys would have read the article, it clearly does not say "Chimps Now to be Considered Humans". It just means that somewhere 5 million years back on the tree, there are branches close enough to consider them on the same Genus.... not the same species. We can't breed, let alone marry.... don't worry yourself about it.
Oh brother. Yes, we do leave the earth.... Relatively speaking, our space flights have brought us great leaps, but relative to how big a place the universe really is, not much higher than a pole vaulter.
Funny, we share the same fear. That and my additional fear that they will think we don't know that "scares" is not possessive.
And as we all know, there is what we call "exact science", hypotheses that can be proved, or reproduced through experiment, etc. There are different forms of science. The people who try to present these ape/man/origin-of-man theories as exact science need to be exposed. And judging by the rage of some these pseudo scientists, I can see they don't like to have their misrepresentations torn apart by logic and reason. They present their findings, but festoon them in a fashion that attempts to confuse the reader into thinking their theory has been proven by exact science, it's all smoke and mirrors. That chimps have a 99% similar DNA to humans means nothing to the origin of man, especially when you consider that cats have a 90% similar DNA to humans. And even more so when you consider the fact that science itself has never held DNA to be the indicator of human origin. There are so many presumptions, presppositions and holes in this "scientific" argument that it's like Swiss cheese. As for me, science itself proves the existence of God, just as the Masterpiece proves the existence of an artist. Pax Chrisi.
Uh huh.... doesn't surprise me, cats and humans are both mammals. The distinctions become smaller the closer you get.... kindof like taking a distance and with each step cutting it in half.
They present their findings, but festoon them in a fashion that attempts to confuse the reader into thinking their theory has been proven by exact science...
That is bull. No one educated at all believes that theories about things as massive and unrepeatable as creation or evolution are fully known, proven, or that there will be no more mysteries or surprises or future better theories.
As for me, science itself proves the existence of God, just as the Masterpiece proves the existence of an artist.
Uh huh.... OK - Some still make a life out of finding out a couple more details. For some, just knowing more about it is cool.
I would bet on that, have you ever taken a close look at CARVEL.
I would not bet on that, have you ever taken a close look at CARVEL.
Nope. Theories get proven false all the time. What you cannot do is prove a theory true in a strict sense; the best you can do is 1) build a circumstantial case for it via several lines of evidence, and 2) prove all the serious competing theories false."Is that why when I ask for ONE piece of scientifically verifiable evidence that proves that evolution is false, the creationists become VERY quiet, or do their best to misrepresent it to fit their silly notions?"
You've got the cart before the horse, sir. Theories don't have to be proven false, theories by definition are unproven suppositions. Until a theory is proven true, it remains an hypothesis, a guess. The onus is on you to prove your conjecture. Indeed, your very question is a ruse.
[Kenny Bunk:] Yo Junior, we share 90% of our DNA with watermelons. So does that mean we must invite chimps to our 4th of July picnic?
[TheCrusader:] That chimps have a 99% similar DNA to humans means nothing to the origin of man, especially when you consider that cats have a 90% similar DNA to humans.
LOL! OK you two, your homework for tonite is to read post 149. There'll be a quiz on this in the morning. :-)
They'll declare unborn babies as nothing but part of the mother's "tissue" even though it can be proven the baby has it's own DNA. DNA evidence is useful when you want to say humans are nothing more than some kind of animal that should have certain rights because of it ---but DNA cannot be used when it comes to the unborn humans.
Humans have 23 pairs of chromosomes ---chimps and gorillas have 24 pairs. How many pairs of chromosomes did the "common ancestor" have? Was it 23 or 24 pairs? How do you "evolve" missing or added chromosomes ---that would happen all at one time. If a chimpanzee gives birth to a creature with 23 chromosomes, that offspring isn't going to be a well-formed chimpanzee able to survive well. Evolve would imply the genetic material changes little by little --not some big loss of two chromosomes at once but I don't see how they'd go away gene by gene.
It's the definition of "genus" that's important here.
And you can cite a source for this statement? I doubt it seriously because it ain't true.
Many of the folks on these threads would be really suprised by the methods researchers have developed over the decades to work out sticky problems such as dating objects. And they'd also be surprised at the lengths researchers go to to double check any findings they might get. Sometimes I get the impression the less scientifically literate on these threads think scientists get their information from divine revelation, or from pulling numbers out of thin air. The LSL fail to understand the checks and balances used by scientists.
Genus, not species.
How many have you invented?
By your criterion, most humans don't "count" either.
The common ancestor had 24 chromosomes.
If you look at the gene sequences, you'll find that Chromosome 2 in humans is pretty much just 2 shorter chimpanzee chromosomes pasted end-to-end, with perhaps a slight bit of lost overlap:
(H=Human, C=Chimpanzee, G=Gorilla, O=Orangutan)
Somewhere along the line, after humans split off from the other great apes, or during the split itself, there was an accidental fusion of two chromosomes, end-to-end. Where there used to be 24 chromosomes, now there were 23, but containing the same total genes, so other than a "repackaging", the DNA "instructions" remained the same.
If a chimpanzee gives birth to a creature with 23 chromosomes, that offspring isn't going to be a well-formed chimpanzee able to survive well.
It is if the same genes are present, which they would be in the case of a chromosome fusion.
Evolve would imply the genetic material changes little by little --not some big loss of two chromosomes at once but I don't see how they'd go away gene by gene.
Tacking two chromosomes together end-to-end is not a "big loss" of genes, and it really is a "little by little" change in the total genetic code. It's just been "regrouped" a bit. Instead of coming in 24 "packages", it's now contained in 23, but the contents are the same.
So how, you might ask, would the chromosomes from the first 23-chromosome "fused" individual match up with the 24 chromosomes from its mate when it tried to produce offspring? Very well, thanks for asking. The "top half" of the new extra-long Chromosome 2 would adhere to the original chromosome (call it "2p") from which it was formed, and likewise for the "bottom half" which would adhere to the other original shorter chromosome (call it "2q"). In the picture above, imagine the two chimp chromosomes sliding over to "match up" against the human chromosome. The chimp chromosomes would end up butting ends with each other, or slightly overlapping in a "kink", but chromosomes have overcome worse mismatches (just consider the XY pair in every human male -- the X and the Y chromosome are *very* different in shape, length, and structure, but they still pair up).
In fact, the "rubbing ends" of the matched-up chimp chromosomes, adhering to the double-long human-type chromosome, would be more likely to become fused together themselves.
For studies in which recent chromosome fusions have been discovered and found not to cause infertility, see:
Chromosomal heterozygosity and fertility in house mice (Mus musculus domesticus) from Northern Italy. Hauffe HC, Searle JB Department of Zoology, University of Oxford, Oxford OX1 3PS, United Kingdom. hauffe@novanet.itIn that last reference, the Przewalski horse, which has 33 chromosomes, and the domestic horse, with 32 chromosomes (due to a fusion), are able to mate and produce fertile offspring.An observed chromosome fusion: Hereditas 1998;129(2):177-80 A new centric fusion translocation in cattle: rob (13;19). Molteni L, De Giovanni-Macchi A, Succi G, Cremonesi F, Stacchezzini S, Di Meo GP, Iannuzzi L Institute of Animal Husbandry, Faculty of Agricultural Science, Milan, Italy.
J Reprod Fertil 1979 Nov;57(2):363-75 Cytogenetics and reproduction of sheep with multiple centric fusions (Robertsonian translocations). Bruere AN, Ellis PM
J Reprod Fertil Suppl 1975 Oct;(23):356-70 Cytogenetic studies of three equine hybrids. Chandley AC, Short RV, Allen WR.
Meanwhile, the question may be asked, how do we know that the human Chromosome 2 is actually the result of a chromsome fusion at/since a common ancestor, and not simply a matter of "different design"?
Well, if two chromsomes accidentally merged, there should be molecular remnants of the original chromosomal structures (while a chromosome designed from scratch would have no need for such leftover "train-wreck" pieces).
Ends of chromosomes have characteristic DNA base-pair sequences called "telomeres". And there are indeed remnants of telomeres at the point of presumed fusion on human Chromosome 2 (i.e., where the two ancestral ape chromosomes merged end-to-end). If I may crib from a web page:
Telomeres in humans have been shown to consist of head to tail repeats of the bases 5'TTAGGG running toward the end of the chromosome. Furthermore, there is a characteristic pattern of the base pairs in what is called the pre-telomeric region, the region just before the telomere. When the vicinity of chromosome 2 where the fusion is expected to occur (based on comparison to chimp chromosomes 2p and 2q) is examined, we see first sequences that are characteristic of the pre-telomeric region, then a section of telomeric sequences, and then another section of pre-telomeric sequences. Furthermore, in the telomeric section, it is observed that there is a point where instead of being arranged head to tail, the telomeric repeats suddenly reverse direction - becoming (CCCTAA)3' instead of 5'(TTAGGG), and the second pre-telomeric section is also the reverse of the first telomeric section. This pattern is precisely as predicted by a telomere to telomere fusion of the chimpanzee (ancestor) 2p and 2q chromosomes, and in precisely the expected location. Note that the CCCTAA sequence is the reversed complement of TTAGGG (C pairs with G, and T pairs with A).Another piece of evidence is that if human Chromosome 2 had formed by chromosome fusion in an ancestor instead of being designed "as is", it should have evidence of 2 centromeres (the "pinched waist" in the picture above -- chromosomes have centromeres to aid in cell division). A "designed" chromosome would need only 1 centromere. An accidentally "merged" chromosome would show evidence of the 2 centromeres from the two chromosomes it merged from (one from each). And indeed, as documented in (Avarello R, Pedicini A, Caiulo A, Zuffardi O, Fraccaro M, Evidence for an ancestral alphoid domain on the long arm of human chromosome 2. Hum Genet 1992 May;89(2):247-9), the functional centromere found on human Chromosome 2 lines up with the centromere of the chimp 2p chromosome, while there are non-functional remnants of the chimp 2q centromere at the expected location on the human chromosome.
As an aside, the next time some creationist claims that there is "no evidence" for common ancestry or evolution, keep in mind that the sort of detailed "detective story" discussed above is repeated literally COUNTLESS times in the ordinary pursuit of scientific research and examination of biological and other types of evidence. Common ancestry and evolution is confirmed in bit and little ways over and over and over again. It's not just something that a couple of whacky anti-religionists dream up out of thin air and promulgate for no reason, as the creationists would have you believe.
Think of that! A fruity snack that treats you badly at the 4th of July picnic! It could change the world as we know it. But, my scientific colleagues, you have avoided my question about inviting the chimp to that 4th of July Picnic.
I maintain that if the chimp is a properly registered Democrat (and with Motor Voter there isn't a damn thing to prevent that), then he/she should be invited. But no long speeches.
Well, feathers evidently came first -- and were used as insulation by warm-blooded or semi warm-blooded dinosaurs. There is strong evidence that even semi-formed wings enabled the bearer to escape predation by helping it climb trees (juvenile birds of some species still use this method).
I thought they already did.
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