Chromosome 2

Posted by Seer 8 years, 2 months ago to Science
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Yesterday, I was searching the Internet for possible answers to why the mythology of the ancient Sumerians was, in one very important respect, different from the mythology of ancient Egypt.
One thing led to another, and I came across something I had never known before: Chromosome 2.
We are told that the DNA of humans and chimps are 98. something % alike; we are not told that the haploid number of chromosomes in the genus Homo is one less than in other primates.
Apparently there was a random "mutation"---and it probably occurred in more than one individual---that caused the fusion of two chromosomes, resulting in the second largest chromosome in the cell structure of hominids.
Some implications of this occurrence are:
1. It gives credence to the "cladogenesis" theory of evolution: "Cladogenesis is the process by which a species splits into two distinct species, rather than one species gradually transforming into another."--Wikipedia
2. An abnormality associated with Chromosome 2 is synesthesia: "a neurological phenomenon in which stimulation of one sensory or cognitive pathway leads to automatic, involuntary experiences in a second sensory or cognitive pathway." From here:
http://en.wikipedia.org/wiki/Synesthe...
3. Apply cladogenesis to rampant and legal abortion, and you have another reason it is illegal.


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  • Posted by $ blarman 8 years, 2 months ago in reply to this comment.
    I don't support the notion of evolutionary origin, so I'm going to leave him to offer his own defense. Personally, I'm not really sure how one would be either support or denial for abortion, so I'm not going to comment further.
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  • Posted by 8 years, 2 months ago in reply to this comment.
    I agree.

    Do you not believe in evolution, Dob? My reply has always been; How can you not believe in evolution?
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  • Posted by Dobrien 8 years, 2 months ago in reply to this comment.
    As a man it is none of my business unless I participated in the pregnancy. That said it is a very traumatic event often with long term emotional baggage attached. A reckless sexual behavior that does not anticipate results has its consequences. Birth control and consciousness could avoid many abortions. Rape or incest or medical issues is a different story.
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  • -1
    Posted by 8 years, 2 months ago in reply to this comment.
    It is most definitely a valid question; and I'm sure the evolutionists are on it, as we speak. I can't do all their work for them!!

    Don't you think Dob's refutation of the validity of evolution is a pretty pi**poor argument for the legality of abortion?
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  • Posted by 8 years, 2 months ago in reply to this comment.
    I hope, Dob, you are not bringing a case for the morality of abortion?
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  • Posted by 8 years, 2 months ago in reply to this comment.
    The importance of the "position" of the genetic structure is why I brought up the anomaly known as "synesthesia":

    An abnormality associated with Chromosome 2 is synesthesia: "a neurological phenomenon in which stimulation of one sensory or cognitive pathway leads to automatic, involuntary experiences in a second sensory or cognitive pathway."

    There are at least two implications here: a. Could this anomaly reflect human's (but not a chimp's) ability to conceptualize: "...the stimulation of one...cognitive pathway, leads to the involuntary stimulation of a second...cognitive pathway." and b. Could synesthesia occur if the two chromosomes were separate?
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  • Posted by 8 years, 2 months ago in reply to this comment.
    I happen to believe in the theory of evolution and can't understand why any other doesn't.
    But that wasn't the purpose of this topic.

    The presence of Chromosome 2 implies that even though 98.something % of human and chimp genes are alike (and what exactly does that mean: genes---are they talking about "codes" for enzyme production?) it is the position of those "genes/codes" that determine attributes of species, not their existence itself.
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  • Posted by $ blarman 8 years, 2 months ago in reply to this comment.
    There are certain similarities in nearly all animals. If you look at the general skeletal structure of most vertebrates they show remarkably similarities. Many animals share the same basic organ layout and complex animals share many of the same systems and glands - even if there are minor changes from Class to Class. What I caution against is the jump that many make to try to infer that there is more than just similarity because creationists argue that similarity is the sign of a single guiding hand. If you want to take a Darwinian approach, that's fine, but realize that without a fossil record to support it, it isn't even a theory - it's a daydream.
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  • Posted by Dobrien 8 years, 2 months ago in reply to this comment.
    (1) Is the 99% Human/Chimp DNA-similarity statistic accurate? While recent studies have confirmed that certain stretches of human and chimp DNA are on average about 1.23% different, this is merely an estimate with huge caveats. A recent news article in Science observed that the 1% figure "reflects only base substitutions, not the many stretches of DNA that have been inserted or deleted in the genomes."1 In other words, when the chimp genome has no similar stretch of human DNA, such DNA sequences are ignored by those touting the statistic that humans and chimps are only 1% genetically different. For this reason, the aforementioned Science news article was subtitled "The Myth of 1%," and printed the following language to describe the 1% statistic:

    "studies are showing that [humans and chimps] are not as similar as many tend to believe";
    the 1% statistic is a "truism [that] should be retired";
    the 1% statistic is "more a hindrance for understanding than a help";
    "the 1% difference wasn't the whole story";
    "Researchers are finding that on top of the 1% distinction, chunks of missing DNA, extra genes, altered connections in gene networks, and the very structure of chromosomes confound any quantification of 'humanness' versus 'chimpness.'"
    Indeed, due to the huge caveats in the 1% statistic, some scientists are suggesting that a better method of measuring human/chimp genetic differences might be counting individual gene copies. When this metric is employed, human and chimp DNA is over 5% different. But new findings in genetics show that gene-coding DNA might not even be the right place to seek differences between humans and chimps.
    But there is a deeper question: (2) If humans and chimps were truly only 1% different at the genetic level, why should that demonstrate common ancestry?
    similarities in key genetic sequences may be explained as a result of functional requirements and common design rather than mere common descent. We might reasonably ask the evolutionist why the 1% difference value is considered powerful evidence for Darwinian evolution, and at what point does the comparison cease to support Darwinian evolution? What about 2% different? 3%? 5%? 10%? Is there an objective metric for falsification here, or is PBS putting forth a fallacious argument for human / chimp common ancestry?

    the truth is that the percent difference says nothing about whether humans and chimps share a common ancestor. The percent genetic similarity between humans and apes does not demonstrate Darwinian evolution.
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  • Posted by Dobrien 8 years, 2 months ago in reply to this comment.
    The ancient genomes, one from a Neanderthal and one from a different archaic human group, the Denisovans, were presented on 18 November at a meeting at the Royal Society in London. They suggest that interbreeding went on between the members of several ancient human-like groups living in Europe and Asia more than 30,000 years ago, including an as-yet unknown human ancestor from Asia.

    “What it begins to suggest is that we’re looking at a ‘Lord of the Rings’-type world — that there were many hominid populations,” says Mark Thomas, an evolutionary geneticist at University College London who was at the meeting but was not involved in the work.

    The first Neanderthal and the Denisovan genome sequences revolutionized the study of ancient human history, not least because they showed that these groups interbred with anatomically modern humans, contributing to the genetic diversity of many people alive today.

    All humans whose ancestry originates outside of Africa owe about 2% of their genome to Neanderthals; and certain populations living in Oceania, such as Papua New Guineans and Australian Aboriginals, got about 4% of their DNA from interbreeding between their ancestors and Denisovans, who are named after the cave in Siberia’s Altai Mountains where they were discovered. The cave contains remains deposited there between 30,000 and 50,000 years ago.

    Those conclusions however were based on low-quality genome sequences, riddled with errors and full of gaps, David Reich, an evolutionary geneticist at Harvard Medical School in Boston, Massachusetts said at the meeting. His team, in collaboration with Svante Pääbo at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, have now produced much more complete versions of the Denisovan and Neanderthal genomes — matching the quality of contemporary human genomes. The high-quality Denisovan genome data and new Neanderthal genome both come from bones recovered from Denisova Cave.

    The new Denisovan genome indicates that this enigmatic population got around: Reich said at the meeting that they interbred with Neanderthals and with the ancestors of human populations that now live in China and other parts of East Asia, in addition to Oceanic populations, as his team previously reported. Most surprisingly, Reich said, the new genomes indicate that Denisovans interbred with another extinct population of archaic humans that lived in Asia more than 30,000 years ago, which is neither human nor Neanderthal.

    The meeting was abuzz with conjecture about the identity of this potentially new population of humans. “We don’t have the faintest idea,” says Chris Stringer, a paleoanthropologist at the London Natural History Museum, who was not involved in the work. He speculates that the population could be related to Homo heidelbergensis, a species that left Africa around half a million years ago and later gave rise to Neanderthals in Europe. “Perhaps it lived on in Asia as well,” Stringer says.
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  • Posted by $ Olduglycarl 8 years, 2 months ago in reply to this comment.
    And they all ended up in governments across the world...laughing but maybe my name for them is apt after all..."parasitical humanoid" neanderthalensis?
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  • Posted by $ blarman 8 years, 2 months ago in reply to this comment.
    First of all that because most of the chromosomes are similar that somehow that means the resulting organisms are also similar in origin. The amount of information encoded on any chromosome fills libraries, yet the argument is that because 9 out of ten libraries are similar that the origin of the tenth can be more or less ignored. The effort required for the creation of even one chromosome is staggering and given the inherent self-replication and self-healing exhibited in DNA, the notion that a mutation would cause a gene split of this magnitude is of such a ridiculous probability not just once but millions of times...? Humans also share 60% similarity with fruit flies (http://www.eupedia.com/forum/threads/...) - yet no one argues that humans are going to sprout wings or mate and die.

    The second is the mutation theory of genesis. The problems with this is that we see precisely zero examples of mutating genes in the world around us. If it happened for millions (or billions) of years as evolutionists claim, why did it stop? Why do we see nothing in the fossil record and nothing in present zoology? A far more likely conclusion is that it has never happened at all.
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  • Posted by fivedollargold 8 years, 2 months ago in reply to this comment.
    They might have died out from some disease to which humans had immunity but they didn't. However, I suspect they were killed off by humans except for some of the Neanderthal women kept as sex slaves. It's possible they remain alive only through a small amount of their DNA preserved in some modern humans.
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  • -3
    Posted by 8 years, 2 months ago in reply to this comment.
    I think the downvoter is one who doesn't want to give up her "right" to choose abortion.
    But of course she doesn't want to come forward with her objections.
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  • Posted by 8 years, 2 months ago in reply to this comment.
    I didn't know this before my recent searches, but it turns out Neanderthal is included in the genus Homo, so would have 23 haploid number of chromosomes. Some researchers think Neanderthal may have been a separate species: Homo neanderthalensis, some include him as a subspecies: Homo sapiens neanderthalensis. As a subspecies he could have interbred with H. sapiens sapiens (gotta say it twice) but I don't know if he could have as a separate species. Anyway, that really is more than I need to know--gets confusing from there on in. I do think H. neanderthalensis probably died out as a result of rapid climate changes, not having the advanced mental capability of H. sapiens sapiens, who was able to adapt more quickly.
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  • Posted by fivedollargold 8 years, 2 months ago
    Given that humans of European ancestry have a small percentage of Neanderthal DNA, one must conclude they also had 23 pairs of chromosomes. Does this support the clad theory?
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  • Posted by $ blarman 8 years, 2 months ago
    Not really sure why people are downvoting just for presenting information, even though I personally question many of the underlying suppositions.
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  • -2
    Posted by 8 years, 2 months ago
    Forgot to add "...you have another reason abortion is immoral."
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