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Human Phenomenon

  1. Oct 23, 2009 #1
    Chimpanzees share 98.4% of our DNA, does that mean that Chimps can eventually evolve into a human form of biological life.

    Questions does this 1.6% difference mean that chimps lack the DNA sequences to eventually evolve or are the existence of the DNA sequences just not present and they don’t have the ability to evolve.

    My problem is with evolution of man and by no means am I bringing a benevolent all knowing entity into this conversation to explain the existence of man.

    Can this question be answered by pure science, objectively?

    Some would say that our fossil record is our proof.

    This theory of evolution based the fact that we looked like Ramapithecus lufagensis

    Did we evolve from a lower form of life?

    Do chimps have the DNA to evolve or do they lack the DNA and they will always be chimps?

    This is not homework :) I just struggle with my own mortality.
  2. jcsd
  3. Oct 23, 2009 #2


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    Chimps and humans share a common ancestor. Chimps did not "turn into humans" and never will. They will branch in their own directions.

    Every species has the ability to evolve. Some tend to stand still for a long time because in their environment any modification would be selected against. They reach a stalemate in the evolutionary arms race so to speak.

    The fossil record is one peice of evidence. There is much more from just about every other branch of science.

    No. Not sure what you mean by this.

    "Lower" and "Higher" are subjective.
    Last edited: Oct 23, 2009
  4. Oct 23, 2009 #3
    Thanks for the reply, I really appriciate your input.

    Perhaps you or someone can answer this question strait forward, does the chimp difference of 1.6%of DNA, is that a lack of DNA or is the DNA there in some other form that would eventually from present to 5000yrs in the future, would a chimp today evolve? or could they evolve?

    Is evolution real or not in a sense that would give a chimp the ability of speach 5000yrs from now?

    In this one species; is evolution possible? Can it be proven other than someone answering "yes"
  5. Oct 23, 2009 #4


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    That difference is when you line up the genome and cleverly compare each individual base-pair. That doesn't mean a whole lot to explain *how* we are different. We have trouble enough finding the differences between humans.

    Evolution is real in the sense that genetic mutations, advantageous combinations of existing traits and heredity can cause members of a species to inherit traits which give it (and potentially its offspring) a reproductive advantage over others in the same species. So eventually the creatures with the stronger traits overwhelm the previous "baseline" population or cause them to diverge.

    This has been proven. When nature does the selection it's called natural selection. When humans are involved in selectively breeding it's called artificial selection.

    So for example, different breeds of dogs are an example of evolution guided by human beings.

    Could we breed a talking dog? Probably not. That evolutionary pathway is probably closed for them. It's hard to say for chimps.
    Last edited: Oct 23, 2009
  6. Oct 23, 2009 #5


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    As said above, all animals evolve, just at their own pace and in their own direction. Chimps included.
    Odd way of phrasing it. Yes, evolution is real. A chimp could evolve speech (probably not in 5,000 years), but whether it did or not doesn't have anything to do with the fact that evolution is real. Evolution does not have a pre-defined direction/goal.
    How, exactly, would you like to have it proven to you? What sort of evidence/logic would you accept?
  7. Oct 23, 2009 #6
    I suggest you revisit the source of your data. First, make a determination as to whether a 1.6% difference is large or small. Next, do a comparison of other sequences that may be closer (I don't have any in mind - no agenda present), and post your findings?
  8. Oct 26, 2009 #7
    If human and chimp DNA was even 96% homologous? What would that mean? Would it mean that humans could have 'evolved' from a common ancestor with chimps? The amount of information in the 3 billion base pairs in the DNA in every human cell has been estimated to be equivalent to that in 1,000 books of encyclopedia size. If humans were 'only' 4% different this still amounts to 120 million base pairs, equivalent to approximately 12 million words, or 40large books of information. This is surely an impossible barrier for mutations (random changes) to cross, wouldn't that be a reasonable assumption?
  9. Oct 26, 2009 #8


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    Think of it the way you would compare computer programs.

    If you wanted to determine if two computer programs branched off from the same program (which you don't have the source code to) how would you go about it?

    A bit for bit comparison would not tell you much.
    Last edited: Oct 26, 2009
  10. Oct 27, 2009 #9
    Well a genetic "word" would be much longer than 10 bases. Most changes would be a letter here and there... although a gene duplication event would be copying a "word".

    Also, when you dismiss the introns and only compare the exons or coding regions of the genomes between chimps and humans, the similarity is much more impressive with around only a 0.7% or so difference. So it is likely that the phenotypical differences we see between chimps and humans has more to do with how the genes are expressed in development than it does an actual difference in the "words" themselves.

    Genetic comparisons generally tell us how recently related species diverged from a common ancestor.
  11. Oct 27, 2009 #10


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    You might be interested in reading this paper:

  12. Oct 27, 2009 #11
  13. Oct 28, 2009 #12


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    The percent similarity between two species' DNA is not a very effective mehod of comparing similarities on a whole. Our DNA is somwehere around 98% similar to a Chimpanzee, but it is also around 70% similar to a slug, and 50% to a banana (from what I've read on the interweb anyway).

    That being said, it is most important to understand that Chimps are not our ancestors; instead we probably share a common ancestor and the Chimpanzee followed a different evolutionary path. They are more like a "sibling" than a "father" to our species.
  14. Oct 31, 2009 #13


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    I'm glad you like it.
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