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Questions for Creationists: Human Brain Size

Discussion in 'Origins Theology' started by Notedstrangeperson, Sep 1, 2011.

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  1. juvenissun

    juvenissun Veteran

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    Yeah. The two displays are used for teaching. You do not see things that clear in the field, in particular, if the chimp is higher than a human.

    Fine, we can tell a little difference, may be 10% difference. So what? Can we see the real differences?
     
  2. juvenissun

    juvenissun Veteran

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    OK, I learned. Thanks.

    But, how many these kind of traits are there between ape and human? Are there more than three (A, B, C). So sample#1 has A, sample#2 has A and B, and sample#3 has A, B, and C. And these three samples are transitional between ape and human?

    How about that we need to see trait D in order to call it a human. I don't know what that is, but I can make up (or select) one. In that case, how could you say that I am not right? For example, If one courageous anthropologist insisted that australopithicus IS a human, why is it wrong?
     
  3. shernren

    shernren you are not reading this.

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    Absurd. The moment I see a skeleton, I know at the very least that I am not dealing with an invertebrate, which already cuts out half of all animal life on the planet and many possible lifestyles.

    Defending the word of God is one thing - practically deifying ignorance like this is another.
     
  4. Notedstrangeperson

    Notedstrangeperson Loudmouth

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    That's actually a really good question.

    Humans have many traits which other apes don't have - we walk upright, we have no fur and we have very large brains for our body size. Transitional fossils have some of these traits. The early ones are distinctly more ape-like (with a few human traits) and later ones are distinctly more human-like (with a few ape traits). For example:

    Aripithecus Ramidus
    Human traits: Partly bipedal; small canines
    Ape Traits: Ape-like feet; ape-like hands; fur; heavy brow ridges; sloping forehead
    Brain size: Smaller than a chimpanzee (350)

    Australopithecus
    Human traits: Mostly bipedal; small canines; human-like feet
    Ape traits: Ape-like hands; fur; heavy brow ridges; sloping forehead
    Brain size: Same as a chimpanzee (400)

    Homo Erectus
    Human traits: Completely bipedal; small canines; human-like feet; human-like hands; used tools and fire; no fur
    Ape traits: Heavy brow ridges; sloping forehead
    Brain size: Larger than a chimpanzee but smaller than a human (between 600-1000)

    Homo Sapiens
    Human traits: Completely bipedal; small canines; highly advanced use of tools; no fur; human-like feet; human-like hands
    Ape traits: Some people still have brow ridges (most don't)
    Brain size: Very large (1,250 - 1,600)

    Keep in might though that evolutionists do not believe there was any 'magic moment' where an ape suddenly became human (although theistic evolutionists might disagree ;)).

    If there is one single trait that makes us human is probably our large brains. I think scientists have identified a few genes which greatly increase brain size - perhaps that is "trait D".

    Possibly because it has more ape traits than it has human traits - although I should point out evolutionists haven't agreed on when exactly 'apes' became 'human'.
     
    Last edited: Sep 7, 2011
  5. juvenissun

    juvenissun Veteran

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    I can argue:

    Even so, because it is the first skeleton which shows "a" human trait, then it could be qualified to be called a human. Later discovered skeletons are more and more like human. Fine, then they ALL are humans.

    What's wrong with this argument?

    [because human can "think". --- apes can think too.]
    [because human can think "better" (larger brain). --- Ah ha, now, define "better".]
     
  6. Notedstrangeperson

    Notedstrangeperson Loudmouth

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    Here's an artist's interpretation of the earliest (confirmed) human ancestor, Ardipithecus Ramidus:

    [​IMG]
    There is very little difference between Ardipithecus and a modern chimpanzee - except for one, very important difference. Aripithecus did something so modern ape can do: it walked upright.

    This trait - the beginings of bidepedalism - is what makes it a human ancestor, rather than just an extinct type of ape.

    But aside from that ... well, it's not much more than a chimpanzee. Even it's cranical capacity is smaller (ave. 350cm) than a chimps' (ave. 400cm). If you were to meet one of these animals, would you consider it human?​
     
  7. juvenissun

    juvenissun Veteran

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    Assume the restoration is honest. The artist still can do one more (or less) thing: take off the hairs. Then show it to a toddler to see what he would say.

    More importantly, what else could we know about this creature except how might she move on her body parts? Could there be something critical which is not observable from the skeleton? Did they make arts? or sing simple (?) songs? or eat cooked food? If they are not likely to do that, then go to the next one until we find one which can be recognized to do such things. If so... what would be the species name for that creature?
     
  8. Notedstrangeperson

    Notedstrangeperson Loudmouth

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    Removing it's fur probably wouldn't change our opinions much. After all, we can tell the difference between a human and a bald chimp.

    [​IMG]

    Jambo, the bald male chimp from Twycross zoo, UK

    Other hominids showed signs of becoming human - making fire (homo erectus), painting (archaic homo sapiens), or making musical instruments out of bone (modern homo sapiens) etc. Ardipithecus showed none of these.

    It's brain size - which remember is smaller than a modern chimpanzee's - suggests it didn't have the same intelligence we do.
     
  9. juvenissun

    juvenissun Veteran

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    OK, I will argue by following your idea, the brain size.

    I guess there are other animals that have larger brain (in absolute size) than us. How could we know that elephant is not more intelligent than human just by looking at the size of their skulls?

    Also, would the difference between brain size be proportional to the difference in the degree of intelligence? I guess not. If so, what makes human so disproportionally higher in intelligence? There must be something else than just the brain size. Yes, may be it is the brain structure. But how could we see the brain structure by looking at a skull?
     
  10. KerrMetric

    KerrMetric New Member

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    Try Google.
     
  11. Papias

    Papias Listening to TW4

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    juvi wrote:

    It's unsurprising that scientists have looked at that. Encephalization quotient - Wikipedia, the free encyclopedia

    Papias
     
  12. Notedstrangeperson

    Notedstrangeperson Loudmouth

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    As Papias mentioned, in general the larger the brain is compared to the body, the more intelligence the craeture. Humans have the largest brains in comparison to their size. For the record, anything below 900cc is abnormal for a modern homo sapiens. Judging by brain size - which for the moment is all we have to go on - Ardipithecus was not as intelligent as a human. It only had an avergae brain size of 350cc, smaller even than a chimp.

    Going back to your original question Juvenissun - many extinct apes had traits which, today, are unique to humans because they are not found in other apes. This is how we know they are human ancestors.

    If there is some unique trait that crossed the line between "ape" and "human" it was probably our brain size. You might be interested in homo erectus: their cranial capacity ranged between 600 - 1,000cc. They entered the human range, but only just.
     
  13. chris4243

    chris4243 Advocate of Truth

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    While brain size is important, it's obviously not as simple as bigger brain = better. For one thing, brain size increases with animal size, at least among mammals.* For another, a very small mammal might have a proportionately large but still very small brain. Finally, intelligence does not mean ability to do technology nor does it guarantee the manual dexterity to use any.

    So for example, an eagle excels at graphics processing, image recognition, and three-dimensional navigation. You only have to look at our attempts to have computers see to appreciate how difficult a task those are, but nevertheless we brush it off as unimportant.

    Meanwhile, we humans augment our own limited intelligence by transposing some of our memory and calculations to our environment (ie computers and books), by joining together our minds into a gigantic societal effort (if we see farther than others it is because we're standing on the shoulders of giants, or try going to the moon on your own).

    *us mammals, due to the peculiar feature that we are warm-blooded, must burn a tremendous amount of energy to maintain our temperature. This means that the brain with its massive energy requirements isn't really particularly costly.
     
  14. juvenissun

    juvenissun Veteran

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    My challenge was not answered:

    If bigger brain does not mean more intelligence, that would mean the brain structure of human is special (Is it true? Is human brain better structured than the brain of elephant?) . However, how could we know this from examining a skull (fossil, skeleton) in which the brain is gone? How do we know that the small(?) brain of dinosaurs did not have a super structure and made them much smarter than human?

    If the brain characterize human, then could whatever animal with a brain function faster or more efficient than human brain be called human-like?

    If more intelligent does not mean having technology, then what makes us develop technology? I like to go back to the very simply fact, why is human the only creature who knows how to raise and use fire? May be we should define human by the ability of using fire. Is that a better criteria? Can you see that from skeletons?

    The argument seems chaotic. The focal point is: fossil or skeleton does not tell if the life was human-like or not. It only provides a reference, and we need to see the actual action of the life to decide. Since we can not do that, so it is not meaningful to say a certain ape is more or less human-like just by looking at its skeleton.

    --------

    by the way, are chimps bipedal? I think they are.
    Again, just by seeing the skeletons, how do you know they are not?
     
  15. chris4243

    chris4243 Advocate of Truth

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    The fossils will tell us how similar they were to Homo sapiens. Not all Homo sapiens are human, if by human we mean the mental capabilities needed to be technological.
     
  16. juvenissun

    juvenissun Veteran

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    If so, human is not evolved.
     
  17. chris4243

    chris4243 Advocate of Truth

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    I think it would rather mean that humanness is an emergent property.
     
  18. Notedstrangeperson

    Notedstrangeperson Loudmouth

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    Having a physically larger brain doesn't mean being more intelligent. Having a large brain in comparison to the rest of your body does - known as the encephalization quotient (EQ) or body mass-to-brain-ratio. Humans, in general, have the largest EQ.

    Modern Humans: ave. EQ 6.28
    Common Chimp: ave. EQ 2.38
    (R.D. Martin, 1984)

    Female chimps:
    - Between 2 - 3.5ft tall
    - Weigh between 57-100lbs
    - Average cranical capacity of 400cc.

    (Estimated) female Aripithecus Ramidus:
    - Just under 4ft tall
    - Weighed roughly 110lbs
    - Average cranial capacity of 350cc

    In other words they were about the same size as modern chimps but had a smaller EQ, meaning they were likely just as intelligent than chimps - maybe even less intelligent.

    Basically Aripithecus was a human ancestor, but they were not "humans".

    Unlike extinct hominds, chimps are alive today, so we can see how they walk.

    Chimps can walk on two legs but for only a short amount of time. When a human walks, they put one foot in fron of the other. When chimps try to walk, they swings their legs around from the side, giving them a sort of waddling gait. Their hips, their spines, their femurs, their knees and their feet aren't really supposed to walk upright for a long time, so we can't really call them bipedal.
     
  19. juvenissun

    juvenissun Veteran

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  20. chris4243

    chris4243 Advocate of Truth

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