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Medical Question about brain development.

  1. Mar 5, 2007 #1
    without our brainpower we would be close to the bottom of the food chain... am i right?

    a human is slow compared to most mammals,
    a human is weaker then all predators around our size.
    a human has bad vision, hearing and smell sense compared to the rest of the
    earth creatures. (special cases not counted)
    humans no longer have the "fur" to live naked in northern countries during winter.

    so basically without our brains advantage over the rest of the animal kingdom we would be toast.

    my question is this.
    is the development of the brain controlled by us and our will to explore and improve. is it our wants and desires that get programmed into our genes and passed on to our kids?
    say if someone with 120 and 110 iq have wanted to be smarter their entire life. then they get a child.
    as an adult... would that offspring have a better chance for more mental capacity then children of 120 & 110 iq parents that are happy with they iq and never gave it another though?.

    for the sake of objectivity.
    lets say these 2 children would be placed in identical foster homes and had no contact with their original parents.
  2. jcsd
  3. Mar 5, 2007 #2
    Even without the brains, humans do have some distinct advantages.

    Our day vision is actually really good compared to many creatures. It's only in special cases, like eagles, that we lose the vision contest. We do suck at smell. Our hearing is a bit in-between, but we have pretty good differentiation (i.e. our range of audible frequencies isn't spectacular but we can differentiate within the range fairly well).

    We don't have the fur, but we've been able to start fires and wear animal skins for evolutionary amounts of time. Certain breeds of beaver would be in trouble without their dams too. If we take our brain down, we would at least have to keep our warming behaviours, would you consider that fair?

    A human is also great in heat. We can work in hot weather. This is an advantage in an African savanna when you are hunting a gazelle. It will run away, and you can't possibly outrun it, but eventually it will fall over from heat exhaustion, and a human can track it. Wolves use a similar strategy, tracking by smell. Humans track by vision and, yes, big brains to infer where the prey may have gone. You can't just take brains out of the equation wholesale -- just as you can't remove an owl's wings (change them to extra legs, maybe) or a wolf's nose and ask how they could survive in the wilderness without their one minor advantage. But that doesn't negate the fact that we operate better endurance-wise than just about anything when working hard at noon on a summer day in the savannah.

    As for your actual question, that covers wide ground. The short answer is no. However, it could be that somebody who wants smarter kids has genes that make that person more likely to want the future to be better, and so their offspring might have the same "pure nature" element of their intelligence but is more likely to strive to improve himself, thus giving him an advantage in the "nurture" element.* Such a person may also be more likely to choose a smart mate, improving the odds. I'm sure other scenarios could be constructed. But there is no real reason to believe that just because we very much want something to be so, that it becomes so. One simple way to think about it is how would your body even know how to recode DNA in order to make the kids smarter?

    It's incredibly hard to say, because how much of intelligence is nature, and how much nurture, and how much is somehow in-between (I leave how that works to your imagination), is very much an unknown today.

    *it could also work the other way. The parent has "110-120 IQ" (ignoring the problems with whether IQ measurement is really an indicator of how smart you are) precisely because they worked hard and strived for it, while the happy guy is just smart naturally, damn him. So possibly the happy guy could end up with a motivated kid that far supercedes him while the parent with hope for the future has a kid who can't possibly work any harder than his father and has the same nature element, so he cannot surpass his father.

    All people mentioned are assumed to be males for grammatical convenience.
    Last edited: Mar 5, 2007
  4. Mar 6, 2007 #3
    thanks for the reply, im thinking that you're right.
    we cant possible know at this time... bugs me to no end.
  5. Mar 6, 2007 #4

    jim mcnamara

    User Avatar

    Staff: Mentor

    FWIW - everyone focuses on the traits of individual humans. However. Humans changed their position in the world ecosystem (from lion chow to overpopulation) because of social interactions and the effectiveness of groups. Not because of spectacular acheivements of one person with special gifts, like we want to think might be the case.

    We are more like ants than you imagine. We derive most of our ecological domination from working in larger groups. Culture is almost everything, and is what is currently responding rapidly to selection pressure, because culture doesn't have a 20 year generation time. Note: I'm not saying that all cultural changes are good or bad or even have value. Just that the rate of change is phenomenal.

    Example: The change in culture that a town dweller living in 1200 AD saw during a lifetime is equal to the amount of cultural change we see by reading the Sunday New York Times this week, and comparing it to last week's edition.

  6. Mar 7, 2007 #5
    Well Said. If we all had to design and build our own cars, there would be a lot more pedestrians.
  7. Mar 8, 2007 #6
    Or a lot less and very sticky pavements. Could be the solution to UK traffic conjestion. I'll build a tank

    At various points in an animals evolution there are key decision points. it is often useful to look at the Octopus as a comparison to Humans. (I know you think this is weird).

    But the octopus and the others in it's family should have a hard shell which makes it slow but quite succesfull, but it lost the shell and became a fast hunter with a bigger food source but also needed a bigger brain to stay alive without the inbuilt protection system.

    Humans according to the last theory I heard were in an environment undergoing change. they could have stayed in the trees and been quite successful, but some headed out into the plains where there was not the competition for food, but they needed bigger brains to survive out there, luckily it seems that the higher meat content they scavenged out on the plains enabled that brain development.
  8. Mar 9, 2007 #7
    so the next step is space, we will be needing bigger brains there aswell.
  9. Mar 9, 2007 #8
  10. Apr 23, 2007 #9
    so basically what you are saying is that our race is doomed. ok.

    if it is always limited to the dumber parent then the world will grow dumber and dumber.
    seen the movie "idiocracy"?
    deals with this subject :P

    suffice to say, the world will soon switch from water to gatorade.
    (the plants didnt like it)
  11. Apr 23, 2007 #10
    it depends on how you view the whole nature vs nurture debate. If you are more towards the tside of nature than you would find the best mate. However if you are more towards the side of nature...then you will attempt to [1] find the best foods/liquids/vitamins(nutrition) to help your child and eliminate the rest [2] find the best education(probably homeschooling) possible for your child and eliminate all other factors(primarily non-educational tv shows, which is far worse than video games =] IMO). But again it comes down to balance cuz you can't overexert your child mentally or physically but a combination would be best than letting their brain rot...
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