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Thread: Polar regions

  1. #1 Polar regions 
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    ok, i know this isn't the most interesting topic .. but..i'm curious!
    Temperature is an important abiotic factor that affects the abundance of living organisms!
    the temperature in polar regions is very low which is not good for our metabolic reactions, how can we survive when we go there???
    and what is the difference between the humans who live in antartica and the humans who live in hot regions? do we have different genes or enzymes that allows us to cope with our environment???


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    well i get this idea from this article "Adapting to Climate Extremes" by http://anthro.palomar.edu, it said that in order to survive in the cold region human that have the temperature regulating system could adapted their body in the cold climate by drink alcohol cause it could raised your blood flow to the body and provide a heat for your body in a temporary time. and another thing you could do is cover your body with clothing like coat, set your house with a warmer.

    we all know that every human in this world had adapted with their environtment in order to survive, not just their body structure (who we see differently from african people, asian to western from size of body to color of body and difference of hb level, thats what happen to eskimo who live in polar region, according to the article they said that eskimo consume in their daily life high calorie fatty food in order to raised the basal metabolic rate to produce more heat for their body, and of course a big coat (':wink:')


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    Forum Cosmic Wizard spuriousmonkey's Avatar
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    The human body is the same everywhere. We have some control systems in place to keep it all the same.

    The only thing that is extra in the polar regions is that we dress to the occasion in a different manner. You would regulate your homeostatis by wearing warm cloths. In the tropics you do the same, except that the outfit usually looks a bit different.
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  5. #4  
    Universal Mind John Galt's Avatar
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    Quote Originally Posted by spuriousmonkey
    The human body is the same everywhere.
    Don't you know about noses? Theyare the long and the short of it.
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    A significantly attractive proposal (backed by significant evidence) points to the interbreeding between Neanderthals—indigenous to the northern hemisphere, and well adapted to colder environments--and the recently migrated humans from Africa, which resulted in the scattering of Neanderthal DNA through the genomes of present-day non-Africans.

    Interestingly, this process has been shown to have altered a number of our genetic features: skull structure, energy metabolism (crucial for life at low temperatures), and skin physiology and morphology (equally important as a means to increase the skin’s ability to absorb sunlight, and thereby produce vitamin D).

    In reply to the final question, the answer is simply yes. Many of which (genes) may have been derived directly from Northern Neanderthals.
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  7. #6  
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    What do you mean, Ophiolite?
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    Human adaptation to different climates is always primarily technology. This includes the clothes worn, the heating systems used, the housing, the method of getting food and so on.

    However, it also includes some physiological (genetic) changes. Ophiolite mentioned noses. Long European noses are better for warming cold air before it enters and chills our lungs. Broad, flat African noses allow faster air movement, but do not warm the air. Pale skin is better for weak sunlight to permit vitamin D manufacture, while dark skins protect against ultra violet damage.

    Inuits tend to have smaller, broader stature - good for conserving heat. Some equatorial African tribes are tall and very skinny - better to cool the body. Many other genetic changes for climate adaptation could be listed.

    However, in spite of these genetic changes, human adaptability largely depends on our superb use of technology, and any individual, regardless of whatever climate he/she is adapted to, can with that technology, live in any other climate.
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  9. #8  
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    Looking at those many photos and videos of traditional Eskimos, Inuits, etc living in igloos, standing on packed snow, etc, one wonders where they get the vitamins and other nutrients that the rest of us get from vegetables, which the snow-bound polar peoples obviously can't grow. Their traditional diet had little or no vegetables, no agricultural or dairy products, and was very low in carbohydrates and disgustingly high in proteins and fats.

    The answer is that they get their vitamins from eating raw meat. For example, the high heat for cooking ruins Vitamin C, and a vegetable-less diet would cause scurvy. Fortunately, there's no/few trees where they are, so even though they do some cooking, it works out that they don't need to cook as much as peoples in temperate or tropical climes.

    Also, a person's metabolism increases dramatically and burns all those "extra" calories they consume.

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    Also because they eat the flesh of predators. Herbivores do not need to manufacture certain vitamins, like vitamin C, since they get those materials in their diet. However, meat eaters cannot, and so their bodies are adapted to manufacture vitamin C etc in their own flesh. If you eat beef, you get no vitamin c. If you eat a seal, you get plenty.
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  11. #10  
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    Oh, thanks skeptic. They eat raw meat? Wouldn't they get ill from some kind of bacterial infection? Although, I suppose, only extremophiles would be able to survive under such conditions.. and perhaps they exist in a kind of stasis?
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    Quote Originally Posted by tridimity
    What do you mean, Ophiolite?
    skeptic has nicely explained my meaning.
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  13. #12  
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    Quote Originally Posted by tridimity
    They eat raw meat? Wouldn't they get ill from some kind of bacterial infection?
    Look at all the people who eat sashimi. I also think people quickly develop the life skill of distinguishing the good parts from the bad parts.
    Grief is the price we pay for love. (CM Parkes) Our postillion has been struck by lightning. (Unknown) War is always the choice of the chosen who will not have to fight. (Bono) The years tell much what the days never knew. (RW Emerson) Reality is not always probable, or likely. (JL Borges)
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    The main problem with raw meat is bacteria that multiply in the dead flesh. Living animals have meat that is essentially sterile. This is a result of the animal's immune system killing off pretty much all bacteria (If they do not, they are very sick!).

    When an animal is killed, bacteria colonise the raw meat quite rapidly and begin to multiply. Leave raw meat in a warm place for 24 hours and eat it raw, and you will get sick. It is called food poisoning.

    However, if you eat raw meat soon after the animal is killed, or keep it very cold, the bacteria are not present in sufficient numbers to be a problem. Now apply this logic to the Inuit way of life .....
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    Don't forget the parasites when eating fresh, raw meat...
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    Re parasites in raw meat.

    This is a function of species. We eat beef rare because there are few problem parasites. Pork, however, should be cooked well to kill parasites.

    I suspect that seals, the main meat of the Inuit, do not have problem parasites able to invade humans. Perhaps someone else can comment on this ....
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  17. #16  
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    Parasites and vertebrates have been co-evolving with each other for a very, very long time. The range of parasites that infect vertebrates is quite astounding; many of them have stages in their life cycles that can include humans, even though humans are often not the definitive host. Many stages in the life cycle involve the parasite being consumed.


    Fish tapeworm could be a problem in the Arctic perhaps? Freezing kills them though. As could Echinococcus. Seals have parasites too, such as Giardia. Also, Trichinella from walrus.


    As always though, prepare your food properly and the these sorts of things should only exist at a low level in the population.
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  18. #17  
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    Eskimo diet may be off topic, so in lieu of posting this stuff, here is “Significance of Parasites in Wildlife” (1956), with the subject of Eskimos from the bottom of page 418 to the top of page 423.
    Grief is the price we pay for love. (CM Parkes) Our postillion has been struck by lightning. (Unknown) War is always the choice of the chosen who will not have to fight. (Bono) The years tell much what the days never knew. (RW Emerson) Reality is not always probable, or likely. (JL Borges)
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  19. #18  
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    Also because they eat the flesh of predators. Herbivores do not need to manufacture certain vitamins, like vitamin C, since they get those materials in their diet. However, meat eaters cannot, and so their bodies are adapted to manufacture vitamin C etc in their own flesh. If you eat beef, you get no vitamin c. If you eat a seal, you get plenty.
    Surely any animal would have a certain amount of vitamins in their bodies at any given time, regardless of the source? And if Eskimos were to have gotten enough vitamins from raw meat, surely predators would have been able to do the same and would not have needed to produce their own?
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