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Anuraag Reddy

AIESEC India

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Why evolution could never solve aging?

Maybe aging is an essential mechanism to clear out the old and make way for the new like cells within a body?

Maybe every form of life is already close to the upper limit of life expectancy?

Maybe aging is in the nature of carbon based life and metabolism?

Maybe we genetically sacrifice our longevity to survive the stresses of competition.

Emerging Questions:
Is it that our metabolic processes are over-compensated for dominance in their sexual prime which prove detrimental for longevity?

Is it that genes leading to different lifespans are mixed indefinitely in nature that it was never possible to select for it?

Isn't an organism with a longer span of mating at an advantage?

My hypothesis:
In the absence of change in ones environment, or competitive stresses an organism would eventually adapt itself to survive longer.

If every organism is a product of evolution then there must of course be underlying mechanisms within itself to aid such an adaptive process.

Under the influence of adaptive pressure, it would encourage mutation or variations in order create successful variations and also increase the number of life-cycles and so reducing the lifespan.

Under the influence of competitive stress, the dominance would lead to reproductive success and not the span of mating during ones lifespan.

In the absence of change in ones environment leading to adaptive pressure, or competitive stresses from rivals to prove dominance. Species would evolve longer lifespans.

Just a Theory though! But it would predict that

Lifespans of living fossils which have undergone little change in time should be greater than their relatives which have recently evolved.

Life having evolved on geographically isolated places far from intense competitive pressures should have greater lifespans.

Living things higher up in the food-chain or with few natural enemies should have greater lifespans.

Life span in pair bonding species should be higher than tournament species.

Topics: aging evolution
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    Nov 17 2011: My guess about this is that every organism's life is as short as its genes can afford.

    Humans live longer than chimps after menopause, since babies require grandparents as well as parents. (Menopause is 3 years before death in chimps = you die knowing that the last child has been carried to autonomy... Menopause is about 20 years before death in humans = you die knowing that the last child's child has been babysat)
    Longevity has a cost, you know, for the genes. The shorter the life the better. Why is that?

    Well, having offspring means that your genes are now competing for food and sex, and one can understand how the genes would benefit from the non-reproducing organism to be dead. I read of some fish that ages immediately after reproduction, an hormonal booby trap.
    Remember that your genes are in all your relatives, unequally distributed of course. But cousins, siblings and children share your genes and if you can't provide their survival into the next generation, let them take care of it. If there's nothing you can do to help anymore, then get out of the picture ; more of everything for everyone.

    Makes me think about our old people. Once our kids have been babysat by our parents, the best thing they can do to help is to die, isn't it?

    So what lives forever is not subject to natural selection, since no replicator has any advantage of lingering once it's made a copy of itself. Especially if such replacing produces variation that might be beneficial.

    Until recently, no form of life has emerged from something else than natural/sexual selection, so immortal living organisms cannot have evolved.
    In fact, immortal living organisms can only be created by ... I hate to say this... intelligent design!
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      Nov 18 2011: Isn't an organism with a longer life and a longer sexual prime at an advantage? Or maybe breeding after a certain age would mean passing on damaged genes which would prove detrimental on the long run?
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        Nov 18 2011: It works this way if there are no or few factors which introduce evolutionary pressure. Why do turtles live so long? They have hardly any enemies so the longer their lifespan the more offspring they can produce - selection for longevity.
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        Nov 18 2011: - Isn't an organism with a longer life and a longer sexual prime at an advantage?

        I suppose it has something to do with sexual prime overlap. I your prime lasts ages, then it will largly overlap with your children's prime. So children whose parents leave the scene are likely to reproduce more since there is less competition, and thus the genes encoding this trait are selected.

        But there are more possible explanations, depending on the species. One of these might have to do with the number of offspring. Sometimes it may be an advantage to have few offspring and thus have more energy available to ensure their safety. Other organisms such as trees have tremendously long sexual primes and produces hudge quantities of seeds, because of the low cost of offspring in the vegetal kingdom. Thus, yeah, trees would benefit from near immortality and near infinite procreation, in this sense.
        But one thing about trees, though : two generations are never rivals over sunlight or minerals, since
        a seed that has fallen at the base of it's shadowing parent is just about doomed. So a succesful descendant is one that has landed far away, and it can only grow where it's not bothering its procreator.

        All this is just deduction, not proper scientific information, so someone who knows the first thing about biology might rake me over the coals.
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      Nov 18 2011: Does that mean my kids are being kind to me by not having kids yet?
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        Nov 18 2011: Perhaps they need their mother a little longer before she turns her attention to grandchildren (since concentration of energy on grandkids is a hell of a lot more fruitful at this point, evolutionnary speaking of course).

        Or perhaps there's no lady out there as great as mom...
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          Nov 19 2011: Gerald, for a hairless creature you are very sweet.

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