if a person 'x' s longivity calculated as 80 years, he is living in japan(for example) I heard it that in japan the longivity is near about 80 years which is the highest in the world, so can general science give the answer that gurantedly how any person can live upto 100 years. This is looking in this world of speed,rush,tensions, few lucky people can only cross the 100 years of their life. Are we fully aware about our systems in the body like endocryne system,limphatic system, neurological system, respiratory system. Is today's science is capable to grow the longivity of the human being.

I was recently reading some reports about global population aging projections ...
and a couple of them made mention of an expected increase in average lifespans in most countries (accompanied with a growing percentage of centenarians) ... and that, allowing for improvements in living conditions and health supports, human life expectancy should continue to increase though at a slower rate than has occurred in the 20th century ...
none of the reports went as far as predicting an upper limit to future life expectancy...

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I think science can give some broad understanding of longevity across a population. Such things as diet, health care, and genetics have a big role. It is harder for an individual. Certainly, there are things we know will decrease life span - bad diet, smoking, high blood pressure, family history of diseases such as heart disease or cancer. But even then, there are individuals that you would predict would have a short life and do not. There is a lot we don't understand.

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At night the stars put on a show for free (Carole King)

One Earth, One Sky - IYA 2009
All moderation in purple

Many people have expected life improvments in life expectancy to decrease, however, in many developed countries they have continued at a fairly steady rate depite many people expecting improvments to slow. One reason why people are living longer could be improved social conditions for the aged. I think in the past many old people were lonely and perhaps saw themselves as a burden to others and so more or less gave up and died, often by restricting their food and water intake. But now many have friends and enjoyable activities they are less inclined to decide it's time to go. I think it would be interesting to see if instituting old age pensions that make the aged financially independant from their families improves life expectancy by making old people stop thinking they are a burden to their families, but that would be a difficult study to do.

The global warming is just supporting the growth of population all over the world!!. it is normally know everyone that in the icy part of the world the population is just thin as compare to the other parts in the world.

The population explosion already came into existence on a large scale "post world war", before world war there were different situation about population in this world, may be the countries were in such a though that to give a cheers for growing population, even the population control program has not repened the good fruits.

There is a sudden growth in population can be seen in asia,europe,america, australia etc, where the population was in control upto 1970.

Later changes takes place when the people changed their awareness about controlling the population. The big population=least facilities=least resources=least output=great expenses on imports=great debts=economic imabalance=high inflation=poverty problem=food problem=rise in all expenses=no profit. This is the normal formula of the impacts when the population rise. But in last 25 years people are getting much better medical facilities, getting really good advise on their health problems. But the above answer is yet to receive. Economics is a social science.

Sunil

Sunil,
I'm sorry, I didn't quite follow your last post.

I am unconvinced that global warming will support population growth. It is possible that warmer climates and higher CO2 will help plant growth. But changing weather patterns (including droughts), increased storms, and the spread of tropical diseases into temperate zones may counteract all that. It is too complicated to know at this time.

As far as populations being in control up to 1970, I would like to see some evidence of that, because I don't think it is true. I remember as a child in the 1960s that people expressed concerns about population growth. I think what we have seen as an acceleration in the last few decades, particularly outside of the US and Europe, is because of the nature of population (exponential) growth.

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At night the stars put on a show for free (Carole King)

One Earth, One Sky - IYA 2009
All moderation in purple

Like rice, beans, corn...

I think Sunil is talking about the expansion of agricultural frontiers, which is thought to be a result of global warming. Inuits planting corn, Siberians growing rice, Greenlanders raising cattle, fish processing in Antarctica Peninsula...

Of course it is all an open question, since we don´t know about the future hydric regime in warmed up places, the impact of diseases and of the extinction of ecological niches and so on...

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What brings us together is stronger than what pulls us apart

Sure, but as much bad stuff might happen as good. Maybe prevailing winds change and various current agricultural regions don't get enough rain any more. Maybe insect species that currently only live in the tropics move into temperate zones and eat all that corn.

And even if it is warm enough in the Artic to grow corn, it doesn't mean the soil is right and that the Inuit are going to instantly know or want to do it.

I also didn't understand what any of this has to do with the OP on longevity.

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At night the stars put on a show for free (Carole King)

One Earth, One Sky - IYA 2009
All moderation in purple

Overall, Sunil, global warming will not help population growth; it will add to greater population concentrations as environmental refugees increase worldwide ... you may have heard about the recent loss of a once-inhabited island in the Indian Sunderbans? The disappearance of Lochara has displaced ten thousand people ... more islands are expected to be lost as the seas continue to rise.

The post WWII period (1950-1970) was not known as a time of population control - in fact, it was the time of the highest birthrate in known history - the generation(s) have since been called "baby boomers" ... and this period contributed to a doubling of the world's population (from 3 billion to 6 billion) in only 41 years. The current population growth is expected to increase by half (from 6 billion to 9 billion) in 43 years.

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There are studies into what causes aging. A lot is biochemical, looking at what drives our bodies to "get old", what causes tissues to stop being youthful, what causes hormones to change their balances, and what could be the effects of preventing those changes. One fascinating discovery has to do with telomeres - end points on chromosomes that determine the number of times the cells can divide. One of the problems with cloned animals is the reduced number of telomeres they begin with.

No, we do not have full answers on how to extend longevity. We also do not know how to make the quality of life and extent of youthfulness extend. But we are studying the processes. In the mean time we have to settle for trying to be as healthy as we can with what we have.

Oh, so *that's* where the problem lies with clones ... I was wondering.

Telomeres may be linked to cancer prevention too - raise the number and you get runaway growth; lower it and you get premature aging. I am somewhat skeptical about our chances of improving something that has been fine-tuned over a long time...

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"We do not require reality to conform to the expectations of the ignorant"

Another major problem (some consider it the largest issue) is that methylation of DNA plays an important role in the regulation of gene expression during embryonic development. At least in the mouse (and most likely other mammals), widespread genome demethylation occurs soon after fertilization, followed by de novo methylation as soon as differentiation occurs. Using somatic nuclear material (already methylated) during the embryo formation process of cloning disrupts this normal process and is thought to contribute to the abnormal development of the clone. Such "epigenetic" problems can result in adult animals with genes that no longer function properly. Some epigenetic defects can even be passed on to subsequent generations but most are expected to be "corrected" by a round of normal egg/fertilization/embryo formation.

Thanks, BioSci, for more insight. Are you suggesting this could potentially be different enough to warrant closer scrutiny/demarkation of cloned animals?

AstroSmurf, I don't think telomeres affect cell growth/reproduction rates, merely the number of times they can successfully cycle. I believe the cancerous runaway growth is caused differently.

No, the potential for genetic problems to persist in the progeny of a cloned or transgenic organism is of biological interest - but not of a concern for safe use of the organism or products derived therefrom. Any cloned animals will have been tested, inspected, and tested again before any products are offered for marketing. The fear of using cloned or transgenic animals (or plants) is simply not founded on any real biological or genetic basis to begin with. It is completely based on fear of something "new" and "what if...?"
Unfortunately, when asked a question about whether the risk of some strange outcome is zero - any scientific answer gets turned into "a real risk exists..." by those that fear genetics.


Additionaly, it is well known that genetic "anomalies" already occur with a significant frequency in all biological populations (mutations, anyone?) - but we do not fret about it because we have learned that it is not a significant concern.
If a mutation or genetic problem is severe enough to be noticed - the cloned animal would be removed from further development.
(animals with "natural" mutations either die or are eaten anyway!)

They'll either adapt or face extinction. Its not that hard a choice. The world they've known is coming to an end, they can end with it or find a place in the one that replaces it.

Something complicated about that?

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The last time I felt a warm fuzzy feeling, I was informed by my doctor that it was just gas.

Well, yes, it is quite complicated, actually.

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"I'm as accurate as any psychic. And I'm a cartoon!" -- Squidward

"Arrrgh, the laws of physics be a harsh mistress!" -- Bender

the cloned item has also the specific longivity period, may be it is too short or may it is too long the clone survives!!

If you lived down here in Florida, you'd see from the newspaper obits that living past 100 isn't all that rare!!!! We just lost one of the last Spanish-American War vets down here at the age of 119!



Seriously, I've seen articles from some researchers (no, can't site them at the moment; if I can I'll look 'em up later) that there is no good reason that the human body can't live for several centuries if we can get a few of the major causes of death like prostate and other cancers under control.

Uh, there is that minor thing about aging to decrepitude.