Why do we live longer than other mammals ?

[UM-Bot]

Scientists believe that our slow metabolic rate is the key to explaining our relative longevity.

According to a new study, humans and other primates such as chimpanzees burn calories at a rate that is only half that of other mammals. This fact is believed to explain why we live a lot longer and grow up more slowly.

Read More: http://www.unexplained-mysteries.com/news/260846/why-do-we-live-longer-than-other-mammals

[Lilly]

Actually, bowhead whales are the longest living mammals. They can live up to 200 years.

[Ashyne]

Actually, bowhead whales are the longest living mammals. They can live up to 200 years.

The Bible says the people of old times lived to 1000 years.

[Lilly]

The Bible says the people of old times lived to 1000 years.

The problem with that is we have no idea how ancient people's idea of time was measured. Add that to the fact that the Bible is scripture (not scientific).

[Bendy Demon]

It would seem that if we burn calories at a slower rate then we shouldn't need to eat so often as we are currently being programmed to do.

Also we shouldn't need such a huge amount of daily calories just to stay alive (as we are commonly told)

But I would think nutrition, hygiene and better environments do a great deal too.

[Frank Merton]

When I read that article on why primates live longer (slower metabolism) it struck me that that might explain why calorie deprivation, which slows metabolism, lengthens mouse lifespans but doesn't seem to work with us. We've already evolved it.

[Michelle]

It would seem that if we burn calories at a slower rate then we shouldn't need to eat so often as we are currently being programmed to do.

Also we shouldn't need such a huge amount of daily calories just to stay alive (as we are commonly told)

But I would think nutrition, hygiene and better environments do a great deal too.

Yeah lets just eat less and sit on our butts so we don't burn any of those pesky unnecessary calories they say we need to live healthy productive lives. Who needs people who do those demanding jobs that require massive amounts of physical exertion and have to have a higher caloric intake to maintain the energy level needed to do so. It's a waste of food.

[Bendy Demon]

Yeah lets just eat less and sit on our butts so we don't burn any of those pesky unnecessary calories they say we need to live healthy productive lives. Who needs people who do those demanding jobs that require massive amounts of physical exertion and have to have a higher caloric intake to maintain the energy level needed to do so. It's a waste of food.

No need to get snide with me.

For the average joe who doesn't work in construction or farms, I simply think that 1500 to 2000 calories is excessive. If all you do is, as you put it, sit on ones butt, then one doesn't need 2000 or even 1500 calories.

But yes, you are right, we would do well to eat less and not eat at rigid times OR eat strictly three + meals a day unless it is absolutely needed.

Edited January 16, 2014 by Ryu

[Michelle]

No need to get snide with me.

For the average joe who doesn't work in construction or farms, I simply think that 1500 to 2000 calories is excessive. If all you do is, as you put it, sit on ones butt, then one doesn't need 2000 or even 1500 calories.

But yes, you are right, we would do well to eat less and not eat at rigid times OR eat strictly three + meals a day unless it is absolutely needed.

Honestly, I do think nutritionists should take into consideration everyone is not the same. When I was in the hospital for heart failure they always send a nutritionist in to talk to you about your diet. Most all my life I have been thin, I rarely sit down to a meal and more or less nibble on healthy food...quite the opposite of most people with heart problems. Her recommended diet was almost three times what I would normally eat in a day, even when I was an athlete.

[grendals_bane]

This study seems to ignore the fact that most animals that live in captivity generally have a longer lifespan than in the wild. This is mainly due to a lack of predation, a steady food supply and advanced medical techniques. It is basically the same reason human lifespans are generally increasing as we are able to remove many of the threats that a life in the wild entail.

[moonshadow60]

Elephants, parrots, and some turtles live 100 years or more.

[nec207]

No need to get snide with me.

For the average joe who doesn't work in construction or farms, I simply think that 1500 to 2000 calories is excessive. If all you do is, as you put it, sit on ones butt, then one doesn't need 2000 or even 1500 calories.

But yes, you are right, we would do well to eat less and not eat at rigid times OR eat strictly three + meals a day unless it is absolutely needed.

If you going to sit on your butt all day !! than really you can do with less than 1,000 and still feel not hungry and be healthy.But in order to live long life you have to starve your self go days with out eating and have no meat because of calorie restriction.

Every time you eat your body release free radicals , this is like pollution and over time damages organs and causes cancer.

[Duchess Gummybuns]

WE LIVE LONGER THAN MOST BECAUSE...

We wear pants.

We are so fabulous, that other mammals can't handle our fabulosity, and they die, while saying: "Aaaaahhhh...I....*cough*....regret not wearing*COUGH*...p-pants..."

[pallidin]

[coolguy]

We live longer because we have doctors and medinces and we pretty much stay safe

[Frank Merton]

Take away predation and disease and natural selection will select for longer living. The reason natural selection doesn't normally do that is because there is no point if the animal is virtually certain to die young anyway. Better in such a case to select for rapid maturity and lotsa babies.

[Leonardo]

The researchers are not comparing other mammal species against our natural lifespan, but against our artificial lifespan - brought about by the invention of medicine, various technologies, social changes and fortified foods, not by "reduced calorie intake/expenditure compared to other mammals".

Go back only 4 or 5 hundred years and the lifespan of the average human was more on the order of 40 years or so, and had been that length of time for centuries before that. When placed in a like environment to other mammals, with no technology, natural foods having to be gained from hunting/gathering - or even subsistence farming, no medicine, etc, we would revert to our natural lifespan.

Edited January 17, 2014 by Leonardo

[Frank Merton]

Leonardo your point is obvious enough but I don't see any relevance.

[Leonardo]

Leonardo your point is obvious enough but I don't see any relevance.

The study examined the calorific requirements of various mammalian species, including primates. It concluded that, if we were to build a graph comparing size of organism vs lifespan, primates would be outliers due to their lower calorific requirements.

Which is fine, when considering the natural lifespans of mammalian species.

Which, for humans, appears to be somewhere on the order of 40-50 years, maybe even a little less.

We do not live to 70 - 80 years old because of this lower calorific requirement, and lumping humans in with the other primates seems a bit false anyway, as humans modify the environment within they they live - other primates do not do this.

The study does not appear to take into account that much of our extended lifespan is down to this environmental modification, so it's conclusions are a bit misleading.

Edited January 17, 2014 by Leonardo

[Sunshine Hoosier]

I remember cousin saying something along the lines that mammals have around the same number of heart beats during a lifetime. Seems like it would be hard to test. I think the extreme size differences in mammals would be a big factor in that idea.

[EllJay]

I find it strange that we die at all, unless it is of an disease or accident. We regenerate most things in our body, except severed limbs.

Also I found it strange that the human body isn't bigger than it is. But perhaps the human body needs some million years before we become bigger, like the dinosaurs. That is, if we can manage to survive and not go extinct before that.

[Bendy Demon]

I find it strange that we die at all, unless it is of an disease or accident. We regenerate most things in our body, except severed limbs.

So can most animals yet they all die just the same. All life dies eventually, immortality is a childish fantasy.

We are not special, we are biological beings, our cells can last and replicate for only so long before they too tire and the whole of the entity collapses.

Our bodies are a size that is sustainable for us and are apparently influenced by our environment. As for dinosaurs, I recall reading that most of them were not huge but probably the sizes of hippos, horses and so forth and few were gigantic like the tyrannosaur or brontosaurs.

Go back only 4 or 5 hundred years and the lifespan of the average human was more on the order of 40 years or so, and had been that length of time for centuries before that.

I don't think one needs to go back that far in order to find that the lifespan of people was rather meager. (150 years thereabouts) Much of the short life was due to hygiene issues, cleanliness and nutrition.

Of course food was not as readily available so putting a few calories on the table was a big enough chore and often that was in the form, as I understand it, of potatoes and breads.

[Frank Merton]

Probably we die because the genetic machinery slowly accumulates errors as we repair ourselves and reproduce worn out cells. The fact that the vast majority of animals die before their natural time from predation or accident or disease removes any reason for natural selection to tackle this phenomenon except in the genome, and even here errors happen, often leading to species extinction.

It makes sense if the above is true that slower metabolism would make for longer lives -- less damage and repair and so on. So to live a long life I guess we should look for ways to slow the metabolism. It works out that lack of exercise has the opposite effect -- fit people have slower metabolisms. Other things to do are restrict calories and avoid stress and infections.

[EllJay]

So can most animals yet they all die just the same. All life dies eventually, immortality is a childish fantasy.

We are not special, we are biological beings, our cells can last and replicate for only so long before they too tire and the whole of the entity collapses.

In 1786, average life expectancy was just 24 years. A hundred years later (1886) it doubled to 48. Right now a newborn can expect to live an average of 76 years. With recent discoveries in biology, many scientists predict that life expectancy will continue to triple-digits. In fact, if they are correct, humans shouldn't have to die at all in the future.

...............

telomeres, these molecular chains have often been compared to the blank leaders on film and recording tape. Indeed, telomeres seem to perform a similar function. During the replication process the spiral DNA molecule must split in half and reassemble a copy of itself. Protecting the vital DNA molecule from being copied out of synch, telomeres provide a kind of buffer zone where mis-alignments (which are inevitable) will not result in any of the important DNA code being lost.

Perhaps the best analogy I have heard is to compare the telomeres to the white margin surrounding an important type written document. In this analogy, the printed text is the vital DNA code while the white space is the "blank" telomeres. Imagine that this paper is repeatedly slapped on a copy machine, a copy is made, and then that copy is used to make another copy. Each time the paper is subject to errors of alignment and these errors accumulate. After enough copying, it is probable that the white space will diminish and some of the actual text will not be copied. That's what happens inside our cells and it is the reason we get old and die.

Telomeres -- programmed to die!

Scientists observe that the length of telomere chains becomes shorter as we grow older. Eventually the telomeres become so short that cell replication produces lethal errors or missing pieces in the DNA sequence, ending the cell's ability to replace itself. This point, when the cell has lost vital DNA code and cannot reproduce, is called the Hayflick limit. It's the measure of how many times a cell can copy itself before it dies.

Some cells in our body have a very high hayflick limit. Cells that line the inside of your mouth and intestines, for example, are constantly being worn away and replaced. Indeed these cells appear to have the ability to regrow telomeres even in aged bodies. Scientists were curious why some cells shut down telomere growth with age, and some do not.

Dr. Langmore used physical, biochemical, and genetic techniques to study the structure and function of telomeres. His group developed a cell-free system to reconstitute functional model telomeres using synthetic DNA, and studied the mechanism by which telomeres normally stabilize chromosomes and how shortening of the telomeres could cause instability.

The protein factors responsible for stabilizing the ends of chromosomes are being identified, cloned, and studied. Electron microscopy is used to directly visualize the structure of the model telomeres. Dr. Langmore's group used new enzymatic assays to determine the structure of telomere DNA in normal and abnormal cells grown in vivo and in vitro, in order to address specific hypotheses about the role of telomeres in aging and cancer. It's exciting research, for sure, and there have been some promising discoveries.

Scientists have discovered an important enzyme that can turn the telomere production on the DNA molecule "on" and "off." It's called telomerase.

http://www.viewzone.com/aging.html

Our bodies are a size that is sustainable for us and are apparently influenced by our environment. As for dinosaurs, I recall reading that most of them were not huge but probably the sizes of hippos, horses and so forth and few were gigantic like the tyrannosaur or brontosaurs.

The world has been, and are, sustainable for us to be way bigger then we are, considering we are on the top of the foodchain with our ability to organise, hunt and defend ourselves. Most living organisms in the world are, and were, smaller than us, but the interesting thing is why dinosaurs got as big as they did.