Tomorrow Happens by David Brin, Deb Geisler, James Burns Page A
Tags: Fiction, Science-Fiction, Science Fiction - General, Fiction - Science Fiction, Science Fiction - Short Stories
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News, though it offers cold comfort to those still languishing in poverty.
Suppose, through a mix of compassion, creativity and good luck, we complete the difficult transition and manage to spread this happy situation to everyone across the globe, solving countless near-term crises along the way. Will future generations take a full life span as much for granted as modern Americans do?
Of course they will . . . and complain there's nothing natural about an eighty- or ninety-year time limit on the adventure and enjoyment of life.
Already, many proposed methods of life-extension have come up for discussion:
Lifestyle adjustment
Intervention and Repair
Genetic Solutions
Waiting for better times
Transcendence
The first of these, lifestyle adjustment , would seem to offer surefire immediate rewards. After all, most of the increase in average lifespan we've seen in recent centuries came from nothing more complicated than proper diet and hygiene.
But that statistical boost is deceptive! It was achieved by increasing the fraction of babies who make it all the way to the borderlands of vigorous old age. This had little to do with pushing back the boundary itself; the realm that we call "elderly" still hovers somewhere near the biblical three score and ten.
Do all animal species have built-in expiration timers? Some fish and reptiles may not, but most creatures—and especially mammals—do seem to have an inner clock that triggers every individual's decline to frailty after the middle years of fight-flight-and-reproduction run their course.
Mice and elephants lead very different lives—one slow and ponderous, the other manic and fleeting—yet rodents and pachyderms share the same pervasive pattern of aging. Individuals who survive the perils of daily life, from disease to predators, inevitably begin declining after they go through about half a billion heartbeats. (Elephants live much longer than mice, but their hearts also beat far slower, so the total allotment stays about the same.)
The same holds true across nearly all mammalian species. Few live to celebrate their billionth pulse. No one knows quite what this coincidence signifies. Moreover, the program isn't quite rigid. In laboratories around the world, researchers have lately discovered exciting ways to slow the senescence timer—at least in mice and fruit flies—largely by keeping the test creatures hungry . By giving them nutritious but restricted diets, or by delaying sexual reproduction, researchers report in some cases doubling the usual lifespan.
As you might expect, quite a few human enthusiasts are now eagerly applying these lessons from the lab, limiting the calories they eat or forbearing sex, hoping to extend their own lifespans through judicious abstinence. Alas, the results achieved so far—such as a slight reduction in heart disease—have been disappointingly slim.
After a little reflection, this should come as no surprise. Across history, many civilizations have fostered ascetic movements, sometimes in large colonies where dedicated individuals lived spartan, abstemious lives. After four millennia of these experiments, wouldn't we have noticed by now if swarms of spry, 200-year old monks were capering across the countryside?
There may be a good reason why simple life-style changes work in animals, but not us.
Remember that billion heartbeat limit that seems to confine all mammals, from shrews to giraffes? It's a pretty neat correlation, until you ponder the chief exception.
Us .
Most mammals our size and weight are already fading away by age twenty or so, when humans are just hitting their stride. By eighty, we've had about three billion heartbeats! That's quite a bonus.
How did we get so lucky?
Biologists figure that our evolving ancestors needed drastically extended lifespans, because humans came to rely on learning rather than instinct to create sophisticated, tool-using societies. That meant children needed a long time to
Suppose, through a mix of compassion, creativity and good luck, we complete the difficult transition and manage to spread this happy situation to everyone across the globe, solving countless near-term crises along the way. Will future generations take a full life span as much for granted as modern Americans do?
Of course they will . . . and complain there's nothing natural about an eighty- or ninety-year time limit on the adventure and enjoyment of life.
Already, many proposed methods of life-extension have come up for discussion:
Lifestyle adjustment
Intervention and Repair
Genetic Solutions
Waiting for better times
Transcendence
The first of these, lifestyle adjustment , would seem to offer surefire immediate rewards. After all, most of the increase in average lifespan we've seen in recent centuries came from nothing more complicated than proper diet and hygiene.
But that statistical boost is deceptive! It was achieved by increasing the fraction of babies who make it all the way to the borderlands of vigorous old age. This had little to do with pushing back the boundary itself; the realm that we call "elderly" still hovers somewhere near the biblical three score and ten.
Do all animal species have built-in expiration timers? Some fish and reptiles may not, but most creatures—and especially mammals—do seem to have an inner clock that triggers every individual's decline to frailty after the middle years of fight-flight-and-reproduction run their course.
Mice and elephants lead very different lives—one slow and ponderous, the other manic and fleeting—yet rodents and pachyderms share the same pervasive pattern of aging. Individuals who survive the perils of daily life, from disease to predators, inevitably begin declining after they go through about half a billion heartbeats. (Elephants live much longer than mice, but their hearts also beat far slower, so the total allotment stays about the same.)
The same holds true across nearly all mammalian species. Few live to celebrate their billionth pulse. No one knows quite what this coincidence signifies. Moreover, the program isn't quite rigid. In laboratories around the world, researchers have lately discovered exciting ways to slow the senescence timer—at least in mice and fruit flies—largely by keeping the test creatures hungry . By giving them nutritious but restricted diets, or by delaying sexual reproduction, researchers report in some cases doubling the usual lifespan.
As you might expect, quite a few human enthusiasts are now eagerly applying these lessons from the lab, limiting the calories they eat or forbearing sex, hoping to extend their own lifespans through judicious abstinence. Alas, the results achieved so far—such as a slight reduction in heart disease—have been disappointingly slim.
After a little reflection, this should come as no surprise. Across history, many civilizations have fostered ascetic movements, sometimes in large colonies where dedicated individuals lived spartan, abstemious lives. After four millennia of these experiments, wouldn't we have noticed by now if swarms of spry, 200-year old monks were capering across the countryside?
There may be a good reason why simple life-style changes work in animals, but not us.
Remember that billion heartbeat limit that seems to confine all mammals, from shrews to giraffes? It's a pretty neat correlation, until you ponder the chief exception.
Us .
Most mammals our size and weight are already fading away by age twenty or so, when humans are just hitting their stride. By eighty, we've had about three billion heartbeats! That's quite a bonus.
How did we get so lucky?
Biologists figure that our evolving ancestors needed drastically extended lifespans, because humans came to rely on learning rather than instinct to create sophisticated, tool-using societies. That meant children needed a long time to
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