Worlds of David Darling > Children's
Encyclopedia of Science > Could You Ever Live Forever? > Introduction
COULD YOU EVER LIVE FOREVER?
a book in the Could You Ever? series by David Darling
The greatest certainty in life is death. As we grow old, our muscles and
bones weaken, our skin wrinkles, and our eyesight and hearing become less
keen. In time, as with a worn-out car, some important part of our body breaks
down completely. Then we die. But does this have to happen? Are there ways
in which human aging could be slowed or stopped altogether?
| Mother and daughter
Why do living things die? It would seem much better for an animal or plant
if it could grow up and then stay fit and healthy without aging any further.
But this would not be good for the species, the type of animal of plant,
to which the individual belonged.
Death seems to be nature's way of getting rid of creatures that have outlived
their usefulness. For instance, lions that have lived long enough to have
offspring of their own have served their main purpose. They have helped
to ensure the survival of their species. But if lions never died, the world
would be overrun by them. And the same is true of other species. If individual
animals or plants could live forever, the Earth would quickly become overcrowded.
Why does every living thing eventually die? One possible answer is that
the body's defense system breaks down. Instead of destroying only invaders
such as germs, the defense system may attack parts of the body which are
There is another possible answer. Something may go wrong with the chemical
instructions that tell the body how to repair and maintain itself. While
we are young, these instructions are carried out without a mistake. As each
tiny living unit, or cell, in our body dies, it is replaced by an exact
copy. But as we grow older, the chemical instructions may be partly lost
or imperfectly passed on. Some cells are not replaced. Others are replaced
with faulty ones. As a result, we age. Our bodies develop serious problems,
and we die.
Dying for a Cure
If we knew the exact causes of aging and death, then perhaps we could find
ways to counter them. Some causes of death are known. There are accidents.
People are killed, for instance, by drowning or falling off mountains. There
are also many diseases, such as cancer, which can kill people before they
die of old age. Thus, the average human life span could be increased by
making the world safer and by finding cures for deadly diseases.
But even if all these obvious causes of death were removed, human beings
would not live forever. Our bodies eventually wear are. One way to solve
this problem would be to replace the worn parts with new parts made of artificial
materials. A diseased heart, for instance, could be replaced by one built
from plastic and metal.
It would be even better, though, if scientists could discover the basic
causes of aging. They might find out why our bodies start to break down
as we grow old. Then, further research might show how to greatly slow or
stop the aging process.
So, could you ever live forever? Maybe you would not want to live that long.
Or perhaps you would look forward to all that you could see and learn during
a healthy lifetime of hundreds or thousands of years. In the not-too-distant
future, people may have that choice.