Storytelling Science

Why your children will live to be two hundred years

Amitabha Mukerjee


 

Legend has it that sages like Vishwamitra or Abraham lived for thousands of years. In Harry Potter and the Sorcerer's Stone, the wizard Nicolas Flamel lives for more than six hundred years because he has the elixir of Life.

Today this stuff of legend has moved into the laboratory, and science seems to be holding out the real possibility of an elixir of immortality.

Around the time of Buddha and Christ, humans were lucky to live till forty, and average lifespan was less than twenty years. By the end of nineteenth century, this had doubled to forty. Death was far more commonplace even in our parent's time. Today the average life expectancy in some cultures has touched eighty years.

In merely two thousand years, we have quadrupled our life-span. All indications are that this trend is accelerating; perhaps in a couple of hundred years, lifespans may double once more.

So far, much of our increased longevity has been fueled by cleaner water and better medicine, but today's improvements owe more to technology such as organ replacement and genetic manipulation.

Pre-Programmed Death

Biology balances the energy needs of an organism with its ability to transmit its genes to the next generation. Once the child generation is ready, parents start to compete over finite energy resources, and it is more efficient for the species as a whole if the parents were to disappear. In many species, the male dies immediately after copulation - some male spiders actually offer themselves to be eaten by the female, and their heads get munched up even as the abdomen continues to inject sperm. In some species like the octopus, the female stops eating and dies immediately after laying eggs. The progeny therefore have unchallenged access to the food resources available.

It seems that all animals (including us) have genes that help ageing, e.g. by blocking mechanisms for cell repair (which costs prodigious amounts of energy). In the tiny worm called C Elegans, one such gene called daf-2 has been identified; mutating it increases the worm's lifespan from 2-3 weeks to more than a month. Similar genes have been found in the rat, and studies on humans are well advanced.

Another factor helping longevity is artificial transplantation. Vajpayee's artificial knee enables a more active lifestyle, keeping him fit. Today, artificial organs are available for most body parts, with the notable exception of the brain. Among the other holdouts, artificial livers that will work until you get a human donor, or artifical lungs from stem cells, are likely to become feasible within years. Even for the brain, transplants are becoming possible, e.g. in experimental treatment of diseases such as Parkinson's disease, where tissue from the top of the spinal cord, or stem cells from an aborted foetus, have been implanted successfully to replace dead brain tissue.

Some serious scientists also believe that within a few decades, we will have artificial machines operating at the level of human functionality in every sphere. A worldwide effort called RoboCup is trying to form a human level world champion soccer team by 2050. The possibility of such efforts succeeding is underlined by the dramatic growth in computational speed - by 2050 they will be a trillion times faster than today's computers. What takes a year of computation today will be possible to do in a millionth of a second.

Eventually, biological transplants may merge with artificial implants, so that humans with 50% artificial parts may be indistinguishable from robots with bio-parts. Indeed, one of them may be your two hundred year old grandchild!

The Ethics of Immortality

But the possibility of extended longevity raises its own questions. A bestselling French novel by Jean-Christophe Rufin describes Globalia, a world-spanning empire where people live for hundreds of years, isolated from hoards of barbarians living in "non-zones" beyond walls of bullet-proof glass. For a technology-poor country like India, such technologies raise the important question: will India become a non-zone in the coming Brave New World?

These are important worries, but there are other aspects as well. Returning again to Harry Potter, we find Nicolas Flamel is about to destroy his elixir of life. Harry is incredulous, and asks his guru, Dumbledore: "But that means he and his wife will die, won't they?"

Dumbledore smiles at the look of amazement on Harry's face: "To one as young as you, I'm sure it seems incredible, but to Nicolas and Perenelle, it really is like going to bed after a very, very long day. . . You know, the Stone was really not such a wonderful thing. As much money and life as you could want! The two things most human beings would choose above all - the trouble is, humans do have a knack of choosing precisely those things that are worst for them."

Whether for good or for worse, our lifespans will go on increasing. Will it marginalize cultures like India? This column seeks your help please start this debate with some children near you to increase awareness of these issues in coming decades.