Ifloundered across a personal Rubicon this week and got myself a pair of glasses. For the first time in two years, I can see clearly. But I was right to resist the urge to clarify things around me. No, it's not that I don't like what I see, it's something the eye doctor told me. "Ah, long sightedness, it happens as you get older." Older? How old is older? Does that mean the long slide into senility and ecrepitude has begun? And what's next? Hair? Already gone at age 23. Sculpted body? Never had one. The short-term memory has been deteriorating for years. I'm calling my kids by each others' names and then wondering why they laugh at me. I talk to myself as I walk along the street and don't notice the pitying glances of passers-by.

So what's with this ageing thing? I've been surfing the net, reading books and talking to older and wiser friends. Apparently, scientists don't know why our bodies and minds go downhill as we get older. There's no obvious reason for it. It's not as if we have a "best before" date stamped on our behinds next to the "Manufacturers Recommended Retail Price". Cells can live for ever if they keep getting nourishment so there's no reason why we couldn't last just as long. It may be a built-in population control measure to keep us from overrunning the planet but we have so many other ways of doing that. We pollute, develop weapons of mass destruction and eat junk food-all things that self-evidently shorten the human life span.

Elephants, parrots and turtles all live longer than we do and they don't seem to get decrepit decades before they pass into the animal afterlife. Mind you, how can you tell with a turtle? Our most distant ancestors in the evolution theme park are something called cyanobacteria. They live in volcanos, eat sulphur and cyanide and live forever. There are bacterial colonies in western Australia and the Canadian boreal forest that probably date back to the beginning of life, or at least back when Michael Jackson looked normal. Highly paid scientists and researchers have spent years looking at these things through microscopes, not realizing that the little creatures were staring back and giggling madly at the antics of short-lived, balding, sagging, long-sighted louts on the other end of the tube.

Mind you, we've made good use of the elderly over the years. Being able to live to a ripe old age actually helped our species triumph. Apes and the evolutionary dead end known as Neanderthals barely made it out of their twenties, spending all of their time mating or fighting. Across the forest, a group of hairless, weak but brainy geeks called Cro Magnon's were busy discovering fire and sharpening bits of flint so they could kill something and cook it. Cro Magnon's lived to be sixty or more and scientists speculate that their elderly were the repository of wisdom, knowledge and solutions to common problems. Just as the Neanderthal figured out that sabre tooth tigers were not to be trifled with, he died of old age. His species soon followed and a good thing too. Those heavy bone ridges over the eyebrows would look terrible on a television newsreader.

Now in western countries, and increasingly here in the developing world, old people are a burden, an obstacle to the pursuit of happiness and material success. We whack our parents into old folks' homes and come see them on their birthdays. The bond between our children and their grandparents, the same thing that gave the Cro Magnon the edge over their ugly neighbours, is ignored. I met ageing men and women in India who'd been dumped on the steps of hostels or charities so the twenty-somethings could pursue cyber-stardom in America. This is still the exception to the rule, but it's changing, subtly and dangerously. So when you see me shuffle by in ugly slippers, peering over and under my new specs and forgetting your name, remember that I am the future of the species, whatever the evidence to the contrary.