The human population has a lot to look forward to. Thanks to the miracles of science and technology, we are already living longer, healthier lives than just 50 years ago, and it?s only going to get better.

Better if we have the means to take care of ourselves in our old age, that is.

With a mandatory retirement age set at 65 despite increasing life expectancies, however, many are wondering if they will be able to set enough income aside to support themselves for the increasingly lengthy span of time known as ?retirement?.

Mandatory retirement was originally introduced in Britain under the 1908 Pensions Act. Originally the age was 70, but it was later reduced to 65.

Life expectancy, at the time, was about 50.

Today life expectancy stands at about 75 for men and 80 for women in the UK. The retirement age, however, remains 65.

With more and more health breakthroughs, life expectancy is expected to continue to increase. Research has shown that baby girls born in 2002 in France or Japan, the two countries with the highest life expectancy, have a 50/50 chance of living until 100.

In fact, two of the world?s most distinguished gerontologists (people who study the elderly) have made a bet about future life expectancies which could wildly profit their descendants: Professor Steve Austad, of Idaho University, believed children born today will live to be 150 or older.

However, Dr. Jay Olshansky, of Illinois University, believes life expectancy will cap at 130 ? just slightly older than Jeanne Calment, a Frenchwoman who died in 1997 at the mature age of 122.

The two men have each put $150 into a trust fund to mature in 2150. If, at the time, anyone has reached the age of 150, Austad?s descendants get the booty. If not, Olshansky?s heirs collect the pot ? which should, by that time, be around $50 million.

Whoever wins, with such figures it seems any arguments against raising the retirement age are moot. The writing is on the wall for a life of rest and relaxation after the age of 65. Following the same parameters used in 1908, for example, children born today could, theoretically, not retire until they are well over 100.

In other words, future college grads may not be facing 40 years of the 9-5 routine ? they could be facing 80.

In fact, with the discovery of the ?Methuselah? gene ? a strand of DNA that confers healthy old age on men and women, leading to the prospect that drugs could one day be created that extend human life ? it could be even longer.

It is difficult ? to say the least ? to conceive of people working full-time past the age of 100, particularly in blue-collar jobs like construction.