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A tortoise reputedly collected from the Galapagos islands by Charles Darwin has turned 175. What if humans lived that long?
Harriet the giant tortoise has celebrated her 175th birthday and is now probably the world's oldest living creature. Her longevity has been put down to lifestyle and genes, and her keepers at Australia Zoo in Queensland say she could reach 200.
"She's not under any pressure, she goes at her own steady pace, doesn't burn up any energy and is loved by everybody," says a zoo spokesman.
So what if humans lived to 175? At the moment the oldest fully authenticated age to which any human has ever lived is 122 years and 164 days, according to the Guinness Book of Records. French-born Jeanne-Louise Calment put her long life down to keeping active. She took up fencing at 85 and was still riding a bicycle at 100.
But surely at 175, a person would be unable to do very much physically. Not according to some scientists.
Age limits are going up
At some point in the future, as medicine becomes more and more powerful, people will inevitably be able to address ageing just as effectively as they address many other diseases, says Cambridge University geneticist Aubrey de Grey.
As a result none of our old age would be lived in frailty, debility and dependence. People would be youthful, both physically and mentally, right up to the end, he says.
Youthful in old age
Living a longer, healthier life will have major social implications. The traditional course through life could be replaced with something new. Instead of education, work, then retirement, it might become normal for 70-year olds to go back to school and for 80-year-olds to start new careers.
It is argued that scientific advances in anti-ageing treatments means living longer will not place a burden on health care, because it will increase people's health span and not just add some extra years in a care home with little quality of life.
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But while people might be old and fit, independent living might not be possible. Research has already shown that people living longer is already resulting in the family home filling up.
With retired people struggling by on an average income of about £11,000, more and more are going to live with their children because rising health, heating and council tax costs make it harder for them to keep their homes.
Young people priced out of the housing market are also staying at home. Living with many generations in one house might make those 175 years go very slowly.
The state and companies will also feel the pinch, paying out pensions for much longer.
The impact on the Earth's natural resources will also be affected. But some argue that longer life expectancy could make people take more of a personal stake in the future, leading to more responsible and sustainable policies. Only time will tell.
Add your comments on this story, using the form below.
According to Genesis ch 5, Methuselah lived to the ripe old age of 969!
Tim Sherwin, Derby
As impressive as it is for a person to live 120+ years, surely its got to be a bit depressing to think that you've been a pensioner for half your life. It could be interesting in the nursing home with potentially 3 family generations present at once though.
Stewart, Bracknell, UK
I think it would be very sad to see people living for so long. Having seen the grief it causes to people to see their generation die and to have few, if any, original friends and relatives left, some people living to the age of 175 would turn their last 100 years in 100 years of emotional solitude.
Davoc Bradley, Leeds
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