(From Tech Central Station). The history of civilization can in many ways be viewed as the history of increasing longevity. While historical increases in life expectancy occurred for reasons that have little to do with how biotechnology will lead to radical life extension in the future, it is still informative to look at the big picture: "The life expectancy, if I can go back to 1700, was only about 35 years at birth. In 1900, 200 years later, it had increased by about 12 years - it was in the neighborhood of 47 in Western European countries. And, today it's 77 or 78, so in a century we added 30 years to life expectancy, maybe a little bit more. ... Public health reform, cleaning up of the water supply, cleaning up of the milk supply. But if you said what was the single most important factor, it's technological change."