This post is based on my current read, Long for this World, a book by science writer Jonathan Wiener.
Life expectancy is the average number of years a person born in a given time and place can expect to live. The soldiers who built roads across the Roman Empire had life expectancies of about 25 years. By the Middle Ages, life expectancy was at 30 years. The renaissance bumped it up to 33. By the Mid 1700s, people who survived childhood could expect to live about 40 years. By 1900, our great-great-grandparents had an average of 47 years. All the figures above were greatly influenced by high childhood mortality, but we can see how life expectancy has crept up over the centuries.
But what about the last few decades? The following graph represents the increase in US life expectancy since 1960 *.
*data was collected by The World Bank. Follow this link to see how other countries have changed since 1960. http://data.worldbank.org/indicator/SP.DYN.LE00.IN/countries?cid=GPD_10&display=default
With increases in technology and quality of life, similar increases are happening all over the world. Scientists believe our life expectancies increase by two years every decade. That’s an increase of five hours every day. Just think, for every day you live, you receive time your ancestors didn’t have. Wiener writes, “It’s as if we are driving down a highway that is still being built and the road builders are adding to it at a good rate. “
Now the question is: Will we ever run out of road?