OK, so for some reason my silly little list of founding fathers' ages is getting legs, so OF COURSE this shows up. Education time.
Humans have ALWAYS lived to be between 60 and 80 years old (some MUCH older), assuming they could survive childhood. psychologytoday.com/blog/the-scien…
To wit, here are some more ages in 1776:
Stephen Hopkins, 69
Benjamin Franklin, 70
Samuel Whittemore, 81
More here: allthingsliberty.com/2013/08/ages-o… (also the source of the original info)
Stephen Hopkins, 69
Benjamin Franklin, 70
Samuel Whittemore, 81
More here: allthingsliberty.com/2013/08/ages-o… (also the source of the original info)
The whole "life expectancy" thing comes from two huge driving factors, and several smaller ones.
The first, of course, is infant mortality (colloquially, infant and child mortality is easier to understand). A HUGE percentage of kids died before their first birthday, and many before their fifth. pbs.org/fmc/timeline/d…
On average, if a huge chunk of people die at age 2, and another chunk lives to age 70, the average life expectancy hovers in the middle, for the same reason that if I get $0 and you get $100 we have, on average, $50. Math works.
But another enormous contributing factor was maternal death, specifically childbirth related deaths. academic.oup.com/ajcn/article/7…
You know why so many 17th- and 18th- and 19th-century farmers had two, three, four wives? Because they died in childbirth. A lot. Like, A LOT a lot.
Once again, if a huge portion of your population lives to age 70, and another massive chunk dies before they turn 30, overall life expectancy is dragged down. Because math.
This is, of course, leaving aside all of the advantages conferred by progress over the last few hundred years—sanitation, water purification, vaccination, antibiotics, etc. etc. etc.
All of these new benefits mean people live longer on average at all ages. But they have particularly strong impacts among the most vulnerable populations, especially infants and children.
Child mortality has plummeted in developed economies in the last 150 years, with a corresponding increase in average life expectancy.
But that doesn't mean people used to be gray-haired and toothless at 40. It means they got to know their grandkids because their grandkids got to live.
Don't believe me? Here's the census data from 1900 through 2000 to prove it. census.gov/dataviz/visual…
Incidentally, this is one reason why an accurate census is so important. Data matters. It tells us who we are, and ensures we aren't substituting mythology for reality.
For example, here's a random page from the 1820 census (New York, Schenectady county). Look at all the people over age 45. Even some of the slaves made it (and you surely won't argue it was due to superior living conditions). 
Here is another page, this one (again, completely randomly) from 1800 Vermont, Windham county. Age categories here are left to right: white males under 10, under 16, under 26, under 45, 45+, repeated for white females.
Look at all those old geezers! 14 people over age 45! Except they'd survived the rigors of childhood without modern sanitation and medicine, so it wasn't at all unusual.
In 1830, we started getting more disciplined about it, and broke age brackets down into smaller units—5-year brackets under age 20, 10-year brackets for those over, going all the way to 100+.
Why would they do that if no one lived past the age of 50? Answer: They wouldn't.
There is, granted, significant error in some of these older counts. Birth records are frustratingly uncommon. But if an 80-year-old got misreported as 100+, no one would mistake them for 45.
Here, again completely randomly, is a page from the 1830 census of Monroe, in what was then Michigan Territory. There are five men in their 60s, and one woman in her 70s.
In summary, people have ALWAYS lived a good long time, assuming their luck and living circumstances allowed for it. Rich people live longer than poor people, but people didn't develop angina and gout and drop dead at 43.
This has been DeAnna Tweets about Irritating Canards that Bother Genealogists. We now return you to your regular Internet. /FIN
