Longevity Throughout History – About

Updated May 11, 2013.

How long did humans live in the past? We often hear statistics about the average lifespan of people living hundreds, even thousands of years ago. Were our ancestors really dying at the age of 30 or 40, back then? To help you understand how life expectancy and life spans have changed over time, heres a little primer on longevity throughout history.

Lifespan vs. Life Expectancy: The term life expectancy means the average lifespan of an entire population, taking into account all mortality figures for that specific group of people. Lifespan, by contrast, is a measure of the actual length of an individuals life. While both terms seem straightforward, a lack of historical artifacts and records have made it tough for researchers to determine how life spans have evolved through history.

Life span of early man: Until fairly recently, little information existed about how long prehistoric people lived. Too few fossilized human remains made it tough for historians to estimate the demographics of any population. Anthropology professors Rachel Caspari and Sang-Hee Lee chose instead to analyze the relative ages of skeletons found in archeological digs in eastern and southern Africa, Europe, and elsewhere. Comparing the proportion of those who died young, with those who died at an older age, the team concluded that longevity only began to significantly increase (that is, past the age of 30 or so) about 30,000 years ago quite late in the span of human evolution.

In an article published in 2011 in Scientific American, Caspari calls the shift the evolution of grandparents, as it marks the first time in human history that three generations might have co-existed.

Life expectancy through to 1500 A.D.: Life expectancy estimates, which describe the population as a whole, also suffer from a lack of reliable evidence gathered from these periods. In a 2010 article published in the Proceedings of the National Academy of Sciences gerontologist and evolutionary biologist Caleb Finch describes average life spans for ancient Greek and Roman times as short: in the area of 20-35 years, though he laments the numbers are based on notoriously unrepresentative graveyard epitaphs and samples.

Moving forward along the historic timeline, Finch lists the challenges of deducing historic life spans and causes of death in this information vacuum. As a kind of research compromise, he and other evolution experts suggest a reasonable comparison can be made with demographic data that does exist from pre-industrial Sweden (mid-18th century) and certain contemporary, small, hunter-gatherer societies in countries like Venezuela and Brazil.

Finch writes that judging by this data, the main cause of death for centuries would most certainly have been infections, whether from infectious diseases or infected wounds from accidents or fighting. Unhygienic living conditions, with little access to effective medical care, meant life expectancy was likely limited to about 35 years of age. Thats life expectancy at birth, a figure dramatically influenced by infant mortality pegged as high as 30%. It does not mean that the average person living in say, 1200 AD, died at the age of 35. Rather, for every child that died in infancy, another person might have lived to be 70.

Early years up to the age of about 15 continued to be perilous, thanks to risks posed by disease, injuries, and accidents. People surviving this hazardous period of life could well make it into old age.

Other infectious diseases like cholera, tuberculosis and smallpox would go on to limit the longevity of the day, but none on the scale of the bubonic plague of the 14th century. The Black Death moved through Asia and Europe and wiped out as much as a third of Europes population, temporarily shifting life expectancy downward.

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Longevity Throughout History - About