Study: Modern Human Population Explosion Began 2,000 Years Ago
Atlanta, Ga. (CBS ATLANTA) — The human population explosion – commonly attributed to the industrial era of the 18th and 19th centuries – actually began nearly 2,000 years ago at a time when society organized enough to allow families to grow and take advantage of economies of scale.
Research led by Aaron Stutz of Emory University finds that the worldwide surge into the billions for humans was actually started around the beginning of the Common Era during the reign of the Roman Empire. The research suggests that the surge was not a product of 18th-19th Century industrialization and public health progress, but instead was the result of family’s abilities to settle and prosper enough to pass onto the next generation.
“The industrial revolution and public health improvements were proximate reasons that more people lived longer,” Stutz says. “If you dig further in the past, however, the data suggest that a critical threshold of political and economic organization set the stage 1,500 to 2,000 years ago, around the start of the Common Era. The resulting political-economic balance was the tipping point for economies of scale: It created a range of opportunities enabling more people to get resources, form successful families, and generate enough capital to transfer to the next generation.”
Published in the Public Library of Science One (PLOS One), the anthropology research takes a closer look at details such as housing and crop-growing shows that humans were able to overcome the cyclical burden caused by a lack of resources or environmental hardships.
“The recent population explosion was systemically determined by long-term, distinctly pre-industrial cultural evolution,” writes Stultz. “Recognizing that complex social resource-extraction networks support ongoing consumption-based investment in family formation and intergenerational resource transfers, it is important to consider how consumption has impacted the human environment and demography—especially as global population has become very large.”
The research suggests that exponential population growth was the 1,500-2,000 year transition point in which the political-economic balance allowed for successful families to be formed, people to find adequate resources and the ability to generate enough capital to pass it along to the next generation of their family.
“It’s mind-boggling,” Stutz says. “The human population has not behaved like any other animal population. We haven’t stayed in any kind of equilibrium with what we would consider a typical ecological niche.”
The Emory research responds to 18th Century English scholar Thomas Robert Malthus’ controversial essay suggesting that population increases were unsustainable, and would be reduced in a cyclical fashion by famine and disease. His Malthusian Catastrophe Theory was issued in 1798, just prior to the global census size hitting one billion people.
But Stutz notes that the human population not been checked by such factors and has instead remained in an “equilibrium” that saw humans reach 2 billion people after only another 120 years, and then a surge to nearly 8 billion in the past 50 years.
“Modern globalizing transitions in technology, susceptibility to infectious disease, information flows and accumulation, and economic complexity were endogenous products of much earlier biocultural evolution of family formation’s embeddedness in larger, hierarchically self-organizing cultural systems, which could potentially support high population elasticity of carrying capacity.”
Stutz cites the Roman Empire for its levels of prosperousness and advances in architecture and engineering as the end of miserable, short human lives.
“The vast majority of people who lived under Roman rule had a life expectancy into their late 20s or early 30s,” Stutz says. “A huge swath of the population was feeding, quite literally, the dynamism that was taking place in terms of economic and political development. Their labor increased the potential for providing more democracy and competition on the smaller scale. That, in turn, led to a more complex, inter-generational dynamic, making it possible to better care for offspring and even transfer resources to them.”