Did Solar Eclipses Boost the Economies of Our Ancestors? These Researchers Think So

From stopping wars between ancient civilizations to confirming the theory of general relativity and rocketing Einstein to fame, the hundreds of solar eclipses that have swept over Earth before today have undoubtedly influenced how we live our lives. But recent research suggests these scientific wonders may have also skyrocketed past societies’ wealth.

A new analysis, conducted by Anastasia Litina, an economics professor at the University of Macedonia, and Èric Roca Fernández, an economist at the CERDI Research Institute in France, found that in pre-industrial societies, human curiosity and economic growth seemed to increase following solar eclipses. The researchers surmise that by stimulating curiosity and scientific thinking, solar eclipses may have also increased the economic prosperity of societies past.

Litina and Roca Fernández turned to several anthropological databases that contain information on the societal practices of historical civilizations, including the Ethnographic Atlas, a collection of categorical data gleaned from over 1,200 pre-industrial societies between the 19th and mid-20th centuries. Societies ranged from small hunter-gatherer groups to larger agricultural communities, mostly spanning areas in Africa, native America, and Southeast Asia.

“We wanted to explore data and civilizations in an era where the mechanics of eclipses were not well-understood,” Litina said. Many more developed civilizations, like those in Europe, are deliberately excluded from this database due to their relatively advanced scientific and industrial practices.

Then, referencing the five millennium catalog of total solar eclipses from NASA, the authors cross-referenced eclipse paths of totality with the locations of each society to determine the number of solar eclipses it experienced during its existence. From there, they searched the available data on a given society and assigned indicators of curiosity, knowledge, technological advancements, and economic growth.

To understand the potential influence of eclipses on curiosity and knowledge, Litina and Roca Fernández looked at factors like the presence of a written language, the playing of strategy games like chess or go, and the accuracy of eclipse explanations in folklore. Indicators of technological advancements included the number and complexity of productive tasks in a society, such as pottery making or dairy production, the presence of infrastructure, like roads and bridges, and the use of a monetary system. Economic growth was measured through proxies like population density, settlement patterns, and societal organization.

Critics of anthropological datasets like these argue that categorizing historical data is, by definition, not entirely objective. John Dvorak, a planetary geologist and author of a book on the science history and forgotten lore of solar eclipses, said he takes issue with the “undercurrent in anthropology trying to make these sweeping statements about societies around the world.”

Roca Fernández conceded that data accuracy could be a potential caveat. Measuring curiosity, technological advancements, and economic development through proxies “is an open assumption that we’ve made,” he said. “Perhaps some people do not agree with us. But [the study] was about reading through what is available and thinking, does it approximate something we are interested in?”

“It’s true that there are biases. I guess this is always the case,” Litina added. But with the right controls, “there are some ways one can actually mitigate these biases.”

One such way the authors did this was by sourcing societal information from multiple databases. They also accounted for a society’s terrain and climate, which could influence both eclipse visibility as well as soil fertility and crop production, thus impacting economic prosperity. Finally, they made societies more comparable by looking at their relative changes in scientific advancements or economic growth compared to their baseline.

After curating data and introducing controls, the study authors then ran statistical calculations to simulate whether societies would be more likely to achieve proxies for curiosity, technological advancements, and economic growth if they were exposed to slightly more solar eclipses.

The team generally found positive correlations between solar eclipse frequency and many of their selected proxies, including population size, settlement sophistication, and evidence of intricate thinking. They calculated that a 1 percent increase in solar eclipse frequency increased the probability that a society reached the highest level of population density — stratified in the dataset as >50,000 people — by roughly 75 percent, while more than doubling the probability that a society had a complex settlement pattern. This 1 percent increase also doubled the likelihood of playing strategy games, while nearly tripling the likelihood that a society had an established writing system.

“The correlation is there, it’s strong, and it’s robust across different [datasets],” Litina said.

Dvorak, however, cautioned that correlations do not mean causation. “There’s nothing there about timing” to ensure that the eclipses preceded the chosen societal proxies, Dvorak said. From the correlations, “I can’t tell if it’s a solar eclipse that produced this change in the culture, or if the change in culture happened first.”

In an effort to show cause and effect, Litina and Roca Fernández searched the Wikidata project, a structured database derived from select portions of Wikipedia articles, for people born between 1600 BCE and 1800 CE who had information on birthdate, birthplace, and occupation. Through this query, they found that children who saw an eclipse between the ages of 5 and 15 were more likely to enter a scientific profession compared to those who didn’t. The effects were more pronounced earlier in history but remained significant up until around the 7th century.

Henrike Lange, an art history professor at UC Berkeley studying the interdisciplinary effects of solar eclipses on science, religion, and art, found these Wikidata results reassuring. “I’m not at all surprised that there would be these beautiful correlations with people entering science professions,” she said.

Eclipses may be uniquely positioned to inspire curiosity and growth, as other natural phenomena can be destructive and, adversely, cripple economies. Case in point: When the study authors substituted solar eclipses with earthquakes or volcanic eruptions and reran their calculations, they found no correlations to curiosity, technology, or economic growth.

The mechanics of eclipses are now well understood and their timing is predicted down to the minute, but data shows that they continue to resonate with people today. An analysis of Twitter data on the day of the 2017 solar eclipse showed large increases in words related to awe, humility, and social connection.

“People felt something from [the eclipse] … even in this modern era,” said Sean Goldy, a postdoctoral researcher at Johns Hopkins University who conducted the analysis. “Now how long-lasting [these effects] are, and how impactful, remains to be seen — but I think the ability for [an eclipse] to be awe-inspiring and connecting is still there,” he said. “Being there and actually witnessing it…is so much more powerful than a lot of people might anticipate.”

Lange is hopeful that solar eclipses may still inspire the children of today’s world to pursue scientific careers, who soon could have two totalities under their belt (the next one will be in 2044). “What people witness in their collective environment in childhood can really create those trajectories for future scholarly lives,” she said.

In an entirely different way, solar eclipses are still contributing to present-day economies. In preparation for a massive influx of visitors on April 8, towns within the path of totality are commodifying this year’s eclipse by hosting weekend-long festivals centering around eclipse history, glamping retreats, and tripling the cost of nearby lodging. But a product can only sell if there is sufficient demand, showing clearly how eclipses still impact us today. People will still travel to great lengths, pay exorbitant prices, and risk uncooperative weather for the chance to watch the sun’s atmosphere dance for a few minutes.