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A paper in PNAS co-authored by SFI Science Board member and External Professor Tim Kohler sketches an eight-century baby boom among southwestern Native Americans starting around 500 A.D., followed by a crash, that Kohler says offers a warning sign to the modern world about overpopulation.

The researchers examined data from thousands of human remains found over the past century at hundreds of sites across the Four Corners region of the Southwest. These data enabled Kohler to assemble a detailed chronology of the region’s Neolithic Demographic Transition -- a shift from a hunter-gatherer way of life to an agrarian civilization. Bolstered by a steady diet of maize and the innovation of food storage, the Puebloan population expanded. Villages formed and the trappings of modern civilization began to emerge.

Interestingly, says Kohler, the researchers found that birth rates in some areas during this period were so high they likely exceeded the highest in the world today.

By 900 A.D., after a several-hundred-year population increase in the region, birth rates began to fluctuate but remained high. Then in the mid-1100s, a severe drought hit the region and population began to decline. By 1300, the Puebloans had all but vanished.

Although it's not entirely clear why the Puebloan population dissipated so quickly, Kohler argues that a changing climate likely prevented the land from sustaining a population that had grown too large. A dwindling population likely left the Puebloans vulnerable to attack.

"They didn't slow down -- birth rates were expanding right up to the depopulation," Kohler says. "It was a trap. A Malthusian trap but also a violence trap."

"Population growth has its consequences," he adds.

Read the paper in PNAS (June 30, 2014)

Read the article in the Albuquerque Journal (July 7, 2014)

Read the article in the Santa Fe New Mexican (July 2, 2014)

Read the news release from Washington State University (June 30, 2014)

Read the UPI article (June 30, 2014)

Read the article in Discover (June 30, 2014)

Read the article on NBCNews.com (June 30, 2014)