No one disputes that European colonization of the New World devastated native populations. But the timing and scale of that demographic crash are sources of debate among archaeologists and historians. Some believe that Old World diseases, for which Native Americans had no resistance, spread even faster than explorers and colonists, in some regions wiping out peoples before they had any direct contact with Europeans. A team led by Harvard University archaeologist Matthew Liebmann has now tested that hypothesis in northern New Mexico, which the Spanish first reached in 1539. Using lidar images of 18 ruined villages once occupied by the Jemez people, the team estimated the population of these Puebloans through time. They found that it was stable throughout the sixteenth century—well after the first Spaniards arrived in New Mexico. “In this part of the Southwest, massive pandemics did not arrive ahead of or with the initial Spanish occupation,” says Liebmann.

But the study also showed that the founding of a mission church near the Jemez almost a hundred years later had deadly consequences. Liebmann found that the population dropped by almost 90 percent between 1620 and 1640, probably as a result of sustained contact with disease-ridden livestock from the mission. His team also discovered that the number of fires in the area began to increase after this time, probably a consequence of forest regrowth following the drastic depopulation.

Archaeologists have long known that ancient societies on Peru’s north coast killed male prisoners of war and drank their blood in grisly sacrifice ceremonies. Now researchers have found an unusual twist on that scene: the remains of six young women, sacrificed in a ritual in about A.D. 850. Their bones were found under the floor of a mudbrick temple complex in Pucalá, near the city of Chiclayo. The women show no signs of disease and had been wrenched into odd positions. Four lay atop each other in a single grave, and two others rested a few feet away, accompanied by a baby llama. Most are missing rib bones, indicating that their remains were left exposed and that their organs had been eaten by vultures after death, a “purification rite” that the bodies of male sacrifice victims were also subjected to, says archaeologist Edgar Bracamonte of the Royal Tombs of Sipán Museum.

Human sacrifices were often public spectacles in ancient Peru, but not in this case. “They were buried in a ritual space that was surrounded by high walls, indicating a private context,” Bracamonte says. The burial occurred “at a time of great ideological change,” he adds, when the old Moche culture was yielding to a new order, known as Lambayeque. The Moche buried their dead on a north-south axis. These women were buried on a careful east-west axis, their heads toward the Andes Mountains to the east. Ceramics accompanying the women are also from the Andes, suggesting that the women and the society that buried them originated in the mountains and came to the coast by invasion or migration.

Archaeologists have identified what they believe is the earliest archaeological evidence of the consumption of tea: plant remains in two tombs excavated in Tibet and Chang’an, today called Xi’an, a city that marks the beginning of the Silk Road in northern China. The finds contain traces of caffeine and theanine—substances particularly characteristic of tea. The tombs are more than 2,000 years old, indicating the beverage was consumed during the Han Dynasty (206 B.C.–A.D. 220). A Chinese document from 59 B.C. that mentions a drink that might be tea was previously the earliest known record of the beverage. Tea does not grow near the tombs, so the discovery indicates that the Silk Road was a “much more complicated and complex long-distance trade network than was known from written sources,” says researcher Dorian Fuller, an archaeobotany professor at University College London. Tea-producing regions, including remote areas of China and even Myanmar, he adds, had “well established supply lines” feeding into the Silk Road.