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Archaeological Headlines By JESSICA E. SARACENI
Thursday, December 18

Possible Viking Vessel Identified in Canada


Cathedral Builders Reinforced Stone With Iron


Royal Entryway Discovered at Herod’s Palace


More Headlines
Wednesday, December 17

The Secret Strength of Roman Concrete


2,800-Year-Old Farm House Will Be Preserved


Laser Technology Reveals Rickets in Mary Rose Sailors


8,000-Year-Old Olive Oil Found in Israel


Tuesday, December 16

Agricultural Practices Contributed to Tikal’s Decline

CINCINNATI, OHIO—The many residents of the Maya city of Tikal, located in Guatemala, would not have been able to import enough food to meet their needs without draft animals, wheeled vehicles, or navigable waterways. A team led by David Lentz of the University of Cincinnati analyzed surveys, satellite imagery, archaeological information, forest growth data, and pollen data. Phys.org reports the team determined that Tikal’s residents employed intensive agricultural practices, such as terracing, irrigation, and slash-and-burn cultivation to sustain the population’s growth during the Late Classic Period, from 600 to 850 A.D. But these methods rely on consistent annual rainfall, and the effects of a dry period in the middle ninth century may have been exacerbated by the clearing of forests and the pavement of large areas. Lentz and his colleagues conclude that by the late ninth century, the system could no longer provide enough food, fuel, and drinking water for the population and Tikal was abandoned. For laser scans of Tikal's monuments, see "The Past in High-Def."

Khirbet Summeily Yields 10th-Century B.C. Clay Seals

STARKVILLE, MISSISSIPPI—Six clay seals unearthed at Khirbet Summeily, an early Iron Age site in southern Israel, suggest that there was more political complexity in the region at that time than had been previously thought. “These appear to be the only known examples of bullae from the tenth century [B.C.], making this discovery unique,” said Jimmy Hardin of Mississippi State University and co-director of the Hesi Regional Project. The bullae came from sealed written documents, at a site that had been thought to be a rural farmstead in a border area. “You have either political or administrative activities going on at a level well beyond those typical of a rural farmstead,” he explained. Two of the bullae have complete seal impressions, two have partial seal impressions, and two others are blank. Two of the bullae were blackened by fire, and one of them has a well-preserved hole where the string used to seal the document passed through the clay. “Generations of scholarship have suggested [that the people of Khirbet Summeily were] farming, but over the past few years, we have slowly realized that humans rarely farmed this region. It was a pasture. Shepherds tended sheep and goats under the protection of their government. Finding the bullae this past summer strongly supports our idea that Khirbet Summeily was a governmental installation,” commented Jeff Blakely of the University of Wisconsin-Madison, and co-director of the Hesi Regional Project. The tenth century B.C. is often referred to as the time of the biblical kings David and Solomon. To read about unusual artifacts dating to the same period that were unearthed in Israel, see "Artifact: Iron Age Figurines."

Extinct Wild Horses Contributed to Today’s Domestic Breeds

COPENHAGEN, DENMARK—A new study, led by Ludovic Orlando of the Center for GeoGenetics at the University of Copenhagen, compared the DNA obtained from two well-preserved horse fossils between 16,000 and 43,000 years old from arctic conditions in Russia, with those of the Przewalski’s horse—the only surviving population of wild horses—and five breeds of modern horses, which were first domesticated some 5,500 years ago. The team detected a set of 125 candidate genes favored by humans in modern horses that involve physical and behavioral traits, including genes that were already known to evolve under strong selection in horses. Some of those genes affect the development of muscles and bones, which would have been necessary for utilizing horses for transportation. Other genes favored by domestication control the animals’ response to fear. Negative impacts could be seen in the increasing levels of inbreeding and the accumulation of deleterious mutations that can occur in small populations. The study revealed that Przewalski’s horses have a proportion of deleterious mutations similar to domesticated horses, due to their recent near extinction. Finally, the genomes revealed that the ancient wild horses contributed to the modern population of domesticated horses, but not to the Przewalski’s horses. “This confirms previous findings that wild horses were used to restock the population of domesticated horses during the domestication process,” said co-author Mikkel Schubert of the Center for GeoGenetics. For more on horse genetics, see "Dappled Horse Paintings Decoded by DNA."

Easter Islanders Enjoyed Sweet Potatoes

DUNEDIN, NEW ZEALAND—Monica Tromp of the University of Otago and John Dudgeon of Idaho State University have re-examined the plant microfossils found in dental calculus of the Polynesians who lived on Rapa Nui, or Easter Island, in the years before European contact. Their previous research had suggested that palm may have been a staple plant food for the population, but other evidence indicates that the palm went extinct shortly after the island was colonized. For the new study, the researchers identified starch grains in the calculus removed from 30 teeth. All of the identified starch grains were consistent with modern sweet potato. None of the grains were similar to banana, taro, or yam, which are all thought to have been part of the islanders’ diet. They also tested the skins of modern sweet potatoes grown in soil similar to Easter Island’s, and found that the skins of the potatoes incorporated palm phytoliths from the soil. “So this actually bolsters the case for sweet potato as a staple and important plant food source for the Islanders from the time the island was first colonized,” said Tromp. “This research also shows that the plant foods you find evidence for in dental calculus can come from the environment that foods are grown in and not necessarily from the food itself—this finding has the potential to impact dental calculus studies worldwide,” she explained. For more on a similar study, see "Dental Calculus Offers Direct Evidence of Milk-Drinking."