A publication of the Archaeological Institute of America

Special Introductory Offer!
Archaeological Headlines By JESSICA E. SARACENI
Wednesday, December 17

The Secret Strength of Roman Concrete

BERKELEY, CALIFORNIA—An international, interdisciplinary team of scientists has used beams of x-rays at the Advanced Light Source of the U.S. Department of Energy Lawrence Berkeley National Laboratory to study the longevity and endurance of Roman architectural concrete. A reproduction of the Roman volcanic ash-lime mortar that had been used to build the walls of Trajan’s Markets was observed over the 180-day curing process, and compared to 1,900-year-old samples of the original. The team discovered that a crystalline binding hydrate prevents microcracks from spreading, so that the concrete maintains its chemical resilience and structural integrity, even when earthquakes occur. In addition, mixing Roman cement releases less carbon into the environment than mixing modern Portland cement, which is made by heating a mix of limestone and clay to a higher temperature than that required to form the Roman version. “If we can find ways to incorporate a substantial volumetric component of volcanic rock in the production of specialty concretes, we could greatly reduce the carbon emissions associated with their production and also improve their durability and mechanical resistance over time,” explained Marie Jackson of the University of California, Berkeley. To read more about how Roman concrete was used, see "Rome's Lost Aqueduct."

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

ROSH HA-‘AYIN, ISRAEL—A 23-room farm house dating to the eighth century B.C. was unearthed in central Israel ahead of a construction project. “Farm houses during this period served as small settlements of sorts whose inhabitants participated in processing agricultural produce. The numerous wine presses discovered in the vicinity of the settlement indicate the wine industry was the most important branch of agriculture in the region. A large silo, which was used to store grain, shows that the ancient residents were also engaged in growing cereal,” said excavation director Amit Shadman, on behalf of the Israel Antiquities Authority. Built during the time of the Assyrian conquest, the farm house was inhabited during the Persian period and the Hellenistic period. In fact, a rare, Greek silver coin bearing the name of a military leader was found on one of the floors of the building. A lime kiln dating to the Ottoman period was also uncovered. The site will be preserved and opened to visitors. To read about an intriguing discovery at another farm site in Israel, see "Crusader-Era Seal Unearthed in Jerusalem." 

Laser Technology Reveals Rickets in Mary Rose Sailors

LONDON, ENGLAND—Raman spectroscopy, a non-destructive laser technology, has been used to analyze leg bones of sailors who died on King Henry VIII’s flagship, the Mary Rose, which sank in battle on July 19, 1545. The tests were conducted at the Royal National Orthopedic Hospital, as part of a study by a team from University College London, the Science and Technology Facilities Council, and The Mary Rose Trust. Some of the bones appeared anatomically healthy, and some were abnormal in shape. The results of the testing confirmed that the abnormal bones also had chemical abnormalities, perhaps caused by rickets, a metabolic bone disease caused by deficiencies in the diet. “This is the first time that this laser technology has been used to study bone disease in archaeological human bone. We have identified chemical changes in the bones, without damaging them. There is strong evidence to suggest that many of the sailors had suffered from childhood rickets and we hope to apply the Raman technique to the study of modern day rickets,” said Dr. Jemma Kerns, RAMAN Clinical Study Manager at University College London and the Royal National Orthopedic Hospital. To read more about the Mary Rose, see "History's Top 10 Greatest Shipwrecks."

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

JERUSALEM, ISRAEL—Traces of olive oil have been detected on 8,000-year-old pot sherds unearthed at the site of Ein Zippori, located in the Lower Galilee. “Although it is impossible to say for sure, this might be an olive species that was domesticated and joined grain and legumes—the other kinds of field crops that we know were grown then. Those crops are known from at least 2,000 years prior to the settlement at Ein Zippori. With the adoption of olive oil the basic Mediterranean diet was complete,” Ianir Milevski and Nimrod Getzov of the Israel Antiquities Authority said in a statement reported by The Times of Israel. The well-preserved oil closely resembles modern olive oil. Evidence of olive oil production has been found at the 7,700-year-old site of Kfar Samir, now underwater off the coast of Haifa. To read about another recent Neolithic discovery in Israel, see "7,500-Year-Old Well Discovered."

More Headlines
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."

Monday, December 15

Denmark's Ribe May Be Older Than Previously Thought

AARHUS, DENMARK—A new study suggests that the coastal town of Ribe, the oldest town in Scandinavia, is older than had been originally thought. “If Ribe began as a city in the early 700s, then it was long before the Vikings and thus casts new light on our understanding of this period,” Sarah Croix of Aarhus University told The Copenhagen Post. She reviewed archaeological data collected in the 1980s by archaeologist Stig Jensen, who died before compiling the results of his partial excavation of a house on St. Nicholas Street. Croix found that tools, such as millstones for grinding grain, show the wear and tear of daily use. She thinks additional houses, perhaps with fire places, could be found nearby, indicating that Ribe was a more permanent habitation site, in addition to being a harbor and commercial area. To read in-depth about the oldest evidence for Viking raiding in the Baltics, see "The First Vikings."

Racton Man’s Bronze Dagger Is 4,200 Years Old

CHICHESTER, ENGLAND—The tests results are in, and Racton Man’s bronze dagger, discovered by a metal detectorist in 1989, has been dated to 4,200 years ago, making it the earliest securely dated bronze object ever found in Britain. At the time, James Kenny, an archaeologist at Chichester District Council, went to the burial site and uncovered the skeleton and additional rivets. “What makes his dagger so stunning is the rivet-studded hilt. Its design is distinctively British, but of a significance is the fact that it dates to the transition from copper to bronze metallurgy. This dagger is bronze and so this item would have been incredibly rare at the time; its color and keen hard edge would have distinguished it from the more common copper objects in use,” explained archaeologist Stuart Needham. Analysis of Racton Man’s bones by a team from the London Institute of Archaeology shows that he stood more than six feet tall, and was more than 45 years old at the time of his death, perhaps caused by the unhealed wounds found under the right armpit and to the upper right arm. He also suffered from spinal degeneration, a chronic sinus infection, tooth decay, and an abscess. Isotope analysis of his teeth by scientists from Durham University suggest that he grew up in southern Britain. To read about a weapon from the same time period, see "Artifact: Bronze Age Dagger."

The Roman Method of Water Management

UTRECHT, NETHERLANDS—The Romans carefully managed the water supply in the Mediterranean region through an extensive grain-trade network in order to provide food for an estimated 70 million people, according to a new study published in Hydrology and Earth System Sciences. Environmental scientist Brian Dermody of Utrecht University, and a team made up of hydrologists from the Netherlands and classicists from Stanford University, determined how much water it took to grow the staple crop, then used a hydrological model to calculate grain yields, also accounting for climate and soil type. Maps of the Roman landscape and population were employed to estimate where agricultural production and food demand were greatest, and the grain trade was simulated, based upon the Roman transportation network. “If grain yields were low in a certain region, they could import grain from a different part of the Mediterranean that experienced a surplus. That made them highly resilient to short-term climate variability,” Dermody explained. But the stable food supply may have contributed to the eventual decline of the Roman Empire. As the population and urban centers grew, the system became more dependent upon trade and more vulnerable to climate variability. “We’re confronted with a very similar scenario today. Virtual water trade has enabled rapid population growth and urbanization since the beginning of the industrial revolution. However, as we move closer to the limits of the planet’s resources, our vulnerability to poor yields arising from climate change increases,” he said. To read about Roman water management, see "Rome's Lost Aqueduct." 

Skeletal Remains May Be Famed English Racehorse

NEWMARKET, ENGLAND—Skeletal remains of a carefully buried racehorse have been uncovered at the seventeenth-century royal stables at Palace House in eastern England, the site of a new National Heritage Center for Horseracing and Sporting Art. The remains could be those of Doctor Syntax, a stallion who won 36 races between 1814 and 1823. “Where it was buried, it would make sense. Doctor Syntax was euthanized here in 1838,” curator Graham Snelling of the National Horseracing Museum told The Telegraph. Archaeologist Chris Faine of Oxford Archaeology points out that Doctor Syntax is thought to have been 28 when he died, but the skeleton’s teeth suggest that this horse was 18 to 20 years old at the time of death. “There’s no trace of any other injuries on the skeleton. The skull was heavily smashed, which means I can’t tell from it whether it was euthanized,” he said. The location of the burial in the palace yard would indicate that animal was one of the king’s favorites. To read about the excavation of a WWI-era equine hospital, see "England's Real-Life War Horses."