DNA Study Delves Into Dog Domestication

LONDON, ENGLAND—According to a Cosmos Magazine report, a new study of ancient DNA spanning 100,000 years and 30,000 generations indicates that dogs came from two different populations of wolves. Pontus Skoglund of the Francis Crick Institute and his colleagues sequenced the genomes of 72 ancient wolves whose remains were found in Europe, Siberia, and North America. The scientists also analyzed data from the genomes of 68 modern wolves, and 169 modern and 33 ancient dogs. Early dogs in Siberia, the Americas, East Asia, and Europe appear to have descended from an eastern Eurasian species of wolf, while early dogs in the Middle East, Africa, and southern Europe came from this eastern Eurasian species and a second, distinct population related to modern wolves in southwest Eurasia. The study also suggests that wolves were either domesticated more than once and the dogs were eventually mixed together, or the eastern Eurasian species of wolf was domesticated just once, but then some of these early dogs then mixed with their wild relatives. “We found several cases where mutations spread to the whole wolf species, which was possible because the species was highly connected over large distances,” Skoglund added. In particular, a gene related to the shape of the skull and jaw spread to every wolf in just 10,000 years, between 30,000 and 40,000 years ago. This change may have allowed the predators to adapt to the prey available during the Ice Age, he said. Read the original scholarly article about this research in Nature. To read about dog and wolf bones unearthed at a Bronze Age site on the Russian steppe, go to "Wolf Rites of Winter." 

Children’s Burials Hint at the Survival of Aztec Customs

MEXICO CITY, MEXICO—The Associated Press reports that researchers from Mexico’s National Institute of Anthropology and History (INAH) have uncovered the remains of four children who were buried on the outskirts of the historic center of Mexico City. After the Spanish conquered the Aztec capital in 1521, they pushed the Indigneous Mexica population to the edges of the city. The children are thought to have been buried between 1521 and 1620 according to Aztec customs, even though these practices had been outlawed by the Spanish. For example, a newborn was buried in a bulbous-shaped pot with other pots placed around it. The bones of a bird were found in another pot with blue coloring, which has been associated with water. And a girl between the ages of six and eight at the time of death was buried with a large Aztec-style clay figurine depicting a female figure holding a child. Her remains showed possible signs of anemia, malnutrition, or infection, indicating that the Mexica population endured hard times after the conquest. For more on the world of the Aztecs, go to "Under Mexico City."

New Dates Obtained for South Africa’s Australopithecus Fossils

WEST LAFAYETTE, INDIANA—According to a statement released by Purdue University, Australopithecus fossils discovered deep in South Africa’s Sterkfontein Caves are more than a million years older than previously thought. An international team of scientists from Purdue University, the University of the Witwatersrand, and the University of Toulouse Jean Jaurès dated the breccia where the fossils were found to be between 3.4 and 3.7 million years ago. The process included using accelerator mass spectrometry to measure radioactive nuclides in the rocks that were produced by exposure to cosmic rays, in addition to careful mapping of earlier excavations and a study of how the cave’s sediments accumulated. Previous attempts to date the cave’s Australopithecus fossils involved examinations of animal fossils found near them and the age of the cave’s flowstones, said Darryl Granger of Purdue University. But, he explained, the animal bones had been disturbed during earlier investigations, and young flowstone can be deposited in old sediment, creating the potential for inaccurate dates. Read the original scholarly article about this research in Proceedings of the National Academy of Sciences of the United States of America. To read about an Australopithecus anamensis cranium unearthed in Ethiopia, go to "Artifact."

World War II Warship Discovered in Deep Waters

DALLAS, TEXAS—The Associated Press reports that the wreckage of the USS Samuel B Roberts has been discovered under 23,000 feet of water off the coast of the Philippines by Caladan Oceanic, an undersea technology company. The destroyer escort, which carried a crew of 224, sank on October 25, 1944, in a fight with Japan’s navy during the Battle of Leyte. Eighty-nine sailors from the Samuel B. Roberts were lost, many from wounds and shark attacks while waiting to be rescued. Three other American ships also sank on that day, including the USS Gambier Bay and the USS Johnston, which was discovered last year under 21,000 feet of water by the same team of explorers. A lack of reliable data on a possible location has prevented a search for the last of the four ships, the USS Hoel. To read more about underwater discoveries of sunken World War II vessels, go to "Wrecks of the Pacific Theater."

Pottery Analysis Offers Clues to Caribbean Island Trade Routes

GAINESVILLE, FLORIDA—According to a statement released by the Florida Museum of Natural History, analysis of pottery samples from 11 islands in the Bahamas and Turks and Caicos has revealed where the vessels originated and offered clues to how they were used. The chemical composition of the pottery was compared to the levels of copper, nickel, chromium, and antimony found in island soils. Pottery made by the Lucayans, or People of the Islands, from the soils of the Bahamas and Turks and Caicos is known as Palmetto Ware. It is thick and soft due to the grainy soil blown in from the Saharan Desert. But the study indicates that much of the pottery found on these islands was made on the northwest coast of Hispaniola, a larger Caribbean Island located to the south. Pottery made in Hispaniola could have been used to transport a variety of goods to and from the Bahamas and Turks and Caicos. The researchers knew that the Lucayans were related to people in Hispaniola, explained Emily Kracht of the museum’s Ceramic Technology Lab, and this study indicates that their relationship endured over hundreds of years through pottery. Read the original scholarly article about this research in the Journal of Archaeological Science: Reports. To read about the origins of an ancient Taino woman whose remains were found on the island of Eleuthera, go to "World Roundup: Bahamas."

New Thoughts on Australia’s Underwater Stone Tools

PERTH, AUSTRALIA—According to a statement released by the University of Western Australia (UWA), a re-evaluation of underwater stone scatters off Western Australia’s Pilbara coast, conducted by a team of researchers including members of the Murujuga Aboriginal Corporation, indicates that the sites may not be as old as previously thought. Researchers from Flinders University, UWA, James Cook University, and Airborne Research Australia had suggested that the underwater sites at Cape Bruguieres were undisturbed, and could be thousands of years old. The new study, led by geoarchaeologist Ingrid Ward of UWA, found that the scattered stone artifacts are not permanently submerged, and are likely to have been moved by waves and currents away from where they were first discarded. Ward said that the artifacts' age is unknown at this time—they could be 200 years old, 2,000 years old, or 20,000 years old. Read the original scholarly article about this research in Geoarchaeology. For more on the initial discovery of the tools, go to "Around the World: Australia."