Top 10 Discoveries of 2015
West Turkana (Kenya): Earliest Stone Tools By ZACH ZORICH
One of a number of stone tools unearthed in Kenya and thought to be 3.3 million years old - © MPK-WTAP
Stone toolmaking has been considered one of the defining characteristics of members of the genus Homo, but this year it was announced that newly discovered tools predate the first known humans. A research team led by Sonia Harmand and Jason Lewis of the Turkana Basin Institute at Stony Brook University found the tools at a site called Lomekwi 3 in Kenya. They are believed to be 3.3 million years old, predating Homo habilis—the first known member of the genus Homo—by about 700,000 years. A group of fossils roughly contemporaneous with the tools was discovered nearby in 1999 and dubbed Kenyanthropus platyops, a small-brained hominin that seemed unlikely to have used tools—until now. Harmand believes that stones were just one part of the early hominin toolkit and says, “Why not think that our ancestors from the beginning were using many, many tools?”
Johannesburg (Afrique du Sud): A New Human Relative By DANIEL WEISS
Skull of Homo naledi - Courtesy Wits University
Scientists have long searched for the transitional species between apelike australopithecines, such as Lucy (Australopithecus afarensis), and early humans, such as Homo habilis. And now, deep in the Rising Star cave system in South Africa, they may have unearthed it. When amateur cavers told Lee Berger, a paleoanthropologist at the University of the Witwatersrand in Johannesburg, that they had located hominin remains in the nearby cave system, he knew he could not make it in to retrieve them himself. The passageway was extremely narrow, just seven inches wide at one point. So Berger put out a call on Facebook for diminutive, non-claustrophobic scientists and recruited a team of six women who fit the criteria. Marina Elliott, an archaeologist from Simon Fraser University in Canada, was the first to enter the chamber. “I was stunned,” she says. “I shone my headlight around and picked up flashes of bone all over the place.” Elliott and her colleagues retrieved more than 1,500 specimens, from at least fifteen different individuals. A larger team of scientists, led by Berger, determined that the remains belong to a previously unknown species, which they named Homo naledi after its resting place—naledi means “star” in the local Sesotho language. The newly discovered species had a novel mix of primitive and modern features. Its head was tiny, with a brain the size of an orange, but its skull was humanlike in shape. Its hands were adapted for manipulating objects and its feet for walking upright, but its shoulders and fingers were built for climbing. “We never expected to see a combination of characteristics like this,” says John Hawks, a paleoanthropologist at the University of Wisconsin–Madison, “but they’re all in Homo naledi, and that’s surprising.” The researchers suspect Homo naledi may be among the earliest members of the genus Homo, which would mean it most likely existed around 2.5 million years ago. However, they have so far been unable to date the remains.
Sulawesi (Indonesie): The First Artists By DANIEL WEISS
Hand stencils believed to have been created more than 30,000 years ago have been found in limestone caves on the Indonesian island of Sulawesi - © Kinez Riza
Dating cave art is notoriously difficult. But a team of researchers has taken advantage of serendipitous conditions in caves on the Indonesian island of Sulawesi to establish that images there rival any known from Western Europe in terms of age. A stencil created as the artist blew pigment around a hand is at least 39,900 years old, they report, and a painting of a piglike animal was laid down at least 35,700 years ago. The researchers established the designs’ minimum ages by calculating the dates of deposits that had built up on top of the pigment. They had observed that, as mineral-laden water percolates through the caves’ limestone walls, calcite gradually accumulates on their surfaces. These deposits contain uranium, which decays to thorium at a known rate, so their age can be ascertained from the ratio of the two elements. The discovery raises a new question: Did people in Southeast Asia and Western Europe develop artistic expression independently, or was it pioneered by early humans before they left Africa? “We don’t know,” says Maxime Aubert of Griffith University in Australia, “but my opinion is it probably developed a long time ago, in Africa, and then it just spread out.”
Jamestown (USA):Jamestown’s VIPs By SAMIR S. PATEL
The graves of four eminent leaders of colonial Jamestown unearthed in the chancel of the settlement’s original church. Photo by Michael Lavin. Courtesy Jamestown Rediscovery Foundation (Preservation Virginia)
Jamestown, the first permanent English settlement in the Americas, is perhaps the United States’ most consistently prolific archaeological site. This year researchers have analyzed four previously excavated graves found in the chancel of the original 1608 church, a burial location surely reserved for prominent figures. Scientific, forensic, and genealogical work identified the remains of four members of Jamestown’s leadership—and turned up at least one new mystery.
The Chaplain—Reverend Robert Hunt, the chaplain of the settlement, is thought to have died in 1608. His remains were wrapped in a shroud instead of a coffin, reflecting his piety, and he was buried facing the congregation.
The Soldier—By contrast, Captain William West, killed by Native Americans in 1610, was buried in an ornate coffin, of which only the nails remain. His bones had high lead content, due to use of high-status drinking vessels, and found with him were the delicate remnants of a silk military sash.
The Nobleman—An even more elaborate, human-shaped coffin held the remains of Sir Ferdinando Wainman, Jamestown’s master of ordnance, who died during the “starving time” of 1609–1610, when some 70 percent of the colonists perished. His remains also had the high lead content of an aristocrat.
The Explorer—Captain Gabriel Archer, another victim of the starving time, had explored much of the northeast coast of America before the colony was established. His grave contained a fragment of a staff carried by British officers, as well as a silver box holding human bone fragments and a lead ampulla—almost certainly a Catholic reliquary. Was Archer a secret Catholic in the Protestant colony, or was the box repurposed and given some new significance for the first American outpost of the Anglican Church?
Teotihuacan (Mexique): Mythological Mercury Pool By ZACH ZORICH
A schematic of the Feathered Serpent Pyramid in ancient Teotihuacan, showing a tunnel leading to several underground chambers - INAH
Mercury is often found in Mesoamerican tombs in the form of a powdery red pigment called cinnabar, but its liquid form is extremely rare. So it was with some surprise that Sergio Gomez, an archaeologist with Mexico’s National Institute of Anthropology and History, discovered traces of liquid mercury this year in three chambers under the early-third-century A.D. Feathered Serpent Pyramid in the ancient city of Teotihuacan. Gomez believes the mercury was part of a representation of the geography of the underworld, the mythological realm where the dead reside. The silvery liquid was probably used to depict lakes and rivers. Since uncovering the entrance to a tunnel leading beneath the pyramid in 2003, Gomez has found five underground chambers containing thousands of artifacts, including many thought to be offerings, such as skeletons of large jaguars and wolves. Other objects, such as figurines made of jade from Guatemala and seashells from the Caribbean, indicate how far Teotihuacan’s influence extended. In addition to helping maintain the mercury in liquid form, the humidity and lack of oxygen in the underground chambers have preserved plant seeds and fragments of something that might be human skin.