Archive for the ‘biological archaeology’ Category

Neanderthal teeth reveal lead exposure and difficult winters

October 31st, 2018
Neanderthal teeth reveal lead exposure and difficult winters

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A new study of oxygen isotope ratios and heavy metals in the tooth enamel of Neanderthals who lived and died 250,000 years ago in southeast France suggests that they endured colder winters and more pronounced differences between seasons than the region’s modern residents. The two Neanderthals in the study also experienced lead exposure during their early years, making them the earliest known instances of this exposure.

Enduring harsh winters

Tooth enamel forms in thin layers, and those layers record the chemical traces of a person’s early life—from climate to nutrition to chemical exposures—a little like tree rings on a much smaller scale. Archaeologist Tanya Smith of Griffith University and her colleagues examined microscopic samples of tooth enamel from two Neanderthal children from the Payre site in southeastern France. The teeth were radiocarbon dated to around 250,000 years ago, and the set of samples recorded about three years of life.

One important clue to past environments is oxygen, which comes from the water a person drank or the plants they ate. The ratio of the oxygen-18 isotope to oxygen-16 depends on temperature, precipitation, and evaporation. Generally, higher ratios of oxygen-18 indicate warmer, drier conditions with more evaporation.

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Posted in Archaeology, biological archaeology, isotope analysis, Neanderthals, paleoanthropology, paleoclimate, science, teeth | Comments (0)

Ancient skull found among debris in burned Brazilian museum

October 25th, 2018
Ancient skull found among debris in burned Brazilian museum

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Archaeologists are celebrating the recovery of an 11,500-year-old skull from the burned rubble of the National Museum of Brazil following a devastating fire on September 2. The skull belongs to a woman, now nicknamed Luzia, who died in a cave in southeastern Brazil early in the history of the settling of the Americas. Archaeologists in the 1970s unearthed about a third of her skeleton, including her remarkably well-preserved skull, her pelvis and lower spine, part of her right femur (the large bone of the upper leg), her left tibia (the shin bone), and left radius (one of the bones of the forearm).

An early American

According to radiocarbon dating done in 2013, Luzia died sometime between 11,243 and 11,710 years ago, which places her bones among the oldest evidence we have of the early population of the Americas. When archaeologists retrieved the charred, cracked pieces of skull and femur from the remains of the museum’s first floor earlier this week, they salvaged a rare and vital source of information about how humans spread through the Americas.

Although archaeologists also found flint tools at the site, Luzia herself had been left alone in the cave with no other human remains nearby. That suggests an unexpected death, perhaps in an accident or an encounter with large Pleistocene wildlife. And at just under 1.5 m (5 ft) tall, Luzia certainly wouldn’t have been much of a match for a saber-toothed cat.

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Posted in 3d scanning, ancient DNA, Archaeology, biological archaeology, museums, paleoanthropology, paleogenomics, peopling of the americas, pleistocene, science, South America, South American archaeology | Comments (0)