Originally, researchers identified these scraps as belonging to Neanderthals, the early cousins of humans who went extinct about 30,000 years ago. However, the new study found the bones to belong to modern Homo sapiens. (Agencies)
The teeth and the bone were found in the San Bernardino Cave in the 1980s in a rock layer dating back to Neanderthal times, approximately 28,000 to 59,000 years ago.
"The taxonomical discrimination of the species was based mainly on the layer the human fossil was found instead of the morphological features," or shape and size of the bones, study researcher Stefano Benazzi, a physical anthropologist at the Max Planck Institute for Evolutionary Anthropology in Germany told 'LiveScience'.
The size and shape of the teeth were consistent with belonging to Homo sapiens, but their rock layer suggested Neanderthal.
A look back at the excavations revealed murky geology - at some point in the late middle ages, a wall to seal off the cave had been built, potentially disturbing the rock layers and preventing the researchers from using the layers as proof of age.
Benazzi and his colleagues analyzed one of the teeth, a molar, found in the cave. First, they took a look at the shape of the tooth using micro-computed tomography (CT), a scanning method that allows researchers to create virtual 3D models of an object. They also sampled for mitochondrial DNA, a type of DNA passed down the maternal line.
Next, they used radiocarbon dating to determine the age of the tooth. Finally, they analysed molecular traces in the tooth to determine the individual's diet. They found the tooth was not Neanderthal. The shape was somewhat ambiguous, but suggestive of a Homo sapiens' tooth.
The DNA looked far more human than Neanderthal and instead of being at least 30,000 years old, the tooth dated back to between AD 1420 and 1480.
The diet analysis revealed that the ratio of plants and meat eaten by the tooth's owner was consistent with the diet of a medieval Italian who ate millet, a plant not even introduced to Italy until 5,000 years ago or later.
Though the researchers did not chemically analyze the other tooth and finger bone, their sizes and close association with the molar suggest that they, too, are medieval in origin.
Originally, researchers identified these scraps as belonging to Neanderthals, the early cousins of humans who went extinct about 30,000 years ago. However, the new study found the bones to belong to modern Homo sapiens.