At a rescue excavation of an open-air prehistoric site, Tourville-la-Rivière in the Seine Valley of Normandy in northern France, archaeologists were in for a surprise - the discovery of three long human arm bones. The experts detail the unearthing, description, and analysis of these three partially crushed bones: a left humerus, radius, and ulna from the same upper left limb.
    The authors of the study used a spectroscopic technique (electron spin resonance, or ESR) and a radiometric dating technique (Uranium-thorium dating, or U-series dating) to determine an approximate age for the Tourville human remains. They then scanned the bones in an X-ray and processed them on the computer to generate a 3D cross-sectional image of the bones, allowing them to examine their shapes and characterize them within the Neanderthal lineage.
    As a result of the analyses, the authors estimate the bones most likely belonged to a single Neanderthal adult or older adolescent from 200,000 years ago. This discovery may be the first example of the Neanderthal lineage in northwestern Europe, and the authors suggest that it may provide insight into the relationship of the Tourville remains to other human fossils from ~781,000-126,000 years ago, a period known as the Middle Pleistocene era.
    The researchers also describe how the shape and other features of these bones are more similar to Neanderthals than to humans. They also noted that the connective tissue between the tendon and the humerus featured a rather unusual long ridge or crest - this formation is often found in older modern humans, and is located at a section of the bone connected to the deltoid, or back shoulder muscle. Since this muscle allows for the rotation and lifting of the arm, this crest may be the result of a repetitive throwing motion. The researchers suggest that this throwing motion could be connected to activities like spear throwing.
    The Tourville fossils may be the oldest found in France during a rescue excavation, and may provide new material for a limited sample of fossils from northwestern Europe. Previously discovered fossil samples from the Middle Pleistocene era mainly consist of skulls and teeth, so the discovery of three arm bones may reveal an unusual shape in the connective tissue that may provide new evidence for how Neanderthals may have behaved. While the authors concede that the precise cause of this abnormality in the connective tissue is unclear, it poses an interesting question for further research on how Neanderthals behaved and whether this change may have impacted their survival as a species.

Edited from Plos Blogs (1 December 2014)