The largest human fossil collection ever discovered at a single site has shed new light on the origin and evolution of Neanderthals, a distinct species of ancient humans. The collection includes seventeen skulls from the Sima de los Huesos (Pit of Bones) cave in Northern Spain.
Described in the journal Science, the fossils represent the earliest set of Neanderthal-like traits dating back 430,000 years ago or 100,000 years earlier than previously reported.
The skulls show Neanderthal features in the face and teeth, but not, in the braincase. This combination of features is normally associated with more primitive hominids. The samples support the idea that evolutionary changes emerged at different times and not all at once. The work suggests that facial modification, particularly related to chewing, was the first step in Neanderthal evolution.
Lead author Juan-Luis Arsuago, Professor of Paleontology at the Complutense University of Madrid was surprised how similar the different individuals were.
“The other fossils of the same geological period are different and don’t fit in the Sima pattern,“ he said. “This indicates that more than one evolutionary lineage appears to have co-existed at the same time, with the Sima site representing one closer to the Neanderthal.”
Sima de Los Huesos has been excavated continuously since the early 1980s with the recovery of nearly 7,000 human fossils and 28 complete skeletons.