A fossilized skull fragment of Homo sp. unearthed in central Spain offers paleoanthropologists a fresh window into the story of ancient humans who lived in Europe hundreds of thousands of years ago.
A Homo heidelbergensis, a Neanderthal and a Cro-Magnon. Image credit: SINC / José Antonio Peñas.
The fossil is a fragment of a parietal bone — one of the bones that form the sides and top of the skull.
The specimen was found embedded in rock breccia during excavations at the Middle Pleistocene locality of Ruidera within the Ruidera Lakes Natural Park in the Castilla-La Mancha region.
Labeled RVH-1, it represents the first human fossil ever recovered from the site.
“It was an incredible and fortunate surprise,” said Dr. Mario Modesto-Mata, a paleoanthropologist at the Centro Nacional de Investigación sobre la Evolución Humana (CENIEH) and the International University of La Rioja.
“We went through a range of emotions, from initial skepticism and disbelief to immense joy once it was confirmed that it could only be human.”
Using a combination of uranium-series dating and optically stimulated luminescence, the researchers estimated the fossil-bearing layer to be up to 224,000 years old.
“This fossil is only the tip of the iceberg,” added Dr. Sara Díaz Pérez, a paleoanthropologist at the University of Wrocław.
“Ruidera still has much to reveal about human evolution in Europe, and we are convinced that it will continue to yield discoveries of major scientific importance.”
Anatomically, RVH-1 stands out for its relative thickness and its pronounced angle at the temporal line, a ridge on the side of the skull.
Both measurements place the fossil toward the upper end of the range seen in other Middle Pleistocene human fossils from Europe.
“This is a thick cranial structure, similar to the morphology seen in other crania also regarded as archaic, such as the Ceprano specimen in Italy and the fossils from Caune de l’Arago in the French Pyrenees,” said Dr. Daniel García Martínez, a paleoanthropologist at the Complutense University of Madrid.
“The unusual anatomy of RVH-1 indicates that hominin populations — the group of primates that includes modern humans and their closest fossil relatives — with unexpected characteristics were still living in the Iberian Peninsula at that time.”
“These traits had been inherited from ancestral lineages and persisted until relatively late in the Middle Pleistocene.”
The scientists caution against drawing sweeping conclusions from a single, partial bone.
Rather than assigning the specimen to a specific species, they opted to classify it simply as Homo sp., while noting its morphological similarities to what is often labeled Homo heidelbergensis.
“The discovery reinforces the idea that human evolution in Europe was not a linear process, but rather a complex scenario in which different populations with distinct evolutionary histories coexisted,” said Dr. Carlos Palancar, a paleoanthropologist at the National Museum of Natural Sciences.
“It provides information about the populations that inhabited the interior of the Iberian Peninsula during this period and places Ruidera in a privileged position on the European map for the study of human evolution during the Middle Pleistocene,” Dr. García Martínez said.
The team’s paper was published today in the Journal of Human Evolution.
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D. García-Martínez et al. The first human fossil from the Ruidera site (Castilla-La Mancha, Spain): A partial parietal and its implications for Middle Pleistocene hominin variability in Southern Europe. Journal of Human Evolution, published online July 30, 2026; doi: 10.1016/j.jhevol.2026.103866
