Fossil face bones discovered in Spanish cave may belong to first ancient humans in Western Europe

Skeletal fragments discovered in northern Spain offer new clues about the earliest human species to arrive in Western Europe. These fossil remains, nicknamed "Pink" by researchers (derived from their fondness for the band Pink Floyd), date back 1.1 to 1.4 million years ago.

These findings have been published today in the journal *Nature*. The research team, led by Rosa Huguet of the Catalan Institute of Human Paleoecology and Social Evolution and scholars from Rovira i Virgili University, stated: "This fossil represents the earliest human face discovered to date in Western Europe."

Spain boasts Western Europe's richest collection of early human fossils, with many discoveries made in the numerous caves of the Atapuerca Mountains. In 2022, Dr. Huguet and her colleagues discovered fragments of cheekbone, maxilla, eye, and nose bones in the Sima del Elefante (Elephant Pit) cave at Atapuerca. When pieced together, they form the left side of an ancient human face.

Previously, the team had discovered a jawbone approximately 1.2 million years old in a shallower layer of the same cave, belonging to an unidentified hominin. But the newly discovered fossils provide a clearer picture of the human species to which it belonged. These discoveries surprised researchers. The human family tree—the genus *Homo*—dates back approximately 2 million years.

*Homo erectus*, who lived until at least 250,000 years ago, was the first human species to have body proportions like our modern humans (*Homo sapiens*) and to walk upright. Until now, the earliest identifiable ancient humans found in the Atapuerca region were *Homo antecessor* ("Pioneer Man") from around 850,000 years ago. This species had a prominent nose, a distinct characteristic of modern humans. But "Pink" appears to have different facial features.

Dr. Huguet stated, "The facial features of ATE7-1 [Pink] are more primitive, similar to *Homo erectus*, especially in its flat and undeveloped nasal structure." Laura Martín-Francés of Monash University in Melbourne and the Spanish National Research Center for Human Evolution, a co-author of the study, said that, unfortunately, there were not enough bones to determine "Pink's" sex or develop a model or artistic impression of its face.

Dr. Martín-Francés, a dental anthropologist involved in the reconstruction of "Pink," stated that it was only possible to draw "Pink's" face "from the nose down." "Since we are missing the forehead portion, it is really difficult to draw the rest." Nevertheless, the team believes there is enough evidence to tentatively classify "Pink" as near to *Homo erectus*, referring to its proximity to *Homo erectus*.

Dr. Huguet said, "We did not know that another species might have existed in Western Europe... [around the same time as *Homo antecessor*]. But surprisingly, this is not the case." While "Pink" belongs to a population that may have arrived in Europe before *Homo antecessor*, researchers say it is too early to say whether the two species may have overlapped.

Researchers added that animal and plant remains collected at the site indicate that "Pink" lived in a habitat that was more humid and warmer than the Atapuerca Mountains today. Dr. Huguet said, "The environment around Sima del Elefante was an open, humid forest landscape with trees, shrubs, and waterways, where Mediterranean-type plants such as hazelnut trees were found."

Other evidence suggests that near-*Homo erectus* used basic tools. Dr. Huguet said, "Pebbles and flakes made of quartz and flint, all local materials... suggest that they may have been used to process animal meat." In addition to this, a rib from a deer-like animal was found with clear cut marks on it.

Andy Herries, an archaeologist at La Trobe University (who was not involved in the study), said that there has been some debate about the distinction between *Homo antecessor* and *Homo erectus*. Professor Herries, who discovered the oldest *Homo erectus* remains in Africa, said, "I know some of my colleagues don't necessarily think there is a huge difference between *Homo antecessor* and *Homo erectus*."

He said that complicating matters further is that the *Homo antecessor* fossil being compared to "Pink" is a juvenile. "Their morphology changes as they grow and adapt, so we don't fully know what an adult *Homo antecessor* might have looked like." But he said "Pink" is "a very cool fossil." He said, "Atapuerca is absolutely an amazing complex of sites. Amazing discoveries."

"Basically, what's happening is that the dates when Europe was occupied are constantly being pushed back further." Professor Herries said that these findings could provide clues about the possible routes humans took out of Africa and into Europe. To date, the oldest ancient human fossils found outside of Africa are 1.8 million years old. These fossils were found in Dmanisi, Georgia, which is considered a crossroads between Asia and Africa.

So, did those ancient humans migrate westward, reaching places like Spain? Professor Herries said, "Some people think that Europe was occupied from the direction of Dmanisi." Other experts believe that Spain's rich fossil evidence—combined with "Pink"—suggests that ancient humans traveled more directly from Africa to Europe. "Maybe hominins crossed the Strait of Gibraltar into Spain." Unfortunately, Professor Herries said, "Pink" does not resolve this debate.