Human and Neanderthal Evolution Like ‘Game of Thrones,’ Scientists Say

A replica of a Neanderthal skull Neanderthal-Croatia/Museum/Nikola Solic/Reuters

New analysis of 17 skulls from a long-studied Spanish cave might contain clues about Neanderthal evolution, according to Science paper published today.

A research team led by Juan-Luis Arsuaga, a paleontologist at Madrid’s Complutense University, has discovered that the skulls feature both Neanderthal-derived features and the physical traits of more primitive humans. This means that Neanderthals might have “developed their defining characteristics separately, and at different times—not all at once,” according to the scientists. The discovery might help answer ongoing questions about hominims—the technical term for human-like primates, also sometimes referred to as “hominids”—during the Middle Pleistocene period, approximately 400,000 to 500,000 years ago.

The recently studied skull collection leading to this discovery—from the Sima de los Huesos (Pit of Bones) site in northern Spain, which has been excavated since 1984—comprises 17 skulls. While some have been examined before, seven are discussed for the first time in this paper. The entire site has yielded 7,000 human fossils, of at least 28 individual hominims.

“We think that a Game of Thrones scenario probably describes hominid evolution in Eurasia and Africa,” Arsuaga told reporters today during a telephone press conference. “Some of the big houses were closely related. All of the houses were much more differently related.”

Researchers have known the basics of Neanderthal evolution for some time: A few groups of early humans split away from their cohorts in Africa and East Asia and traveled to Eurasia; the Eurasian groups then evolved into Neanderthals. A few hundred thousand years later, modern humans, who evolved in Africa, also moved to Eurasia. The two species interacted and even mated, but over time modern humans became the more dominant hominims.

The new skull analysis provides a much closer look into Neanderthal evolution. These specimens include skulls with Neanderthal features in the face and teeth but with a brain case that looks more like earlier hominims. This suggests that the Sima de los Huesos skulls are of Neanderthal lineage but are not direct ancestors of this hominim variety, the researchers claim.

Some of the more Neanderthal facial and dental characteristics are tied to chewing.

“The incisors show a great wear, as if they had been used as a ‘third hand,’ typical of Neanderthals,” Arsuaga said in a statement. Other skulls from this period that have been recovered in other parts of the world don’t have these dental and facial features, suggesting the coexistence of various Neanderthal-like lines of hominims, each living in its own region.