Radiocarbon Dating: Neanderthals Not as Smart as We Thought

The site in question is the Grotte du Renne at Arcy-sur-Cure, a famous home of human remains and artifacts, including bones from and objects thought to have been made by Neanderthals as well as bones and objects from non-Neanderthals. The original excavation attributed the lowest levels (in the sediment) of artifacts to Neanderthals and the highest to non-Neanderthals, with the age of the youngest artifacts approximately 28,000 years old and the oldest artifacts around 45,000 years old.

Of special interest since that time, however, has been the identity of the middle layers of artifacts. The artifacts from the lowest, Neanderthal layers are generally inferior to the artifacts from the higher, (thought to be) non-Neanderthal layers. But in the middle are sophisticated tools and ornaments found alongside Neanderthal teeth. Elsewhere, similar objects have been found with Neanderthal skeletons. The evidence thus pointed to Neanderthals’ intelligence and humanity.

So what’s the problem? New York University archaeologist Randall White and a team of researchers including radiometric dating expert Thomas Higham of the University of Oxford conducted a new radiocarbon dating analysis of the location. The analysis indicates “that the archaeological layers at the site are so mixed up that ornaments and tools once attributed to Neandertals could actually be the work of modern humans, who lived in the same cave at a later date,” ScienceNOW reports. Specifically, the middle layers give the youngest radiocarbon date; the upper layers, a medium date; and the lowest layers, the oldest date.

For White, the problematic results show that the Grotte du Renne “should be disqualified from the debate over [Neandertal] symbolism,” given the layers cannot be reliably interpreted as older and younger based on their depth, with the middle layers now deemed too recent given assumptions about when Neanderthals died out. The scientists speculate that somehow the archaeological levels were mixed over time, with “artifacts made by modern humans [perhaps having] moved down into levels long thought to be associated with Neandertals,” according to ScienceNOW.

As always, the scientific evidence may be interpreted differently depending on one’s worldview. For old-earth scientists, the radiocarbon dating is effectively accepted as gospel—unchallenged, with conclusions about archaeological layers forced around the dating results. For Bible-believing youth-earth scientists, the Bible is “accepted as gospel,” so to speak, with the direct implication that Neanderthals were fully human—which comports with the archaeological evidence. What must yield, then, for young-earthers is the idea that radiocarbon isotopes are actually the reliable clocks that old-earthers assume them to be. Thus, the study either confirms one’s faith in the biblical model of humanity and casts further doubt on radiocarbon dating, or else it voids years of archaeological work in understanding our ancestors’ tool design.