If you were able to travel back some 130,000 years and chance upon a Neanderthal, you might find yourself telling them about some of humanity's greatest inventions, such as spanakopita and TikTok. The Neanderthal would have no idea what you were saying, but might be able to hear you perfectly, picking up on the voiceless consonants "t," "k" and "s" that appear in many modern human languages.
A team of scientists has reconstructed the outer and middle ear of Neanderthals and concluded that they listened to the world much like we do. Their study, published in Nature Ecology & Evolution, found that Neanderthals had the anatomical ability to perceive a similar range of sounds as modern Homo sapiens, including upper speech frequencies that mainly involve consonant production.
Any insight into how Neanderthals heard can offer clues into one of the most-debated, unresolved questions about the ancient hominids: whether Neanderthals spoke.
For decades, the debate hinged on a single Neanderthal bone: the horseshoe-shaped hyoid in the vocal tract that is a key to speaking. The only complete Neanderthal hyoid was recovered from a skeleton in a cave in Israel in the 1980s, and its similarity to a human hyoid led to a flurry of attempts to reconstruct the Neanderthal voice box and vocal tract.
But it is difficult to draw sweeping conclusions from a single fossilized bone, let alone one untethered from the skeleton and no longer held with long-lost soft tissues. "You don't get a lot of preserved Neanderthal tongues," said Anna Goldfield, an anthropologist and host of "The Dirt" podcast.
In the new study, the researchers used high-resolution CT scans of ear structures in five Neanderthals, 10 modern Homo sapiens and nine early hominids who lived before Neanderthals. The team created 3-D models of these ear structures and ran the measurements through a software model to calculate the way sound energy moves into the ear canal and winds its way toward the cochlea.
The researchers calculated the range of frequencies in which at least 90% of the sound power reaches the inner ear — the "sweet spot" of hearing, Quam said. The study found the Neanderthal ear's sweet spot extended toward frequencies specifically dedicated to consonant production. "The use of consonants distinguishes human language from mammalian communication," Quam said.
In fact, the study found Neanderthals' sweet spot was the same as modern human hearing, whereas the early hominids from Sima de los Huesos had a hearing range somewhere between chimpanzees and modern humans.