The anatomy of the vocal tract — the structures in the throat and mouth that produce speech — is not well-preserved in ancient bones.

The hyoid bone, which is part of the vocal apparatus and whose shape reflects the anatomy of the larynx and tongue, is occasionally preserved and has been used as evidence about the speech potential of Neanderthals.

Neanderthal hyoid bones appear similar in shape to those of modern humans, which has been taken as evidence that Neanderthals had vocal tracts capable of speech sounds.

The FOXP2 gene — a gene involved in the fine motor control of the vocal tract and facial muscles, and which is associated in modern humans with the ability to produce the rapid, precise movements that speech requires — has been analyzed in Neanderthal DNA.