unique characteristics of modern human emerged, then it is important to
discover when and how our ancestors became capable of speech. For even
if the ability to produce the sounds of speech may exist independently of
it, language as we know and use it could never have developed inde-
pendently of the ability to produce speech. The basic vibrations that we
manipulate to create the sounds that become speech are produced in our
throats, at the vocal cords. But these vibrations are modified higher in the
throat, by the muscles that surround the pharynx, a space that loops high
above the larynx, or voice box, which contains the vocal cords.
In apes (and in newborn humans), the larynx lies high in the throat,
and the skull base is flat. In the resulting short pharynx, sounds cannot
be modified much. As the infant human grows, however, the skull base
bends and the larynx descends, producing a long pharynx in which a
greater variety of sounds can be produced. At least in part, this is a key
to the remarkable vocal gymnastics that we perform each time we utter
a sentence. Neither apes nor newborn humans can produce the range of
sounds necessary for this, and the contour of the base of the skull does
seem to be a fairly reliable indicator of the vocal tract’s potential for
producing the sounds necessary for speech, even though the shortness of
the face also plays a role. On the evidence of the bending seen in the base
of the Bodo skull, it seems that much of this potential may well have
been present in Homo heidelbergensis, as long ago as 600,000 years.
Still, with the face as yet unretracted to produce balanced proportions of
the pharynx and oral cavity, it is doubtful that the full human vocal
apparatus was in place in Homo heidelbergensis, and there is no other
evidence to suggest that these hominids actually spoke.
As with earlier hominid species, the appearance of Homo heidelber-
gensis is not accompanied by any notable change in technological equip-
ment. The sediments from which the Bodo cranium was derived contain
mostly Mode 1 artifacts, although Mode 2 tools (handaxes) are also doc-
umented in them. Beyond this, though, there is not much to be said at
this point about the lifestyle of the Bodo hominid, and we have to turn
to Europe for a better behavioral record of H. heidelbergensis. And as it
happens this record is quite impressive, even though it is mostly limited
to a handful of sites in France and Germany.
One of these sites is the cave of Arago in southern France in which
were found the various H. heidelbergensis fossils that allow us to link
the Heidelberg lower jaw to a specimen with a face. At Arago the hom-
inid fossils were mixed in with broken animal bones and crude artifacts
of Mode 1 type, and it seems that this site was indeed a place where
hominids at least periodically gathered and carried out daily activities,
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