modern human range.In fact,most specimens older than roughly 250,000
years before the present do not differ from the chimpanzee.Put another
way,beginning with Neanderthals,all humans show a relatively broad
palate with a palate length reduced from the ancestral condition.Figures
14.6 and 14.7 also show that palatal proportions typical of modern
humans are found in some early fossils.It is no surprise that these cases
are all members of the early Homosample,with australopithecines
falling at the low end or outside the modern human range.Discussion and Summary
Data and inferences from bony regions surrounding critical areas for the
production of human speech sounds indicate that the potential for utter-
ing formants typical of modern speech and song may be ancient adap-
tations in hominids.Judging from the limited fossil record that preserves
relevant morphology,in early members of the genus Homothe external
cranial base is flexed,which presumably indicates a lowered larynx with
an expanded and probably bent supralaryngeal vocal tract.The lungs (as
measured by rib cage shape in one specimen) and nasal chamber (based
on morphology of several fossils) also attained a modern human shape
in these early Homopopulations.Similarly,at least in some specimens,
the general proportions of the oral cavity were comparable with modern
those of humans at about 1.5 million years ago.
Inferences about speech- and sound-production abilities are big steps
(maybe leaps) from these bits of fossilized morphology.Yet,others used
even fewer data to show that some members of Homolacked the ability
to produce a human range of linguistic sounds.Our statements here do
not necessarily justify extrapolations to language ability or the capacity
to produce music,but it is reasonable to deduce that the presence of
some morphological details indicate the ability to produce specific
sounds.From our view of the available physical data,evidence for the
ability to produce speech sounds appears early in the fossil record.In
fact,such ability may have happened in independent lines of hominids
and may have emerged as part of an adaptation completely unrelated to
linguistic ability,such as dietary adaptation.At least in Homodated to
around 1.5 million years ago,a set of morphological features emerged
that are correlated to speech sound production in modern humans.It
may be no coincidence that with the appearance of these early Homo
fossils other evidence is preserved further hinting at linguistic compe-
tence.This includes brain expansion and evidence for hemispheric
laterality (Falk,this volume;Holloway 1976,1983,1985),appearance
of more sophisticated tool inventories,evidence for handedness in the231 Fossil Evidence for the Origin of Speech Sounds