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as the superior temporal (or parallel) sulcus (figure 5) is much greater in
humans than in apes because of
Homo sapiens
's greatly expanded parieto-
occipito-temporal association cortex.
Taking his mentor's theory very much to heart, Dart identified what
he thought was a lunate sulcus on Taung's endocast. Despite Taung's
tiny brain size, he believed that the lunate sulcus was located far back
in a (supposedly) humanlike position and that this indicated enhanced
intelligence in
Australopithecus
(see figure 6):
This group of beings . . . had profited beyond living anthropoids by setting
aside a relatively much larger area of the cerebral cortex to serve as a store-
house of information concerning their objective environment as its details
were simultaneously revealed to the senses of vision and touch, and also of
hearing. They possessed to a degree unappreciated by living anthropoids
the use of their hands and ears and the consequent faculty of associating
with the colour, form, and general appearance of objects, their weight, tex-
ture, resilience, and flexibility, as well as the significance of sounds emitted
by them. In other words, their eyes saw, their ears heard, and their hands
handled objects with greater meaning and to fuller purpose than the corre-
sponding organs in recent apes. They had laid down the foundations of that
discriminative knowledge of the appearance, feeling, and sound of things
Despite these accolades, Dart did not think that
Australopithecus
had
evolved to the point of having language, because Taung's endocast was
not expanded in a particular part of the temporal lobe (which processes
hearing, memory, and certain aspects of vision). This was, in fact, a
major reason why he regarded Taung as a man-ape rather than a true
human, although he proposed that
Australopithecus
should be put in a
Dart's belief that Taung was intellectually advanced compared with
living apes rested squarely on his identification of the lunate sulcus. I
have gone into some detail about this particular sulcus because it is a
piece of evidence that will recur in discussions about my own efforts to
understand its significance for Taung and, later, for Hobbit. Meanwhile,
