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nitive neuroscientist Stanislas Dehaene that this part of the brain may
have been important in preliterate hunters and gatherers for “reading”
us that the wide temporal lobes of Hobbit were a feature that was evolu-
tionarily advanced toward the human condition, which was unexpected
(even unprecedented) in such a small brain. And hobbits were hunters
and gatherers.
Even more intriguing were the frontal lobes of LB1. For one thing,
they lacked the short fronto-orbital
(fo)
sulcus, which incises the edges
and courses underneath the frontal lobes in similarly sized ape brains
(near arrow 4, figure 18). As explained in chapter 4, absence of
fo
is con-
sidered an advanced trait, because this sulcus became buried within
hominin brains as their frontal lobes enlarged and became more convo-
luted over time. The general topography and orientation of the prefron-
tal cortex near arrow 4 on LB1's virtual endocast nonetheless appeared
similar to that of humans, although my colleagues from Mallinckrodt
and I were unable to identify specific sulci in this region that are associ-
ated with Broca's speech area in the left hemisphere of humans, because
the morphology was not clear. The language capability of hobbits
remains an open question, which we hope to address with the discov-
ery of additional skulls that reveal more morphology. Like language,
right- and left-handedness are advanced human characteristics that are
associated with asymmetrical brains. It is worth noting, then, that LB1's
endocast appears lopsided when viewed from above (figure 18D), in a
manner that is known to be statistically associated with left-handedness
in living people, particularly females.
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When seen from above, the most anterior part of LB1's endocast has a
humanlike squared-off shape at the “corners” of the right and left fron-
tal lobes (arrows 5, figure 18D), and two unusually large convolutions
straddle the midline (arrows 6). Together, these features give the front
end of Hobbit's endocast an almost ruffled appearance. The bottom
(orbital) surfaces of Hobbit's frontal lobes are also relatively swollen
(arrow 7, figure 18A). In living primates, this last region receives sensory
