Flo’s Little Brain - The Fossil Chronicles - page 116

information related to vision, smell, and taste and contributes to the
regulation of social behavior. Interestingly, damage to it impairs our
ability to understand vocal and facial emotional expressions. 15 One can
only wonder if this would also have been true for hobbits.
LB1's biggest surprise was the two whopping convolutions noted
above (arrows 6, figure 18 C and D), which can be seen right above her
nose in Kirk's reconstruction (figure 16). This region (along with the
nearby squared-off corners) is part of Brodmann's area 10 (BA 10), or
the frontopolar cortex. Different parts of the brain are distinguished
by their arrangements of cells at a microscopic level. In classical neuro-
anatomy, these areas were assigned numbers by Korbinian Brodmann
(1868 - 1918) in the order in which he studied them. For example, Broca's
speech area in humans is composed of Brodmann's areas 44 and 45
in the left hemisphere. The size of BA 10 in hominins following their
evolutionary split from chimpanzees has outpaced the expansion of
other parts of the frontal lobe, and it is now twice as large in relative
terms as the same region in great apes . 16 It may, in fact, have the largest
volume of any region in the human frontal lobes. The neurons in BA
10 of humans are more widely spaced and have more complex connec-
tions compared with those in BA 10 of apes. 17 BA 10 of humans is not
manifested in separate convolutions, like Hobbit's, however, perhaps
because the human brain is big enough to accommodate most of this
region without forming extra bulges. 18
BA 10 appears at microscopic levels in brains of nonhuman primates
but is not so large that it contains visible convolutions like the two in
Hobbit. Conspicuous convolutions in particular parts of animals' brains
often indicate that the functions that they serve are especially impor-
tant for their lifestyles. For example, some species of New World mon-
keys have prehensile tails that act as highly skilled fifth limbs, and their
brains (and endocasts) have extra convolutions in the areas that sense
and control their tails, convolutions that other monkeys lack. Although
some apes' and early hominins' endocasts that are similar in size to
Hobbit's have whispers of these two convolutions in their frontopolar