Biology Reference
In-Depth Information
sapiens
rather than a new species. The issues of mentality and brain size
were, once again, front and center, and they coalesced in the specific
pathology that these workers attributed to LB1. As was asserted for
Pithe-
canthropus erectus
when it was discovered nearly 120 years ago, LB1 was sup-
posedly a
Homo sapiens
who suffered from microcephaly, which literally
means “small headedness.” One contemporary researcher who espouses
the microcephalic interpretation has even been quoted as referring to
camp raised doubts about whether
Homo floresiensis
was intelligent enough
to have produced the stone tools found in Liang Bua and elsewhere on
Flores, although it is highly unlikely that the tools were made by anyone
else for the variety of reasons that were discussed in chapter 6.
The main thing that led some scientists to suggest that LB1 was a
microcephalic, of course, was her extremely small brain. As is always
the case, the volume occupied by LB1's brain would have been less than
the capacity of her cranium, because the brain occupies the braincase
along with fluids, vessels, nerves, and membranes. With a cranial capac-
ity of 417 cm
3
, the size of LB1's brain would have fit not only within the
range of brain sizes for microcephalics but also within the ranges for the
great apes and australopithecines. As we shall see, however, brain size
alone does not a microcephalic make!
microcephaly
Microcephaly is a condition in which individuals have abnormally small
heads because their brains failed to grow normally. It may be present at
birth, or it may develop during the first few years of life when the face
continues growing, but the brain and braincase fail to keep up. Micro-
cephalic children have small heads with sloping foreheads but relatively
large faces, an appearance that becomes more exaggerated in the lucky
ones who live to be adults. This appearance has led to the unkind appel-
lation “pinheads.”
12
Microcephaly is a complex syndrome. A variety of genetic muta-
