Biology Reference
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Figure 24. Outlines of the right sides of endocasts from microcephalics and
LB1. (A) Superimposed outlines of three microcephalic endocasts from our
sample, which include the smallest (276 cm
3
) and the largest (671 cm
3
). These
outlines reveal a generally similar shape in different-sized microcephalic
endocasts despite the diversity of our sample. (B) The same three outlines
with the outline of LB1's endocast (417 cm
3
) superimposed (depicted by the
shaded area). The endocast of LB1 has a long, low profile with an occipital
pole
(op)
that projects farther back than the cerebellum
(ce)
compared with
the microcephalics' endocasts. The underneath surface of LB1's frontal lobe
(f)
is also more expanded, and the temporal pole
(tp)
projects farther forward
compared with that feature in the microcephalics' endocasts. Created by Kirk
Smith, Mallinckrodt Institute of Radiology; modified from Falk, Hildebolt,
et al., “LB1's virtual endocast, microcephaly” 2009.
cut off-center, and our analyses depended on precise measurements of
Martin, on the other hand, estimated measurements for the Indian's
endocast on the basis of an uncorrected midline, which we found at
least as problematic as relying on line drawings in lieu of precise mea-
surements or quibbling about different batches of plaster that were used
to cast two parts of a skull.
44
In the end, our research on microcephaly turned out to be worth-
while, not just for assessing LB1's virtual endocast, but also because
of another, unanticipated result that is related to recent research on
comparative molecular genetics. A number of genetic mutations have