Biology Reference
In-Depth Information
microcephalics that we could CT scan and submitted a proposal to the
National Geographic Society for financial support. It was a good thing,
too, because we learned during the first week of July 2005 that three sci-
entists from Germany ( Jochen Weber, Alfred Czarnetzki, and Carsten
Pusch) had just submitted a technical comment to
Science
in which they
claimed to have data from 19 microcephalic modern humans that showed
LB1's endocast was, indeed, from a microcephalic rather than a new spe-
cies.
Science
invited us to provide an accompanying response. Both pub-
In their comment, Weber and his colleagues focused on one particu-
lar microcephalic endocast, for which they reported a cranial capacity
of 415 cm
3
compared with our measurement of 417 cm
3
for LB1. They
also calculated the same six ratios that we used to capture information
about overall brain shape in LB1. As discussed above, these ratios con-
firmed what our eyes suggested about the general shape of LB1's endo-
cast
—
namely, that it resembled the endocasts of
Homo erectus
(figure 17).
Remarkably, Weber's results suggested that their key microcephalic
endocast could have passed for the identical twin of LB1's endocast:
“The values for our specimen are nearly identical to those obtained for
H. floresiensis,
which are shown in parentheses: breadth/length = 0.85
(0.86); height/length = 0.68 (0.68); frontal breadth/length = 0.64 (0.65);
(breadth minus frontal breadth)/length = 0.21 (0.21); (breadth minus
Weber's comment also included a figure that compared our images of
the front, back, top, and right side of LB1's endocast with corresponding
views from what was identified as a modern microcephalic endocast,
although it was not clear whether or not the latter was supposed to be
from their key microcephalic specimen.
In our response, we pointed out that Weber's team had failed to pub-
lish the four measurements that they used to calculate the six ratios.
(Publishing the raw data along with the ratios is standard practice, as
we had done in our
Science
report.) We also discussed why we did not
believe that the four images that were compared with our different views
