The Brain of the H. floriensis "Hobbit"
Translucent skull of LB1 containing red virtual endocast.
Image courtesy of Kirk E. Smith of the Mallinckrodt Institute of Radiology of Washington University
The brain of the diminutive ancient human, Homo floresiensis, resembled
that of Homo erectus or perhaps even Australopithecus and not the
brain of a modern human with a disease or developmental disorder, new findings published in the 4 March 2005 issue of the journal Science
H. floresiensis evidently crossed the sea to reach the
Indonesian island of Flores, where its bones were found near tools and some
evidence for the use of fire. If the tools and other artifacts are related to H.
floresiensis, they would suggest surprisingly advanced behaviors for a tiny
hominin with an ape-sized brain.
A U.S., Australian and Indonesian research
team analyzed three-dimensional representations of the H. floresiensis
brain, reconstructed from the recently discovered skull known as LB1. Dean Falk
and colleagues compared this "virtual endocast" with endocasts from
great apes, Homo erectus, Australopithecus africanus, Paranthropus
aethiopecus, and Homo sapiens, including a pygmy and a human with
abnormal or "microcephalic" brain growth.
Although LB1's brain/body
size ratio is more like that of Australopithecus, the brain's overall
shape is closest to that of H. erectus, the authors report.
does show some differences from H. erectus, such as an expanded
temporal lobe. The authors suggest in the 3 March 2005 Science Express that these differences are consistent with
the idea that this species was capable of higher cognitive processing despite
its tiny brain, although more research is necessary to determine whether this
was the case.
3 March 2005