Re: Researchers Analyze Hominid Brains

Stephen Jones (sejones@ibm.net)
Tue, 23 Jun 1998 21:46:34 +0800

Reflectorites

Attached is a news article, which if borne out, would further
underline the uniqueness of Homo sapiens:

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Yahoo! News

AP Headlines Friday June 12 5:13 AM EDT

Researchers Analyze Hominid Brains

WASHINGTON (AP) - Researchers who used a modern medical tool
to analyze fossilized skulls suggest that early human-like creatures
living more than 2 million years ago had smaller brains than once
believed.

Glenn C. Conroy of Washington University in St. Louis reported that
his analysis of the skulls from the early ancestors of modern humans
suggests that "something is very wrong with previous interpretations
of early hominid brain capacity."

Conroy is the lead author of a study appearing today in the journal
Science.

The finding "is about to wreck havoc on our view of hominid
evolution," said Dean Falk, an anthropologist at State University of
New York, Albany. Conroy's work may force a reworking of theories
about the timing of brain development among the early ancestors of
modern human beings, Falk said.

"The ramifications for hominid brain evolution may be profound,"
Falk wrote in a commentary in Science.

Conroy is co-developer of a way to analyze fossilized skulls using
computed tomography, or CT, scans. The system lets researchers see
inside skull fossils and reconstruct the skull from fragments, allowing
a precise measure of brain size.

Using the technique, Conroy analyzed the skull of "Mr. Ples", the
name given for the fossil of an Australopithecus africanus, a hominid
that lived in what is now South Africa. A. africanus are thought to be
early ancestors of modern humans that lived in Africa 3.5 million to
2.5 million years ago.

Conroy found the skull had the brain capacity of about 515 cubic
centimeters.

Earlier estimates of the skull had put the brain size at about 600 cc,
far larger than the mid-400 cc range thought to be typical for A.
africanus brains.

Falk said the brain size is larger than average for hominids from that
era, but far smaller than what experts had predicted for the skull.
Modern humans have a brain size of about 1,350 cc.

Conroy also analyzed another A. africanus skull and found it was 370
cc, not the 440 cc that had previously been assigned to the fossil.

"I was shocked," Conroy said in a statement. "There was supposed to
be a quantitative leap in brain size that distinguished early hominids
from apes, yet 370 cc is the size of a chimpanzee brain."

Conroy said his findings suggest the brain sizes estimated for other
early hominid skulls may be wrong, that "current views on the tempo
and mode of early hominid brain evolution may need re-evaluation."
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Steve

"Evolution is the greatest engine of atheism ever invented."
--- Dr. William Provine, Professor of History and Biology, Cornell University.
http://fp.bio.utk.edu/darwin/1998/slides_view/Slide_7.html

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3 Hawker Avenue / Oz \ Steve.Jones@health.wa.gov.au
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Perth, West Australia v "Test everything." (1Thess 5:21)
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