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Braindance New discoveries about human origins and brain evolution. By Dean Falk. New York Henry Holt. 1992. ix + 260 pp. ISBN 0-8050-1282-6 $24.95 (cloth)

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AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 89:265-273 (1992)
Book Reviews
tor theory”. Owing to gravity, habitual bipedalism causes a rearrangement of cranial
blood
vessels that may be accomplished in
BRAINDANCE:
NEWDISCOVERIES
ABOUT HUMAN
of
two ways. Some hominids, such as
one
ORIGINS
AND BRAINEVOLUTION.
By Dean
Falk. New York: Henry Holt. 1992. ix + robust australopithecines and the Hadar
260 pp. ISBN 0-8050-1282-6. $24.95 hominids called Australopithecus afarensis,
cooled their brains by using the occipital/
(cloth).
marginal sinus to shift blood to the vertebral
In Braindance, Dean Falk writes clearly plexus when they stood up. Other hominids
snd engzgingly about three issues of jntpr- had, and modem humans have. a different
est to biological anthropologists-the rela- and more complicated system that relies on
tionship of bipedalism and brain evolution transverse sinuses and emissary veins to
in early hominids, reasons for large brain- drain blood from the skull.
Bipedalism allowed the ancestors of gracsize increase in early Homo, and what brain
anatomy can tell us about the configuration ile australopithecines to cope with the therof the hominid family tree. These complex mally stressful savanna and to utilize its
issues are challenging to explain and tie to- varied resources. (According to Falk, robust
gether with ease, but Falk has done so and australopithecines “kept cool among the
more; she has written a book that is both ac- trees” while graciles “ventured afield on
cessible to a wide audience and valuable to a foot” (p. 161). This distinction is important
scientific one. I learned from this book (it to her conclusions and requires better supeven motivated me to track down some pri- port than Falk gives it here.) Once the radimary sources cited in its pages), and suspect ator system of cooling was in place among
other readers of this journal would as well. graciles, it “released thermal constraints
Falk starts the book with a theme that she that had previously kept brain size in check
sustains throughout, her view that anthro- (p. 163). The actual kickoff factor (which
pologists since Dart have overinterpreted Falk neatly distinguishes from the release of
australopithecine brain features as human- constraint just described) relates to “prolike. She makes a convincing case, based longed selection for better information propartly on her own research on hominid en- cessing that included a hefty dose of speech
docasts housed worldwide, that in fact aus- (p. 188).For Falk, language has a long evotralopithecine cerebral cortices are apelike. lutionary history; using this perspective
Only with Homo came “elaborations” of (which fits the primatological evidence
three cortical features-the frontal lobes, nicely), she relates language and brain evoassociation cortex, and lateralization of the lution in a plausible way.
Discovery of two different systems of
hemispheres. These elaborations were subtle in that no new structures evolved; rather, brain cooling led Falk to two conclusions
just as in dance, subtle shifts in timing and about hominid phylogeny. First, gracile and
robust australopithecines were separate for
emphasis were the key t o major changes.
After providing the reader with a clear a long time before the fossil record “picks
foundation in brain anatomy, Falk relates them up”. Second, Australopithecus afarenher other important conclusions back to it. sis, which resembles robust australopitheShe neatly sums up her thesis on p. 76: “I cines in the brain-cooling system, is unlikely
believe that selection for bipedalism in early to be a direct human ancestor. These suggesgracile australopithecines kicked off the tions, and the way that Falk interprets
train of events that would eventually lead to KNM-WT 17000 (the Black Skull) and OH
even more advanced brains. Bipedalism is 62 (termed Homo habilis by Donald Johanthe key to understanding human brain evo- son), are likely to be the most controversial
lution.” She explains the link via her “radia- aspects of the entire book.
0 1992 WILEY-LISS. INC
266
BOOK RE:VIEWS
I found much to agree with (or to admire
even when I did not agree) in Braindance.
Falk‘s basic scenarios are well-supported by
the data that she reviews relating to brain
evolution, although her conclusions are
somewhat difficult to evaluate without extensive knowledge of brain anatomy. Falk,
however, covers so many topics-including
primate behavior, sex differences in the
brain, origins of writing, and speech-that
some get short shrift. In arguing for a long
evolutionary heritage for human aggresqion, for example, Falk wmkes it sound as if
violence and killing occurs frequently in
chimpanzees. She doesn’t tell the reader
that the chimpanzee “murders” at Gombe
occurred during a relatively brief time span,
nor does she mention that Gombe is a provisioned site, which might be relevant.
Rather, she writes (p. 216): “When chimpanzees find an unfortunate stranger, the marauding group holds their victim to the
ground and attacks him or her with their
hands and feet and teeth. They do not stop
until the victim is completely incapacitated
or dead.” Such a statement, offered as a generalized description of chimpanzee behavior, is surely inaccurate and sensational. In
another chapter, Falk’s discussion of the relationship between Neandertals and modern humans is confusing. She seems to say
(p. 172) that Neandertals should be considered as “a direct ancestor of Homo sapiens,” then equates Homo sapiens sapiens
with Cro-Magnon (p. 173). In a few other
places where Falk deviates from discussing
brain evolution, she is on similarly shaky
ground.
I had a few reservations about the book‘s
style. Falk writes (p. 8)that “the long-established tradition of selective interpretation
and advocacy in hominid paleontology . . . is
slowly being replaced by a new spirit of scientific objectivity.” Falk apparently doubts
the objectivity of some of her fellow biological anthropologists, and names some in passages that seem destined to further the very
lack of cooperation and mutual respect that
she complains about. But, as explained by
Roger Lewin in his book Bones of Conten-
tion, selective interpretation may largely be
due t o preconceived ideas and bias of which
the investigator is quite unaware. Falk
makes it sound as if scientists have only to
try and they will achieve objectivity, and
seems to link certain conclusions with objectivity and others with bias. This is somewhat simplistic. Second, I wish that Falk
had used inclusive language rather than
adopting “man” to stand for all humans. At
times Falk is enlightening on women’s roles
in human evolution, but a t others her perspective ia outdaled. She considers it piausible, for example, that Paleolithic artists
were primarily male because they would
have been more adept a t reaching the areas
of caves used by artists, and includes a quote
(p. 117) from an expert on sex differences
who suggests that although women have
greater digital dexterity than men, they use
it not to become neurosurgeons but to do
needlepoint.
In sum, however, Falk writes so clearly
and interestingly about brain anatomy and
evolution that Braindance should be considered a significant contribution to both biological anthropologists and to the general
public. It is imperative that scientists communicate with the public in a way that enables people to see how apparently disconnected pieces of research actually fit together,
and how they matter. Falk does this and
makes it enjoyable along the way. The first
clue that Braindance might be fun as well as
informative comes upon glancing at the back
cover, where can be found neither the traditional blurbs of praise nor a picture of the
author, but rather, a photo of Dean Falk‘s
brain! (It is labelled as the right side, obtained via magnetic resonance imaging.)
Enjoyment of the book is also enhanced
through Falk‘s evident enthusiasm for her
work, and by the very creative and unusual
drawings (credited to Joyce Crocker) found
on each chapter’s opening page.
BARBARA
J. KING
Department of Anthropology
College of William and Mary
Williamsburg, Virginia
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cloth, discovering, falk, henry, holtz, 1992, evolution, braindance, isbn, origin, brain, human, new, dean, york, 1282, 8050, 260
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