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Facial growth 3rd ed. By D. H. Enlow. Philadelphia W. B. Saunders. 1990. 576 pp. $79

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samples. This analysis reveals, not too surprisingly, that specimens do tend to cluster
by geographic region. Interestingly, cluster
analysis places the major division in human
populations between a n African-Australian/
Melanesian group and everyone else; and,
except for some jumping about by the Amerindian samples, males and females cluster
fundamentally the same. Q-mode analysis is
then used to obtain separate axes of population shape differences and thus give some
idea as to what particular characters drive
the system. This analysis also identifies regional features and contrasts the major regional groups based on these features. Again
the overriding impression, in Howells’ view,
is one of basic world-wide homogeneity of
human cranial form.
Finally, Howells employs R-mode analyses to assess how the patterns of recent
human variation compare to certain fossil
hominids. He uses 2 Neandertals (La Ferrassie 1 and La Chapelle-aux-Saints), and
also Broken Hill, Jebel Irhoud 1, Skhul 5,
Qafzeh 6, Mladec 1, Keilor, and other late
Pleistocene/early Holocene specimens for
various analyses. With Mahalanobis D distances, Neandertals are clearly separated
from recent humans. With principal components analysis, Neandertals, Irhoud, Broken
Hill, and Skhul 5 and separated from all
other samples; and Mladec 1, Qafzeh 6, Fish
Hoek, and Keilor form a distinct subgroup
within the recent human samples and do not
associate with specific recent groups.
Based on these analyses, Howells argues
that modern human cranial homogeneity is
product of a shared evolutionary history for
all modern humans until a relatively recent
point in time. Specifically, he sees (1) no
support for regional populations deriving
from localized Homo erectus populations; (2)
no evidence for a specific common ancestry
for East Asians and AustraliansMelanesians;
and (3)no support for sub-Saharan Africa a s
the original source for all modern poeple (i.e.,
the “Out of Africa” models of recent fame).
While Howells takes pains to state that these
analyses are a “rather blunt instrument”
and do not provide “disproofs of anything” (p.
83), it is clearly his position that modern
humans are a monocentric phenomenon (although cranial analysis does not define the
center) and that Neandertals are not involved in the process. He also cites general
concurrence between his cranial data and
genetic data (from nuclear genetic polymorphisms rather than mitochondria1 DNA) to
support this view.
While I and others almost certainly would
quibble with his interpretations of late Pleistocene evolutionary history and its role in
the relative cranial homogeneity of recent
people, it seems inappropriate to dwell on
these issues in the face of the excellence of
the craniometric analysis. That analysis, after all, is the “meat” of the monograph and
constitutes its lasting scientific contribution. The monograph is replete with data.
Means and standard deviation of all measurements and angles for all samples are
presented, and the raw data are available on
request. The statistical analyses are carefully presented and documented. The text,
including statistical explanations, is clear
and concise. While I doubt that Skull Shapes
and the Map will have the theoretical or
methodological impact of Cranial Variation
in Man, it is nonetheless a solid contribution
and its data are sure to be widely used by
many appreciative researchers. Skull Shapes
should be carefully digested by everyone
with a n interest in craniometrics, analytical
methodology in physical anthropology, human variation, and the origins of modern
3rd ed. By D. H. Enlow. Philadelphia: W. B. Saunders. 1990. 576 pp.
$79.00 (cloth).
and developmental approach. In this way
Enlow, a n emeritus professor of Orthodontics, has distanced himself from the standard
medical literature which clusters these details in observations on “the monkey” or “the
child.” His interest in broader questions
Enlow’s work has long been appreciated by
evolutionary biologists for its comparative
Department of Anthroplogy
Northern Illinois University
DeKalb, Illinois
Brauer G (1988) Osteometrie. In R Knussmann (ed.):
Anthropologie. Handbuch der Vergleichenden Biolopie des Menschen. Vol. 1.Gustav Fischer: Stuttgart.
Howells WW (1973) Cranial Variation in Man: A Study
by Multivariate Analysis of Patterns of Differences
Among Recent Human Populations. Papers of the
Peabody Museum, Vol. 67. Cambridge: Harvard.
dates back to graduate studies done with the
vertebrate paleontologist A. S. Romer. Enlow is best known for his mapping of the
deposition and resorption patterns of both
the growing human and macaque skulls.
The first three chapters of Facial Growth
are classic Enlow. The reader is drawn into
the book with a discussion of how skull types
vary due to bauplan (dolicho- vs. brachycephalic), sex, and age. Technical terms are
introduced and often redundantly defined,
However, this book, like others on this subject, would benefit from a glossary.
In Chapter 2 Enlow differentiates basic
craniofacial developmental processes such
as surface remodelling, primary displacement (when bones fill space opened a t their
borders), and secondary growth (when bones
are moved by the growth of other, often
distant, bones). The current consensus on
osteogenesis a t the sutures, synchondroses,
and other cranial cartilages is that they passively expand a s craniofacial muscles, soft
tissue organs, and functional spaces grow
(e.g., pharynx, sinuses, otic and optic capsules). Enlow uses a balloon metaphor for
these expanding soft tissue units. Originally
hanging limply together, their centers move
away from each other as they inflate.
Chapter 3, “The Facial Growth Process,” is
the heart of the book. It covers the ontogeny
of the major regions of the skull. Along the
way the account is expanded to include competing models of craniofacial growth. Enlow
recounts the searches for “pacemaker cartilages,” such a s the nasal septum, sphenooccipital synchondrosis, and mandibular
condyle, which dominated research in the
middle third of this century. It was then
thought that like epiphyses, the cranial cartilages pushed developing craniofacial bone
segments into position, and that their
growth activity, as well as most craniofacial
morphology, was under extremely tight genetic control. That facial form in general is
heritable, not purely epigenetic, was obvious
long before Mendel, Darwin, and the New
Synthesis. Today, however, the search for
the mechanics behind craniofacial growth is
also aimed at securing a more exact notion of
the genetic contribution to morphology. As
Enlow puts it (p. 105): “This is a major
problem of our time and one that has more
than academic significance to students of
facial biology.” Enlow also details his now
famous maps of the depositional and resorptive surfaces of each cranial bone, including
the “V” principle and other complex patterns
of “cortical drift.”
Chapter 5, “The Pain of the Human Face,”
highlights the myriad ramifications that
have resulted from hominid bipedality, brain
enlargement, and orthognathy. Comparisons are made between humans and generalized mammals such as long faced dogs. In
one example, Enlow notes that in humans
the bony struts reinforcing the maxilla over
M1-‘ are not found over M3, concluding that
this tooth “has thus become effectively disenfranchised mechanically and phylogenetically” (pp. 168-169).
Orthodontists and anthropologists will
find the information in Enlow’s chapter on
malocclusions and the curve of Spee useful.
Various cranial bauplans are seen a s tending toward either Class I1 or 111 malocclusions. A short chapter on racial variation in
craniofacial form follows.
Eight of the 18 chapters in Facial Growth
are by contributors. 0. J. Oyen’s chapter on
mastication’s influence on facial morphology
should be of special interest to physical anthropologists. Oyen builds on the “level”
model of mandibular function established by
W. L. Hylander and A. C . Walker. Basically,
the model assumes that mammals can chew
hard on only one side of the jaw a t a time. In
this case a third class lever exists with the
fulcrum a t the mandibular condyle contralateral to the bolus. Oyen also diagrams
the lines-of-action of the masticatory muscles.
In Chapter 12, “Prenatal Facial Growth
and Development,” Enlow presents a wealth
of craniofacial embryology that both complements and supplements what most students
learn in the standard medical school course.
Enlow builds on the textbook discussion of
pharyngeal arches and pouches by tracking
the origin of major craniofacial structures
and functional regions. This chapter ends
with a diagrammatic comparison of remodelling patterns of the pre- and postnatal skull.
M. M. Cohen’s chapter on craniofacial
“Anomalies, Syndromes, and Dysmorphic
Growth” has very brief coverage of the more
common craniofacial congenital abnormalities. Plastic surgeons will of course go elsewhere for more complete discussion.
Next, W. W. Merow and B. H. Broadbent,
Jr. contribute a useful but narrow chapter on
craniometry. It centers on comparisons of
lateral and frontal X-rays taken with the
Broadbent-Bolton cephalometer. Since the
1920s this head registration technique has
been used to study different individuals comparatively and single individuals through
time. About 5000 children were X-rayed a t
regular intervals in this way by the Brush
and Bolton studies of the 1930s and 1940s.
Lines, linear measurements, planes, and angles have all been traced from these X-rays.
The discussion concludes with the Bolton
standards for comparison of frontal and lateral head X-rays published by Broadbent,
Broadbent, and Golden in 1975. It is unfortunate that more recent Broadbent-Bolton
based studies, such a s those of Behrents
(reported in Chapter 16) or Richtsmeier
(1985), are not discussed. Also, a report on
the Broadbent-Bolton research program
alone, while important, hardly does justice to
the overall field of cephalometrics. Completely unmentioned are the advances since
the mid-1980s achieved through computerbased data capture (Vannier and Conroy,
1989) and analysis (Rohlf, 1990).
R. G. Behrents’ chapter on the unusual
subject of adult facial growth reports on age
changes found in follow-up X-rays of 163 of
the original Bolton study participants. Unexpectedly, bony craniofacial dimensions
were found to increase 2-10% after “maturity”(between ages 17 and 83).In late adulthood vertical dimensions changed most,
which is consistent with known soft tissue
Enlow uses the last two chapters to
present basic research, much of it his own.
Chapter 17, “Facial Growth and Development in the Rhesus Monkey,” is a summary
of his well known comparative look at remodelling patterns in rhesus macaques and humans. The last chapter, “Bone and Cartilage,” is primarily a histological justification
for earlier statements on the “macrobehavior” of these tissues.
In sum, this books strengths come from
Enlow’s broad background and participant
status in the debate over craniofacial morphogenesis. Granted, craniofacial clinicians
will have to look elsewhere for detailed information on congenital syndromes and students of craniofacial morphometrics will also
need to find additional material. In all, “Facial Growth” is a must read for surgeons and
anyone else interested in craniofacial biology.
Department of Anthropology
Graduate School
City University of New York
New York, New York
Richtsmeier J T (1985) A study of normal and pathological craniofacial morphology and growth using finite
element analysis. PhD thesis, Northwestern University, Evanston.
Rohlf J (1990) Morphometrics. Annu. Rev. Ecol. Syst.
Vannier MW, and Conroy GC f 1989) Imaging workstations for computer-aided primatology: Promises and
pitfalls. Folia Primatol. 53:7-21.
making in the archaeological record. To do
By Steven J. Mithen. this, the author examines European MesoCambridge: Cambridge University Press. lithic faunal material and microliths, as well
1990. xii + 289 pp. $59.50 (cloth).
as Upper Paleolithic art and faunal assemblages. Simulation models and ethnographic
Thoughtful Foragers is a product of the analogy are the interpretive tools applied to
theoretical school of archaeology at Cam- the prehistoric data.
bridge University that has been emerging
Mithen provides a valuable service in
and moving into the forefront in the past 20 stressing the importance of individual choice
years. In keeping with the traditions initi- in prehistory. We do need to be reminded of
ated by Grahame Clark and Eric Higgs, this this, despite the recognized effects of powermodern theoretical school is strongly ori- ful historic figures and of individuals in the
ented toward paleoecology, with the recent events depicted in our daily newspapers.
addition of middle range theory.
However, retrieving evidence of significant
Thoughtful Foragers is a book with a n individual decisions from the archaeological
intriguing and provocative title, written in a record is a greater challenge than observing
sophisticated, yet sometimes arduous man- contributions of living persons. Two things
ner. The goal set out in the introductory reduce the visibility of individuals in prehischapter is to identify individual decision tory-the anonymity of most prehistoric peo-
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saunders, 1990, facial, growth, 576, enlow, 3rd, philadelphia
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