AGE ESTIMATION

OF THE
HUMAN SKELETON
 AGE ESTIMATION OF
THE HUMAN SKELETON
Edited by

KRISTA E. LATHAM, PH.D.

and

MICHAEL FINNEGAN, PH.D., D-ABFA

With a Foreword by

Stanley Rhine, PH.D., D-ABFA

University of New Mexico
 Published and Distributed Throughout the World by

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ISBN 978-0-398-07949-9 (hard)

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Library of Congress Cataloging in Publication Data

Age estimation of the human skeleton / edited by Krista E. Latham, Ph.D. &
Michael Finnegan, Ph.D., D-ABFA, with a foreword by Jane E. Buikstra,
Ph.D., D-ABFA and Stanley J. Thine, Ph.D., D-ABFA.
p. cm.
Includes biographical references and index.
ISBN 978-0-398-07949-9 (hard)—ISBN 978-0-398-07950-5 (pbk.)
1. Human skeleton—Analysis. 2. Human skeleton—Growth. 3. Human body—
Composition—Age factors. 4. Forensic athropology. 5. Forensic osteology. 6.
Dental anthropology. I. Latham, Krista E. II. Finnegan, J. Michael. III.
Buikstra, Jane E. IV. Rhine, Stanley, V. Title.

GN70.A34 2010
614’17—dc22 2010016116
 To the memory of:
Alice M. Brues (1913–2007)
and
Sheilagh T. Brooks (1923–2008)
 CONTRIBUTORS

JEREMY J. BEACH, M.S.

Purdue University, Department of Anthropology
700 West State St., Suite 219
West Lafayette, IN 47907
beachj@purdue.edu

CARRIE A. BROWN, M.A.

Joint POW/MIA Accounting Command Central Identification Laboratory
310 Worchester Ave., Bldg. 45
Hickam AFB, HI 96853-5530
carrie.brown@jpac.pacom.mil

AMBER R. CAMPBELL HIBBS, M.A.

Emory University, Department of Anthropology
1557 Dickey Dr.
Atlanta, GA 30322
amber.rae.campbell@gmail.com

CHRISTIAN CROWDER, PH.D., D-ABFA

Deputy Director of Forensic Anthropology Office of Chief Medical Examiner
520 First Ave.
New York, NY 10016
ccrowder@ocme.nyc.gov

JANENE M. CURTIS, M.S.

Forensic Identification Services, RCMP K Division HQ
11140 109 St.
Edmonton, AB, Canada T5G 2T4
jmcurtis11@hotmail.com

vii
viii Age Estimation of the Human Skeleton

MICHAEL FINNEGAN, PH.D., D-ABFA

Osteology Laboratory Professor, Department of Sociology, Anthropology and Social Work
204 Waters Hall, Kansas State University
Manhattan, KS 66506
finnegan@ksu.edu

HEATHER M. GARVIN, M.S.

Johns Hopkins School of Medicine, Center for Functional Anatomy & Evolution
1830 E Monument St.
Baltimore, MD 21205
heamarie@jhmi.edu

JENNIFER L. HARMS-PASCHAL, M.S.

Clinical Data Manager
7551 Metro Center Dr.
Austin, TX 78744
jennpaschal@gmail.com

CAROLYN V. HURST, M.A.

Michigan State University, Department of Anthropology
354 Baker Hall
East Lansing, MI 48824
hurstcar@msu.edu

ANGIE HUXLEY PH.D., D.O.

St. Joseph’s Hospital and Medical Center, Department of Internal Medicine
350 W. Thomas Rd.
Phoenix, AZ 85013
akhuxley@pol.net

DUSTIN M. JAMES, B.A.

Department of Anthropology, University of Memphis
316 Manning Hall
Memphis, TN 38152
dmjames1@memphis.edu

KRISTA E. LATHAM, PH.D.

Assistant Professor of Biology & Anthropology, Research Associate, University of Indianapolis
Archeology & Forensics Laboratory
1400 East Hanna Ave.
Indianapolis, IN 46227
lathamke@uindy.edu
 Contributors ix

STEPHEN P. NAWROCKI, PH.D., D-ABFA

Sease Distinguished Professor of Forensic Studies, Professor of Biology & Anthropology
Director, Graduate Human Biology Program, Co-Director, University of Indianapolis
Archeology & Forensics Laboratory
1400 E. Hanna Ave.
Indianapolis, IN 46227
snawrocki@uindy.edu

NICHOLAS V. PASSALACQUA, M.S.

Michigan State University, Department of Anthropology
354 Baker Hall
East Lansing, MI 48823
passala5@msu.edu

SUSAN PFEIFFER, PH.D.

University of Toronto Professor, Anthropology Department
19 Russell St.
Toronto, ON, M5S Canada 2S2
susan.pfeiffer@utoronto.ca

CHRISTOPHER W. SCHMIDT, PH.D.

Indiana Prehistory Laboratory Associate Professor, Department of Anthropology,
University of Indianapolis
1400 E. Hanna Ave.
Indianapolis, IN 46227
cschmidt@uindy.edu

RACHEL A. SHARKEY, B.S.

University of Indianapolis, Department of Anthropology
1400 East Hanna Ave.
Indianapolis, IN 46227
lockhartra@uindy.edu

EMILIE L. SMITH, M.S., M.P.A.S., P.A.-C.

Board Certified Physician Assistant,
University of Texas Health Science Center at San Antonio
3537 County Rd. 4220
Commerce, TX 75428
els711@gmail.com
x Age Estimation of the Human Skeleton

MARGARET STREETER, PH.D.

Associate Professor, Department of Anthropology, Boise State University
1910 University Dr.
Boise, ID 83725
margaretstreeter@boisestate.edu

KYRA E. STULL, M.S.

Coordinator, Forensic Anthropology Center, Department of Anthropology
Texas State University - San Marcos
601 University Dr., ELA 232
San Marcos, TX 78666
ks47@txstate.edu

DOUGLAS H. UBELAKER, PH.D., D-ABFA

Department of Anthropology, Smithsonian Institution
NMNH, MRC 112
Washington, DC 20560-0112
ubelaked@si.edu

NATALIE M. UHL, M.S.

Department of Anthropology, University of Illinois at Urbana-Champaign
109 Davenport Hall, 607 S. Mathews Ave.
Urbana, IL 61801
uhl1@illinois.edu

DIANA M. WILBERT, B.S.

Department of Sociology, Anthropology and Social Work
204 Waters Hall, Kansas State University
Manhattan, KS 66506
 FOREWORD

n ascertaining that a set of remains are both human and of medicolegal signifi-
I cance, the forensic anthropologist absorbs many impressions. These form an
instant conclusion, a skeletal gestalt. However, most practitioners agree that creation
of a biological profile should be undertaken in a very compartmentalized fashion,
independently assessing sex, age, ancestry and stature. Later, one can more fully
evaluate other attributes; ante-, peri- and postmortem trauma, state of health and
other idiosyncratic features that might be useful in narrowing down the search for
identity, and for attributes that would illuminate time since death, cause of death and
other matters of medicolegal interest.
Aging younger individuals has traditionally depended upon an assessment of the
maturation of the skeleton; the appearance of centers of ossification, epiphyseal
fusion, development and eruption of the teeth, and in the very young, direct meas-
urement of the bony elements. In older individuals the age estimation process has
focused on degeneration of the skeleton as reflected in various joints of the body,
such as the pubic symphysis, auricular surface and cranial sutures. Each of these con-
tinues to be the focus of ever-closer analytical scrutiny.
In the past few decades there has been a growing interest in assessing age by an
analysis of the fine structure of bones and teeth. It may seem that this continued finer
focus provides an alternate, more exotic, hardware-dependent and time-demanding
analysis. Yet, not all of these methods will be used on a single case. Instead, we have
an ever-expanding galaxy of potential approaches that can be selectively applied to
any case.
Clearly, no single criterion is adequate for estimating age. Any estimate of age (or
any other quality) is made more reliable and accurate by employing multiple
approaches with multiple bones. While age may be estimated from the state of the
pubic symphysis (for example), it is dangerous to place all of one’s eggs in that—or
any other—single basket. Evaluation of multiple bones through a combination of
anthropometric, anthroposcopic and histological means offers convergent conclu-
sions from methodologically independent sources, and thus the most robust results.

xi
xii Age Estimation of the Human Skeleton

This volume effectively illustrates that the study of human osteology in a forensic
context continues to become both wider and deeper.

STANLEY RHINE
 INTRODUCTION

ge Estimation of the Human Skeleton represents a collection of some of the latest

A research in age at death estimation indicators of human skeletal remains using
dental, gross morphological, histological and multifactorial techniques. The papers
represent scientific research that has been conducted and presented at scientific
forums within the past several years, and encompasses age estimation methods from
all life-stage categories, including: fetal, subadult, and adult. This book will serve as
a convenient starting point for practical and research applications.

INSPIRATION FOR THE VOLUME

This volume arose from various symposia at recent Mountain, Desert and Coastal
Forensic Anthropologists meetings, focusing on methods of age estimation from the
human skeleton. The symposia were organized by the editors, who noticed a great
deal of research being conducted on this topic. The editors also recognized a need
for an up-to-date book on aging human skeletal remains, as the last text available for
this purpose was compiled in 1989, and significant scientific advances have been
made since that time. There are several books available that have one or two chap-
ters devoted to skeletal aging techniques. However, the full spectrum of techniques
cannot be covered in one or two chapters and an entire volume on this topic is need-
ed.

THE MOUNTAIN, DESERT AND COASTAL

FORENSIC ANTHROPOLOGISTS

The Mountain Desert & Coastal Forensic Anthropologists meeting (MD&C) cele-
brates its thirtieth anniversary in 2010. From the beginning, MD&C has served as a
forum to foster the presentation of new research and a continuing discussion of per-
tinent topics surrounding skeletal biology and forensic anthropology. This volume
celebrates that legacy.

xiii
xiv Age Estimation of the Human Skeleton

Looking Back
MD&C officially met for the first time in 1981 with nine attendees at the Southern
Utah State College’s mountain cabin. The first three meetings focused on regional
variation of human skeletal remains, and resulted in the first MD&C inspired publi-
cation: Skeletal Attribution of Race (Gill and Rhine, 1990). These early accommoda-
tions were very rustic and remote, a combination that kept attendee numbers small
and meetings very informal.
The MD&C meeting location changed to the Lake Mead Lodge in Boulder City,
Nevada in 1986. With the change of venue came more attendees and the need for
more organization. By 1988 the number of attendees rose to 41 and by 1989 MD&C
had its first official schedule of presentations and first annual t-shirt. In 1991, The
Connective Tissue became the official journal of the Mountain, Desert and Coastal
Forensic Anthropologists.
The silver anniversary of MD&C was celebrated in 2005 with 37 attendees. By
this time the atmosphere had shifted to a more balanced group of forensic anthro-
pologists and eager students. The number of individuals wanting to present new or
refined research grew to the point that a moderator was required to keep track of
time. The Lake Mead Lodge closed its doors in 2008, and MD&C had to move to
yet another location in Boulder City. Younger attendees try to maintain the original
intent of the MD&C founders, while adapting to changing times. As attendee num-
bers rise and fall from year-to-year, one thing remains the same: MD&C is a favorite
meeting for many anthropologists (historical information summarized from various
volumes of The Connective Tissue).

Looking Ahead
MD&C was created as a way to gather forensic anthropologists and their
advanced graduate students from the mountain, desert and coastal western part of
the United States together in a friendly informal atmosphere to discuss the field of
forensic anthropology. As attendee numbers have grown and demographics have
changed, so has the face of the meeting. However, MD&C remains consistent in
bringing out the best in its attendees. MD&C is distinct from other meetings with its
informal attire and no titles attitude. This creates an environment where old and
young, experienced and naive, debate and share ideas. A glance at regular attendees
of the past and present reveal a long list of able-bodied forensic anthropologists. The
first 30 years of MD&C have inspired numerous researchers and two volumes, and
it is expected that there is still much to come.

K.E.L.
 Introduction xv

REFERENCES

Gill, G. W., & Rhine, S. (Eds.). (1990). Skeletal attribution of race. Albuquerque, New
Mexico: Maxwell Museum of Anthropology Anthropological Papers No 4.
Finnegan, M. (Ed.). (2000). The connective tissue 16(1). Manhattan, Kansas.
Finnegan, M. (Ed.). (2001). The connective tissue 17(4). Manhattan, Kansas.
Finnegan, M. (Ed.). (2002). The connective tissue 18(4). Manhattan, Kansas.
Finnegan, M. (Ed.). (2005). The connective tissue 21(2). Manhattan, Kansas.
 A HISTORY OF METHODOLOGY
IN THE ESTIMATION OF AGE AT
DEATH FROM THE SKELETON

D OUGLAS H. U BELAKER

he history of the methodology of estimating age at death from the human skele-
T ton is complex and incorporates a large and diverse literature. Given the limit-
ed space available for this section, I have chosen to focus only on key thematic
developments as presented in landmark synthetic works. Special attention is devot-
ed to the development of approaches based on newly recognized anatomical areas
and perspective, which continued to influence research in later times. This approach,
by necessity, limits literature coverage and indicates that some key individual stud-
ies are not examined exhaustively.

THOMAS DWIGHT’S PIONEER STUDIES

The work of Thomas Dwight (1843–1911) represents a useful entry point into the
history of age at death estimation. T. D. Stewart (1901–1997) considered him to be
the “father of forensic anthropology in the United States (Stewart, 1979, xii) since he
became involved in forensic cases and made significant early contributions to the
field. Working in Boston, Dwight conducted research and taught anatomy for
decades, holding the Parkman Professorship of Anatomy at Harvard. Although he
made significant research contributions to methods of age estimation (Dwight, 1881,
1890a,b) his reputation in forensic anthropology became established through his key
prize-winning publication in 1878 The Identification of the Human Skeleton, A Medico-
Legal Study. Given its historical prominence, this essay presents a useful platform to
launch this examination of the history of age estimation.
Although Dwight’s essay was general in nature, it addressed key points in age esti-
mation that continue in importance today. Much of the most relevant discussion is
presented in Chapter IV (Dwight’s volume) entitled “The Age.” In his introduction

xvii
xviii Age Estimation of the Human Skeleton

to this chapter, Dwight noted that age can “rarely be given with any great accuracy”
(Dwight, 1878:36). He highlighted the importance of sex difference in aging and that
different methods apply to different general stages of life. Dwight recognized an
immature stage up to age 25 in males and 22 in females, a young adult stage extend-
ing to about age 30, a mature stage from 30 to 60 and the “senile” stage “which may
begin at a very variable period” (Dwight, 1878:37). For the immature stage, he
stressed bone size and epiphyseal union, noting differences between beginning and
final fusion and recognizing considerable variation in the timing of development.
Dwight was so impressed with the likely variation that he refused to put these data
in tabular form noting “The fact is, that the careful observations of some hundreds
of skeletons of known ages, needed to settle this point, are yet to be made” (Dwight,
1878:37–38). This attitude contrasts with views presented in various anatomy texts of
the time and such a cautious approach likely contributed to the honor Stewart later
bestowed upon him.
Dwight also called attention to age changes in his young adult, mature, and senile
stages, but was similarly concerned that variation was extensive and solid research
needed to be completed. In a cautionary statement regarding cranial suture closure,
which was later overlooked by others, he noted “the closure of the sutures which usu-
ally begins in the mature stage is another of those signs that are too variable to be
depended on” (Dwight, 1878:38). He also cautioned of the variability in third molar
eruption “they are like the trains of some railroads, due when they arrive” (Dwight,
1878:39).
In summary, Dwight’s essay departed from texts of the time and likely won the
award and Stewart’s praise not because of the wealth of dogma, but because he
called attention to how little was really known about variation in age progression and
the need for research.

H. H. WILDER (1890–1971)

A professor at Smith College in Massachusetts, Wilder’s name is closely linked

with methodology relating to personal identification issues, including facial approx-
imation. Trained as a zoologist in Europe, he became involved in forensic issues late
in his career and coauthored a key synthetic work on personal identification (Wilder
and Wentworth, 1918). Although much of Wilder’s volume focuses on fingerprint
analysis and other aspects of soft tissue identification, it contains a robust section
entitled “identification of fragmentary, decomposed or dried remains; identification
of bones and teeth.” This particular section (Chapter VI in Wilder’s volume)
includes summary information on age estimation that reveals developments in think-
ing by that time.
Like Dwight, Wilder called attention to variation but was much more willing to
offer specifics for age changes in bones and teeth. According to Wilder “the age of a
 A History of Methodology xix

person under twenty-five may be quite definitely calculated from the skeleton, or
even, occasionally, from a single bone” (1918:85). The Wilder and Wentworth pub-
lication (1918:87) provides a chart listing the fusion of the coracoid process of the
scapula with the “main bone” at puberty, fusion of the basilar synchondrosis at the
16th year, fusion of the “three parts of the os innominatum” by the 18th–20th year
and fusion of the iliac crest by the 25th–28th year. Dental eruption is discussed but
not dental formation. Criteria for estimating age in the adult years focuses on oblit-
eration of the cranial sutures, shifts in the mandibular angle and “the reduction of the
angle between the neck, and shaft of the femur” (Wilder and Wentworth, 1918:88).
Wilder does not discuss the database that such opinions are based upon and fails to
echo Dwight’s cautionary appeals for additional research.

HRDLIČKA’S “ANTHROPOMETRY” (1920)

Although Aleš Hrdlička (1869–1943) was known primarily for his contributions to
other areas of anthropology (Stewart, 1940), he also made significant and pioneering
efforts in forensic applications (Ubelaker, 1999). In an early synthetic work, which
became a standard reference work for practicing physical anthropologists, Hrdlička
(1920) addressed age estimation from skeletal remains. In this work, Hrdlička sum-
marized basic age changes discussed by others above but stressed factors which in
his considerable experience were especially useful. For the early adult years he
emphasized the regularity of fusion of the basilar synchondrosis and reported age
ranges of one to five years for complete fusion at various bone sites. He called atten-
tion to population variation in the timing of tooth eruption and dental wear. Hrdlička
noted the age changes in cranial suture closure and suggested that considering suture
closure and dental wear together, “we may correctly estimate the age of the adult
subject to within, perhaps, ten years” (1920:99).
Hrdlička also noted “the pubic articulation shows important changes with age”
(1920:98). Although no detail is provided, he cited a recently published study by T.
Wingate Todd (1885–1938) “Age changes in the Pubic Bone” (1920) in the American
Journal of Physical Anthropology. Since Hrdlička was editor of that journal at the time,
he likely had an early exposure and positive impression of the content in that key
article. This seminal article by Todd resulted from the then recent assemblage of
anatomical collections of known age at death at the Anatomical Laboratory of
Western Reserve University in Cleveland, Ohio, and set the stage for later develop-
ments in age estimation from the pubic symphysis.
Hrdlička’s Practical Anthropometry published in 1939 presents a revised version of
his 1920 publication and a glimpse at the minimal developments in age estimation
methodology in the intervening 19 years. This version differs little from the previous
volume, but provides a more specific guide to age changes in dental attrition. The
previously mentioned quote in regards to age estimation from cranial sutures and
xx Age Estimation of the Human Skeleton

dental observations was modified to suggest an accuracy of “within less than ten
years” (1939:47). For detail on recent research developments, Hrdlička refers read-
ers in a footnote to publications by Todd (1930) on the pelvis and Graves (1922) on
the scapula. Hrdlička also called attention to the importance of osteophytosis in age
evaluation but presented no detail.

KROGMAN’S “GUIDE” (1939)

Historians of forensic anthropology (e.g., Stewart, 1979) have identified Wilton

Marion Krogman’s 1939 publication as a key development in the field. For the first
time, Krogman (1903–1987) assembled important information on human identifica-
tion from skeletal remains for publication in an outlet oriented toward law enforce-
ment. The publication revealed to that community the value of scientifically-orient-
ed analysis of human skeletal remains in the identification process. Although much
of the general information is presented in a manner similar to publications by
Hrdlička and others cited above, Krogman presented greater detail. He presented
age information on different stages of cranial suture closure (begin, rapid, final) and
added information on the dates of appearance of ossification centers.
In contrast to Hrdlička’s publications, Krogman presented considerable detail on
age changes at the pubic symphysis. He called attention to the gradual loss of bil-
lowing on the symphyseal face as well as the formation of “nodules,” pitting and ero-
sion. Krogman also noted how the use of x-rays could be valuable, highlighting
changes seen in four stages of below 25 years, between 26 and 39, between 40 and
55 and over 56 years. Since the text is not referenced, it is not clear if Krogman’s
information was derived from the literature and/or from his own research.

STEWART’S EDITION OF HRDLIČKA’S

PRACTICAL ANTHROPOMETRY (1952)

Following Hrdlička’s retirement and death, T. D. Stewart published a revision of

the classic reference work Practical Anthropometry. Although he kept Hrdlička’s name
in the title, Stewart put his own mark on the volume by significantly updating much
of the information. Changes were minimal in the skeletal aging section with the most
significant addition being a footnote calling attention to the then recent publication
(1950) of the Radiographic Atlas of Skeletal Development of the Hand and Wrist by Greulich
and Pyle.
 A History of Methodology xxi

MCKERN AND STEWART’S SKELETAL AGE

CHANGES IN YOUNG AMERICAN MALES (1957)

In 1954, T.D. Stewart traveled to Kokura, Japan to participate in a military iden-

tification effort of United States soldiers killed during the Korean conflict. Data on
various skeletal age changes were collected during the identification process on 450
young American males. These data later became the basis for the classic monograph
published in 1957. In assembling these data, Stewart recognized the need for infor-
mation derived from new samples in order to capture information on the vast range
of human variation. He also recognized the existing paucity of data on relatively
young individuals since most of the available anatomical collections were comprised
of older adults. Stewart also suspected that most of the reported age ranges for vari-
ous skeletal indicators were too restricted and did not take adequate account of the
range of variation and the various stages of development and expression of the traits
examined. The military sample offered a partial remedy to many of these issues.
Although the study was restricted to males, it represents an historical leap forward
in that it examined age changes in greater detail than had been the case previously.
For example, observations on cranial suture and epiphyseal closure were broken
down into individual sutures and epiphyses and by four stages of closure (in addition
to no closure). This approach yielded unique data on age variation in closure as well
as information on population variation.
In their treatment of the pubic symphysis, McKern and Stewart decided to aban-
don the typological approach advanced earlier by Todd (1920, 1921) in favor of a
more dynamic formula process. The authors were impressed with the approach
taken by William Herbert Sheldon (1898–1977) in his efforts to study human phys-
ique. Sheldon’s (1940) somatotype formula utilized three components of seven
grades to characterize individual body type. Incorporating a simplified version of
this concept, McKern and Stewart settled on the three component, five-subdivision
system that was eventually published and widely utilized. This system recognized
that the various components of the symphyseal face do not always occur in the same
pattern and sequence as suggested by the Todd system.

KROGMAN’S THE HUMAN SKELETON IN FORENSIC MEDICINE (1962)

This classic text represents the first major synthesis of methodology in age esti-
mation. Although the volume covered many aspects of forensic anthropology, 93
pages were devoted to the estimation of age at death. In contrast to his 1939 publi-
cation, the 1962 volume is very well referenced, so much so that it is difficult to sep-
arate Krogman’s own data and opinions from the compilation from the literature.
Reflecting his career interest in growth and development, the section on “the earlier
years” is uniquely comprehensive for its time, presenting detailed information on
xxii Age Estimation of the Human Skeleton

bone formation and a summary of the already complex literature on epiphyseal for-
mation and closure. Absent from this section is information on dental development
and eruption, keeping with the emphasis on the “skeleton” implied in the title.
Although little totally new information is presented in the text, it presents for the first
time an exhaustive survey of the published literature with insightful commentary
from a very experienced practitioner.
Krogman dedicated the book to T. Wingate Todd “with whom I studied and from
whom I learned.” Thus it is not surprising that Todd’s work is prominently present-
ed in the volume. He presented both the Todd, and McKern and Stewart systems of
assessment of the symphysis pubis, but commented “with the basic work of Todd and
the refinements introduced by Brooks and by McKern and Stewart, the pubic sym-
physis takes it place as the most reliable indicator of age in the human skeleton”
(1962:105). Although Krogman provides considerable discussion of variation of age
indicators, much of the data presented seem to be overly concise even by standards
of the time. He concludes the aging sections with the statement referring to the third
and fourth decades “using pubic symphysis plus other skeletal criteria, I’d venture
an accuracy of plus or minus two years” (1962:111).

STEWART’S ESSENTIALS OF FORENSIC ANTHROPOLOGY (1979)

As with Krogman’s 1962 volume, a major segment (62 pages) of Stewart’s syn-
thetic volume focused on methodology relating to the estimation of age at death. In
contrast to the Krogman volume, Stewart included a carefully selected literature
review, which reflected his sense of the most appropriate techniques available. In
addition to the approaches to immature age estimation included in the Krogman vol-
ume, Stewart added a robust discussion of dental formation and eruption, noting the
importance of teeth in age estimation of the young.
For adult estimation, Stewart included the then recent study of Gilbert and
McKern (1973), which extended the McKern and Stewart system of evaluating the
pubic symphysis to females. He also provided detail from the literature and his own
research on arthritic type change in joints, histological dental approaches, studies of
change in cancellous tissue, and bone microstructure including Ellis R. Kerley’s
(1924–1998) studies of age changes in histological features of compact bone (Kerley,
1965, 1969, 1970). The volume is distinctive from previous works in: (1) producing
methodology focusing on a broader range of anatomical structures, (2) increasing
awareness of variation in most age changes, and (3) the need to be selective in con-
sulting the supportive published literature.
 A History of Methodology xxiii

SUMMARY

In this survey of historical developments in methodology to estimate age at death

from skeletal remains several trends are apparent. The most obvious development is
the gradual recognition through research that different areas of the skeleton convey
distinct information on age change. For adults, the early reliance on dental attrition
and cranial suture closure gradually shifted as new techniques came on line. While
evaluation of the pubic symphysis barely was discussed in Hrdlička’s time, it gradu-
ally began to dominate adult age estimation with later research efforts by Todd,
McKern and Stewart, and Gilbert and McKern. Clearly the discussion of histologi-
cal methods, which are so prominently featured in Stewart’s 1979 volume, were not
on the radar screen of earlier synthesizers.
Another clear development is the gradual recognition of the importance of varia-
tion in age estimation and its resulting impact on error. In hindsight, modern foren-
sic anthropologists likely would consider the very early attempts at age estimation to
be overly precise with insufficient recognition of the actual error involved. This early
naïve precision was a product of the available data and lack of research on samples
of more diverse origins and of greater age range. Gradually such research has been
conducted with the growing perception of human variation in most of the attributes
developed.
Another trend apparent in the literature examined here is the increasing aware-
ness of the need for additional research and access to larger and more diverse sam-
ples. While Dwight recognized aspects of this need, real progress had to await the
acquisition of suitable samples of individuals of known age at death. Such samples
were gradually assembled either by the careful curatorial efforts of anatomists such
as T. Wingate Todd or the more opportunistic data collection by T. D. Stewart in his
human identification efforts.
An additional recognizable pattern involves more complex and sophisticated
methodology. Approaches have a growing tendency to recognize that different
methods are more appropriate and effective for different age ranges. Increasingly,
methodology calls for combining different approaches with the realization that com-
bined approaches are frequently more effective than isolated ones.
Although these developments play prominent roles in the history outlined here,
they do not stop with Stewart’s 1979 synthesis. These trends continue into more
recent periods and play dominant roles in the material presented in this volume.
Existing efforts to improve methodology in the estimation of age at death build on
the accomplishments and revelations of past initiatives. Many of the developments
recognized as being important by our academic ancestors remain key today.
xxiv Age Estimation of the Human Skeleton

REFERENCES

Dwight, T. (1878). The identification of the human skeleton. A medico-legal study. Boston: David
Clapp & Son, Printers.
Dwight, T. (1881). The sternum as an index of sex and age. Journal of Anatomy and Psysiology
15:327–330.
Dwight, T. (1890a). The sternum as an index of sex, height and age. Journal of Anatomy and
Psysiology 24:527– 535.
Dwight, T. (1890b). The closure of the cranial sutures as a sign of age. Boston Medical and
Surgical Journal 122(17):389–392.
Gilbert, B. M., & McKern, T. W. 1973). A method for aging the female os pubis. American
Journal of Physical Anthropology 38(1):31–38.
Graves, W. W. (1922). Observations on age changes in the scapula. A preliminary note.
American Journal of Physical Anthropology 5(1):21–33.
Greulich, W.W., & Pyle, S.I. (1950). Radiographic atlas of skeletal development of the hand and
wrist. Stanford, CT: Stanford University Press.
Hrdlička, A. (1920). Anthropometry. Philadelphia: The Wistar Institute of Anatomy and
Biology.
Hrdlička, A. (1939). Practical anthropometry. Philadelphia: The Wistar Institute of Anatomy
and Biology.
Kerley, E. R. (1965). The microscopic determination of age in human bone. American Journal
of Physical Anthropology 23(2):149–163.
Kerley E. R. (1969). Age determination of bone fragments. Journal of Forensic Sciences
14(1):59–67.
Kerley, E. R. (1970). Estimation of skeletal age after about age 30. In: T. D. Stewart (Ed.),
Personal identification in mass disasters. pp. 57–70. Washington (D.C.): National Museum
of Natural History.
Krogman, W. M. (1939). A guide to the identification of human skeletal material. FBI Law
Enforcement Bulletin 8(8):3–31.
Krogman, W. M. (1962). The human skeleton in forensic medicine. Springfield, IL: Charles C
Thomas Publisher.
McKern, T. W., & Stewart, T. D. (1957). Skeletal Age Changes in Young American Males.
Natick (MA): Headquarters Quartermaster Research & Development Command,
Quartermaster Research & Development Center, Environmental Protection Research
Division. Technical Report EP-45.
Sheldon, W. H. (1940). The varieties of human physique: An introduction to constitutional psycholo-
gy. New York: Harper & Brothers Publishers.
Stewart, T. D. (1940). The life and writings of Dr. Aleš Hrdlička, 1869–1939. American Journal
of Physical Anthropology 26:3–40.
Stewart, T. D. (1952). Hrdlička’s practical anthropometry. Philadelphia: The Wistar Institute of
Anatomy and Biology.
Stewart, T. D. (1979). Essentials of forensic anthropology: especially as developed in the
United States. Springfield, IL: Charles C Thomas.
Todd, T. W. (1920). Age changes in the pubic bone. I. The Male White Pubis. American Journal
of Physical Anthropology 3(3):285–334.
 A History of Methodology xxv

Todd, T. W. (1921). Age changes in the pubic bone. II. Pubis of Male Negro-White hybrid.
American Journal of Physical Anthropology 4(1):1–70.
Todd, T. W. (1930). Age changes in the pubic bone: VIII Roentgenographic differentiation.
American Journal of Physical Anthropology 14(2):255–271.
Wilder, H. H., & Wentworth, B. (1918). Personal identification: Methods for the identification of
individuals, living or dead. Boston: Richard G. Badger, The Gorham Press.
Ubelaker, D. H. (1999). Human skeletal remains, excavation, analysis, interpretation (3rd ed.).
Washington (D.C.): Taraxacum.
 ACKNOWLEDGMENTS

he editors would like to acknowledge all those who have participated in the
T Mountain Desert and Coastal Forensic Anthropologists (MD&C) meetings over
the past thirty years. MD&C provides a forum for the presentation and discussion of
scholarly work in the field of forensic anthropology, and it was at MD&C that the
majority of these papers were originally presented and at which the inspiration for
this volume was realized.
We would like to extend our gratitude to Drs. Bruce Anderson, Jerry Melbye and
P. Willey for reviewing the material and providing feedback regarding the papers in
this volume, and to Amandine Eriksen for designing the cover illustration. Our
thanks to those individuals who assisted with the preparation of the volume, espe-
cially Elizabeth DeVisser, Elena Madaj, Megan Madonna and Imran Musaji. We
also wish to acknowledge the patience and support of our friends and family during
the preparation of this volume.
Finally, the editors would like to thank the contributors to this volume for their
hard work and efforts. It has been a pleasure working with you all over the past two
years. Our gratitude to Mr. Michael Thomas of Charles C Thomas Publisher, Ltd.
for his patience and assistance throughout this process.

xxvii
 CONTENTS

Page
Foreword by Stanley Rhine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi
Introduction by Krista E. Latham . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii
A History of Methodology in the Estimation of Age at
Death from the Skeleton by Douglas H. Ubelaker . . . . . . . . . . . . . . . . . . . . . . . . . . xvii

Chapter
SECTION 1: DENTAL AGING TECHNIQUES

1. Dental Aging Techniques: A Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Jeremy J. Beach, Christopher W. Schmidt & Rachel A. Sharkey
2. The Estimation of Age at Death through the
Examination of Root Transparency . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Jennifer L. Harms-Paschal & Christopher W. Schmidt
3. Age Estimation by Root Dentin Transparency
of Single Rooted Teeth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Amber R. Campbell Hibbs & Michael Finnegan
4. Age Estimation by Root Dentin Transparency of
Double Rooted Mandibular Molars . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Diana M. Wilbert & Michael Finnegan
5. Age Estimation of Subadult Remains from
the Dentition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Emilie L. Smith

xxix
xxx Age Estimation of the Human Skeleton

SECTION 2: OSTEOLOGICAL AGING TECHNIQUES

6. The Nature and Sources of Error in the Estimation

of Age at Death from the Skeleton . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Stephen P. Nawrocki
7. Applications of the Human Sacrum in Age at
Death Estimation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
Nicholas V. Passalacqua
8. Limitations of Cartilage Ossification as an Indicator
of Age at Death . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Heather M. Garvin
9. Determination of Age at Death using the Acetabulum
of the Os Coxa . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134
Kyra E. Stull & Dustin M. James
10. Estimation of Age from Fetal Remains . . . . . . . . . . . . . . . . . . . . . . . . . . 147
Angie K. Huxley
11. Revisiting McKern and Stewart (1957): A Comparison
of Pubic Symphysis Methods at the JPAC/CIL . . . . . . . . . . . . . . . . . 161
Carrie A. Brown
12. Recent Advances in the Estimation of Age at Death
from the Assessment of Immature Bone . . . . . . . . . . . . . . . . . . . . . . . 177
Douglas H. Ubelaker

SECTION 3: HISTOLOGICAL AND

MULTIFACTORIAL AGING TECHNIQUES

13. The Application of Cortical Bone Histomorphometry

to Estimate Age at Death . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193
Christian Crowder & Susan Pfeiffer
14. Skeletal Aging Using Frontal Bone
Histomorphometrics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216
Janene M. Curtis & Stephen P. Nawrocki
15. Histological Age Estimation in Subadults . . . . . . . . . . . . . . . . . . . . . . . . 232
Margaret Streeter
16. Multifactorial Estimation of Age at Death from
the Human Skeleton . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243
Natalie M. Uhl & Stephen P. Nawrocki
 Contents xxxi

17. A Test of the Forensic Application of Transition

Analysis with the Pubic Symphysis . . . . . . . . . . . . . . . . . . . . . . . . . . . 262
Carolyn V. Hurst

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273
AGE ESTIMATION
OF THE
HUMAN SKELETON
 Section 1

DENTAL AGING TECHNIQUES

 Chapter 1

DENTAL AGING TECHNIQUES: A REVIEW

J EREMY J. B EACH, CHRISTOPHER W. SCHMIDT, AND RACHEL A. S HARKEY

INTRODUCTION

etermining the age at death for skeletal remains has always been a pri-
D mary concern of the biological anthropologist and dental remains, in
particular, can play a central role in assessing the age of an individual. Teeth
are usually available to the anthropologist for the construction of a biological
profile because they are durable and preserve very well, even when other
aspects of the skeleton have long since decomposed. Their ubiquity in arche-
ological and forensic contexts has led to a plethora of literature regarding
dental aging techniques. This chapter provides a summary of some of those
techniques in an effort to assist biological anthropologists in distilling the vast
literature that currently exists, but, by no means constitutes an exhaustive
reporting of all techniques, regardless of their efficacy. Instead, we have cho-
sen to highlight some of the more useful approaches to aging teeth, both past
and present as the intended audience includes biological anthropologists, pro-
fessional and student, as well as those in forensic odontology and forensic
dental anthropology (e.g., Schmidt, 2008).
Usually, the first stage of any skeletal study is the determination of the bio-
logical profile, which minimally consists of the individual’s age, sex, and
ancestry. The indicators used to create the biological profile, of course,
depend on those anatomical landmarks that are present at the time of the
study. The fact that tooth enamel is nearly 100 percent mineral makes it an
extremely durable substance. The density of enamel also makes it quite
impervious to many taphonomic effects. As a result, tooth crowns are usual-

5
6 Age Estimation of the Human Skeleton

ly present for anthropological examinations. In addition, the root structures

of teeth are housed in the alveolar bone of the mandible and maxillae, which
protect them from degradation. Thus, entire dentitions are often available for
age determination.
Dental aging techniques can be broken down into two major categories.
The first of these categories is centered on the developmental changes that
occur to the human dentition while the teeth are growing and emerging into
the oral cavity, and the second involves the degenerative changes that occur
once the teeth have erupted and begin to wear down.

DEVELOPMENTAL AGING TECHNIQUES

Hard Tissue Formation

Tooth formation begins very early in the life of an individual. By six weeks
in utero tooth primordia are lining up along the margin of what will soon be
the embryonic mouth. These buds are derived from the same embryonic tis-
sues that make the skin, thus teeth are a function of both the skin and the
skeleton. Over time the cells in the buds make the shape of the tooth and
eventually enamel and dentin are placed down to form the crown and root,
respectively. Thus, a fetus that is no more than a few months old has dental
hard tissues present in both its upper and lower jaws. By the time a baby is
born, all of its deciduous crowns have either formed or are in the process of
forming, and even one adult tooth crown, that of the first molar, is in the ini-
tial stages of development.
Documenting the sequence of dental formation is an avenue of research
that has been greatly studied in the past, and of these earlier studies Moorrees
et al. (1963a, b) is probably the best known. This radiographic study looked
at the formation of both the coronal and radical portions of the permanent
dentition as well as the eventual apical closure. From these observations,
Moorrees and colleagues (1963a, b) came up with a standard rate and
sequence of formation that could be used to estimate age more precisely than
using eruption alone. The method involves scoring each tooth for its devel-
opmental stage, then comparing those scores to values representing a partic-
ular age. For example, a deciduous first incisor crown that is fully formed and
is recovered adjacent to a deciduous second incisor crown that is only three-
fourths complete is consistent with a single individual aging to less than 6
months old. But, if a complete deciduous second molar is found in associa-
 Dental Aging Techniques: A Review 7

tion with these two teeth, then suspicion might be raised that more than one
individual is present because deciduous molars usually do not complete their
formation until after the age of two. Thus, the analyst determines an MNI or
minimum number of individuals represented in any assemblage simply by
inventorying the teeth. Should a particular tooth be present more than once,
or should teeth of disparate developmental age be found commingled, the
dental inventory will show that more than one person is present.
The chronological development of dental hard tissues is not a uniform
process that is identical in all populations. Differences have been noted
between groups of different ethnic backgrounds (Harris and McKee, 1990;
Harris, 2007; Blankenship et al., 2007). In particular, Harris and McKee
(1990) noted that tooth mineralization of populations of African ancestry
from the American south maturated at a significantly faster rate than compa-
rable populations of European ancestry by about as much as 5 percent. This
is why it is so vitally important that the biological anthropologist be well
experienced and versed in how human variation is manifest in the human
skeleton and dentition. Improper application of dental aging techniques can
lead to inappropriate assessment of a biological profile.
The Demirjian (1973, 1976, 1980) technique of scoring dental maturity has
been frequently applied for aging individuals of unknown age within the
realm of forensic science (TeMoananui et al., 2008; Tunc and Koyuturk, 2008;
Rózylo-Kalinowska et al., 2008; Martin-de las Heras et al., 2008). The tech-
nique was intended as a measure of maturity of the dentition of younger indi-
viduals. Each tooth in the dentition is scored on an ordinal scale and from
these values a composite score is computed that represents the overall devel-
opmental state of the individual. While this approach has been valuable in
those instances where the dentition is complete, as Hillson (1996) points out,
this methodology is not applicable when some teeth are missing, as is the case
in certain archeological populations where tooth loss due to cavities or
extreme wear is common. Moreover, when the Demirjian technique was
applied to populations other than those with which Demirjian developed his
standard, it was found that the methodology tended to overestimate age
(Moananui et al., 2008; Tunc and Koyuturk, 2008; Rózylo-Kalinowska et al.,
2008).

Dental Eruption
Schour and Massler’s well-known 1941 and 1944 studies detail the eruption
sequences of the human dentition by establishing 22 eruption stages and their