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scores were compressed into seven phases, each with a given range, mean, and median age
(
Buckberry and Chamberlain, 2002
).
Shortly following the
Buckberry and Chamberlain (2002)
paper,
Osborne et al. (2004)
tested the
Lovejoy et al. (1985a)
method on a modern sample from the Robert J. Terry
Anatomical Skeletal Collection
8
and William M. Bass Donated Skeletal Collection
9
and
found that only 33% of the individuals were correctly aged using the original 5 year age
ranges. An analysis of covariance (ANCOVA) found that age was the only significant influ-
ence on auricular surface morphology. Therefore, age assessment of the auricular surface
does not need to account for different ancestral groups or sexes. “Collection” was included
as a variable in the ANCOVA but was not significant, indicating that secular change (changes
in morphology in populations over time) has not affected the morphological indicators of the
auricular surface in the United States during the last century.
10
Osborne et al. (2004)
advise
that six phases (
Figure 3.3
), not the original eight (
Lovejoy et al., 1985a
) or revised seven
(
Buckberry and Chamberlain, 2002
), should be used. However, Osborne et al.'s method
has not caught on in practice (
Garvin and Passalacqua, 2012
), possibly because each phase
is associated with large age ranges.
The Sternal Extremity of the Rib
While
I¸can et al. (1984a,b)
are most often credited with the development of aging of the
sternal extremity of the rib, this indicator was actually noted earlier in print by
Kerley (1970),
Semine and Damon (1975), Ubelaker (1978)
, and
McCormick (1980)
. McCormick was
a pathologist and during his study of cadaver specimens, he noticed a positive relationship
between the amount of mineralization in the costal cartilages on radiographs and known age-
at-death. His study of over 200 cadavers confirmed this finding as a means to assess age-at-
death broadly. However, this preliminary article only discussed broad changes and “does not
allow the degree of precision that can be obtained by experts experienced in the evaluation of
skeletal remains” (
McCormick, 1980
:740).
Currently, most anthropologists employ the technique described by
I¸can et al. (1984a,b)
.
Expanding on the work of
Kerley (1970)
and
Ubelaker (1978), I¸can et al. (1984a,b)
described
changes in three components of rib morphology: (1) pit depth, (2) pit shape, and (3) rim wall
and configurations of the ribs of EuropeanAmericanmales. I¸can and colleagues first analyzed
the right fourth rib of 118 EuropeanAmericanmales autopsied at the Broward CountyMedical
Examiner's Office, Fort Lauderdale, Florida. Eight phases were developed based on age-
related changes, including the formation, depth, and shape of a pit, the configuration of the
walls and rim around the pit, and the overall texture and quality of the bone. See
Figure 3.4
.
Based on observed sexual dimorphism in other studies of the ribs,
I¸can et al. (1985)
pub-
lished different standards for European American females. Similar to their earlier study, ribs
were seriated and eight phases were developed based on morphological changes. Unlike the
male sample, where morphological changes did not occur until at least 17 years of age, the
8
Curated by the National Museum of Natural History at the Smithsonian Institution, Washington, D.C.
9
Curated by the Forensic Anthropology Center at the University of Tennessee, Knoxville, Tennessee.
10
Refer to Moore and Ross (Chapter 6) and McKeown and Schmidt (Chapter 12), this volume for further
discussion on secular change.
