Craniometric Variation in the Americas
ANN H. ROSS,1 DOUGLAS H. UBELAKER,2 AND ANTHONY B. FALSETTI1
Abstract Craniofacial variation is investigated in Latin America and the
Caribbean. The samples included in this study are two historic and one pre-
historic sample from Ecuador; prehistoric and modern Cuban samples; a pre-
historic Peruvian sample; two prehistoric Mexican samples and one contem-
porary admixed Mexican sample; a 16th/17th-century Spanish sample; and
Terry blacks. Biological distance is investigated using traditional craniomet-
rics by computing size and shape variables according to Mosimann and col-
leagues. This study shows that there is much biological variation within the
Americas.
Two key objectives in physical anthropology are to document the vast range of
human variation of past and present populations and to investigate the evolution-
ary and environmental forces responsible for phenotypic variation, which allows
one to address large-scale issues such as migration and expansion. The patterns of
human variation among geographic populations have been examined using genet-
ic markers, linguistics, and anthropometrics. In particular, much attention has
been directed at investigating genotypic and phenotypic variation among past and
present New World populations.
Historically, the Americas have been viewed as relatively homogenous,
with significant biological variability not occurring until initial European contact
and the subsequent influx of European and African populations, a view profound-
ly influenced by Morton and Hrdlicˇka (Powell and Neves 1999). This view of
minimal population variation in the Americas and therefore lack of great antiqui-
ty can be found at the core of Americanist studies until recently. Population ori-
gins traced to early demic expansion represent one preferred explanation for Na-
tive American homogeneity (Hrdlicˇka 1920; Turner 1985, 1994).
Linguistic evidence is another area of exploration used in the study of ear-
ly American migration models. Greenberg (1987) and others (Greenberg and
Ruhlen 1992; Greenberg et al. 1986) suggest that all living Amerindians are direct
descendants of a single founding population (with the assumption that a common
1C.A. Pound Human Identification Laboratory, University of Florida, Gainesville, FL 32611.
2Department of Anthropology, National Museum of Natural History, Smithsonian Institution, Washington,
D.C. 20560.
Human Biology, December 2002, v. 74, no. 6, pp. 807–818.
Copyright © 2003 Wayne State University Press, Detroit, Michigan 48201-1309
KEY WORDS: NEW WORLD, CRANIOMETRICS, MULTIVARIATE STATISTICS, HUMAN VARIA-
TION

808 / ross et al.
language indicates a common origin), which acts as a barrier to gene flow and in-
fluences the formation of population structures, operating much like geographic
isolation (Barbujani and Sokal 1990; Sokal et al. 1993). Alternatively, multiple
migration models have been presented by linguistic, genetic, dental, and cranio-
metric studies of late Pleistocene and early Holocene Paleo-Indians (Haydenblit
1996; Lahr 1995; Powell and Neves 1999; Neves and Pucciarelli 1991; Steele and
Powell 1993, 1994). Each of the models mentioned above requires that certain as-
sumptions be made about the amount of phenotypic variation present in the
Americas prior to European contact.
However, a comprehensive and systematic examination of precontact and
early-contact Latin American and Caribbean human skeletal remains for the study
of microevolutionary processes is still lacking. Most researchers have focused on
localized and regionalized studies, specifically South American and South An-
dean variation (Cocilovo and Rothhammer 1990, 1996, 1999; Rothhammer et al.
1982, 1984, 1985; Varela and Cocilovo 1999, 2000). Rather most researchers
have used a single typological group such as W.W. Howells’ Peruvian sample as
the morphological representative for all of South America (e.g., Steele and Pow-
ell 1994). The purpose of this paper is to present a preliminary study of the cra-
niometric variation in Latin America and the Caribbean using a broad spatial dis-
tribution of American groups. If precontact populations in the Americas were
relatively heterogeneous, this would be consistent with new findings suggesting
high variability among early American fossil crania and would further support
new evidence for a multiple population model for peopling of the New World
(Jantz and Owsley 2001).
Materials and Methods
Materials. Ten groups totaling 388 individuals are used in this study. Group
names, sample sizes, and provenience are listed in Table 1. The Terry black sam-
ple is included for comparison and to provide a comparable sample to represent
the imported African population. Only undeformed crania were selected and
males and females were pooled. Seven standard craniometric variables were uti-
lized in the analyses and were selected according to measurement availability
across samples (Table 2).
Statistics. In order to examine craniofacial variation in the Americas while di-
rectly accounting for size effects, size and shape variables were computed ac-
cording to Mosimann and colleagues (Mosimann and James 1979; Darroch and
Mosimann 1985) using the raw measurements. Size is defined as the geometric
mean (GM) of all seven cranial variables. The GM of n variables is calculated as
GMY = n


n
i=1
Yi, (1)