Stable isotopes from the African site of Elmina, Ghana and their usefulness in tracking the provenance of enslaved individuals in 18th‐ and 19th‐century North American populations

Abstract

Objectives:
Stable isotope values for historic period human remains from Elmina, Ghana, are compared to isotope data from 18th- and 19th-century North American sites as a test case for examining African origins and identifying first generation Africans in the Mid-Atlantic region of the United States.

Materials and methods:
Stable carbon, nitrogen, and oxygen isotope values were measured in skeletal remains. Values from the cosmopolitan port city of Elmina provide the first available reference data from Africa during this time period and region. These values serve as a proxy for West African groups in general which are statistically compared to Euro-Americans and African Americans.

Results:
Elmina carbon isotope values are relatively higher than those of North Americans, and African Americans show greater statistical similarity to West Africans. Elmina nitrogen isotope values are higher than those of North Americans. Elmina oxygen isotope values are notably higher than those in all Mid-Atlantic North American sites in this study.

Discussion:
Similarity in carbon isotope values between Elmina and African Americans suggests commonalities in food availability or food preferences between these groups. Elevated nitrogen isotope values in Elmina individuals support the documented reliance of the local population on marine dietary resources at this coastal port. While carbon and nitrogen isotopes provide insight into foodways, oxygen isotope data, sourced from drinking water, provide better geographical information. The higher oxygen values from Elmina not only differentiate this group from North American Mid-Atlantic sites, but also make it possible to identify outliers at these sites as potential recent arrivals from West Africa.

Full text

RESEARCH ARTICLE
Stable isotopes from the African site of Elmina, Ghana and
their usefulness in tracking the provenance of enslaved
individuals in 18th- and 19th-century North American
populations
Christine A. M. France
1
| Douglas W. Owsley
2
| Karin S. Bruwelheide
2
|
Emily S. Renschler
3
| Kathryn G. Barca
2
| Christopher R. DeCorse
4
1
Smithsonian Museum Conservation Institute,
Suitland, Maryland
2
Department of Anthropology, Smithsonian
National Museum of Natural History,
Washington, District of Columbia
3
University of Pennsylvania Museum of
Archaeology and Anthropology, Philadelphia,
Pennsylvania
4
Department of Anthropology, Syracuse
University, Syracuse, New York
Correspondence
Christine A. M. France, Smithsonian Museum
Conservation Institute, 4210 Silver Hill Road,
Suitland, MD 20746.
Email: francec@si.edu
Funding information
National Science Foundation, Grant/Award
Number: SMA-1156360; Rice Endowment for
Forensic Anthropology
Abstract
Objectives: Stable isotope values for historic period human remains from Elmina,
Ghana, are compared to isotope data from 18th- and 19th-century North American
sites as a test case for examining African origins and identifying first generation
Africans in the Mid-Atlantic region of the United States.
Materials and methods: Stable carbon, nitrogen, and oxygen isotope values were
measured in skeletal remains. Values from the cosmopolitan port city of Elmina pro-
vide the first available reference data from Africa during this time period and region.
These values serve as a proxy for West African groups in general which are statisti-
cally compared to Euro-Americans and African Americans.
Results: Elmina carbon isotope values are relatively higher than those of North Amer-
icans, and African Americans show greater statistical similarity to West Africans.
Elmina nitrogen isotope values are higher than those of North Americans. Elmina
oxygen isotope values are notably higher than those in all Mid-Atlantic North Ameri-
can sites in this study.
Discussion: Similarity in carbon isotope values between Elmina and African Ameri-
cans suggests commonalities in food availability or food preferences between these
groups. Elevated nitrogen isotope values in Elmina individuals support the docu-
mented reliance of the local population on marine dietary resources at this coastal
port. While carbon and nitrogen isotopes provide insight into foodways, oxygen iso-
tope data, sourced from drinking water, provide better geographical information. The
higher oxygen values from Elmina not only differentiate this group from North Amer-
ican Mid-Atlantic sites, but also make it possible to identify outliers at these sites as
potential recent arrivals from West Africa.
KEYWORDS
Africa, Atlantic slave trade, North America, stable isotopes
Received: 21 November 2018 Revised: 23 May 2019 Accepted: 3 October 2019
DOI: 10.1002/ajpa.23946
Published 2019. This article is a U.S. Government work and is in the public domain in the USA.
Am J Phys Anthropol. 2019;1–21. wileyonlinelibrary.com/journal/ajpa 1

1|INTRODUCTION
While historians and archaeologists have known about the broad pat-
terns of the Atlantic slave trade, including those areas in Africa from
which trading countries exported enslaved individuals, specific origins
for skeletal remains recovered from archaeological sites in the United
States can rarely be determined. A particular African cultural group is
sometimes suggested by housing, foods, religious and personal arti-
facts, preserved historic documents, mortuary practices, and other
cultural indicators if such information is available (Blakey, 1998; DeC-
orse, 1999; Fennell, 2011; Ogundiran & Falola, 2007; Singleton, 1995,
1999). Traditionally, features of the skull and dentition have been
used to assess the ancestral origins of skeletal remains (Blakey and
Rankin-Hill, 2009; Gill & Rhine, 1990; Jantz & Ousley, 2005; Spradley,
2006), but these methods do not distinguish first generation Africans
from those born in North America of African parents. Even DNA is
inadequate in this respect since subsequent generations of Africans
born in North America may not have genetic admixture with non-
African groups. Intentional dental modification has arguably been the
only other means used to determine recent arrival to the Americas on
the basis of skeletal remains. This practice has been noted in studies
from North and Central America, and the Caribbean (Blakey, 1998;
Blakey & Rankin-Hill, 2009; Handler, Corruccini, & Mutaw, 1982;
Handler, 1994; Ortner, 1966; Price et al., 2012; Schroeder, Haviser, &
Price, 2014; Stewart & Groome, 1968; Tiesler, 2002). However, the
historic occurrence of distinctive dental modification patterns over-
laps across African regions, varies through time, and has not been
studied adequately to allow a definitive determination of regional ori-
gin. Furthermore, the practice has not been proven to be exclusive to
first-generation Africans in the Americas (Rivero de la Calle, 1973;
Roksandic, Alarie, Suárez, Huebner, & Roksandic, 2016).
This study examines stable carbon, nitrogen, and oxygen isotope
values from the cosmopolitan coastal site of Elmina, Ghana in West
Africa and compares these data to values from historic sites in North
America. To date, isotope studies of historic period remains in North
America have focused on origins and demographic factors within the
Americas because no comparable African data existed from this time
period. Stable isotope values from Elmina allow comparisons to be
made and appear unique in some respects from isotope values of indi-
viduals from the Mid-Atlantic region of the United States. In essence,
Elmina values can serve as a proxy for recent West African arrivals to
the Mid-Atlantic, quantitatively distinguishing them from African
Americans born in this region.
Stable isotopes help determine resource use by, and thus regional
origins of, historic period North American populations, including
enslaved individuals (Bruwelheide et al., 2019; France, Owsley, &
Hayek, 2014; Raynor & Kennett, 2008; Ubelaker & Owsley, 2003).
Carbon isotope ratios reflect regional vegetation availability to both
humans and animals, and can separate region of origin only so far as
certain regions tend to rely on different grain sources. Carbon is incor-
porated into the hydroxyapatite carbonate (δ
13
C
carbonate
), as well as
the collagen protein within bone and tooth dentin (δ
13
C
collagen
). Values
are reported in standard delta notation where δ
13
C=
[(
13
C/
12
C
sample
−
13
C/
12
C
standard
)/
13
C/
12
C
standard
]×1,000; units are in
permil (‰), and the standard is Vienna Pee Dee Belemite. Carbon iso-
topes fractionate differently depending on whether a plant employs
the C3 or C4 photosynthetic pathway. C3 plants (wheat, barley, rice,
trees, shrubs, and temperate/cool climate grasses) show more nega-
tive δ
13
C values (approximately −33‰to −24‰), and C4 plants
(maize, millet, sorghum, sedges, sugarcane, and warm/dry climate
grasses) show relatively higher values (approximately −16‰to
−10‰) (Heaton, 1999; O'Leary, 1988; Smith & Epstein, 1971). Car-
bon in hydroxyapatite carbonates primarily reflects the carbohydrate
and lipid carbon isotope dietary input, while collagen carbon primarily
reflects the protein dietary input (Ambrose & Norr, 1993; Fernandes,
Nadeau, & Grootes, 2012; Jim, Ambrose, & Evershed, 2004; Krueger &
Sullivan, 1984). Although carbon isotopes fractionate during incorpo-
ration into tissues, the C3/C4 pattern is still observable (Balasse,
Bocherens, & Mariotti, 1999; Hedges, 2003; Kohn & Cerling, 2002;
Passey et al., 2005; van der Merwe, 1982). Therefore δ
13
C
carbonate
values largely indicate the types of plants and grains consumed
directly by an individual, while δ
13
C
collagen
values are heavily
influenced by the plant and grain fodder for consumed animals.
Nitrogen isotopes, incorporated exclusively into collagen in bone
and dentin, reflect the amount of protein input or marine resources in
the diet. Values are reported in standard delta notation (δ
15
N
collagen
)
where the ratio of interest is
15
N/
14
N, and the standard is atmo-
spheric air. Both increased protein and/or marine resources result in
higher δ
15
N
collagen
values (Bocherens & Drucker, 2003; DeNiro &
Epstein, 1981; Fogel, Tuross, Johnson, & Miller, 1997; Schoeninger &
DeNiro, 1984) and tend to indicate localized availability of food within
a region or population. Nitrogen values are not necessarily correlated
with broad regional origins.
Oxygen isotope values have proven the most effective at deter-
mining region of origin within North America because there are signif-
icant differences between northern and southern areas. Oxygen
isotopes are incorporated into bone, tooth enamel, and tooth dentin
in carbonates within the mineral hydroxyapatite. Values are reported
in standard delta notation (δ
18
O
carbonate
) where the ratio of interest is
18
O/
16
O, and the standard is Vienna Standard Mean Ocean Water.
The primary pool of oxygen integrated into hydroxyapatite during
mineralization is body water, which directly reflects oxygen isotope
ratios in drinking water (Bryant & Froelich, 1995; D'Angela &
Longinelli, 1990; Daux et al., 2008; Kohn, 1996; Levinson, Luz, &
Kolodny, 1987; Longinelli, 1984; Luz & Kolodny, 1985; Luz,
Kolodny, & Horowitz, 1984). Prior to the 20th-century, drinking water
in North America and Africa was obtained largely from local meteoric
water with oxygen isotope values correlated to latitude and general
region of origin (Bowen & Wilkinson, 2002; Dutton, Wilkinson,
Welker, Bowen, & Lohmann, 2005; Kendall & Coplen, 2001;
Landwehr, Coplen, & Stewart, 2014). Oxygen isotopes will fractionate
during the incorporation into hydroxyapatite carbonates
(i.e., δ
18
O
carbonate
), but this fractionation is expected to be constant
across the human species. As such, observed differences between
oxygen isotopes in North America versus Africa will be maintained in
2FRANCE ET AL.

archaeological remains. Some overlap in δ
18
O meteoric water values
exists between North America and Africa, specifically between the
southern United States and northern Africa. The δ
18
O values of North
American meteoric water range from approximately −21 to −1‰.
Values in Africa range from approximately −11 to +4‰(Figure 1).
While this may be a complicating factor in interpreting data from
archaeologically recovered African American remains from southern
locales and the Caribbean, isotope values from the Mid-Atlantic
should be distinct.
2|MATERIALS
The single site of Elmina holds four centuries of burials representing
both free and enslaved Africans of diverse heritage. Effective compar-
ison with North American remains utilizes eleven different sites in
Mid-Atlantic States, and one in New Mexico (a battlefield burial for
Confederate soldiers from Texas; Table 1, Supporting information
Table S1).
2.1 |Elmina, Ghana
Elmina, in coastal Ghana, was already settled by Akan people before
the region was reached by Portuguese traders in the 15th-century
(Figure 1). It was one of the larger settlements on the coast, which
was one of the reasons the Portuguese selected it as the site of
Castelo de S ~
ao Jorge da Mina (Castle of St. Jorge of the Mine), so
named because of the importance of the gold trade on this part of the
African coast. Founded in 1482, the fortress of Elmina was the first
and largest of the European outposts established in sub-Saharan
Africa (DeCorse, 2010). The castle remained the principal Portuguese
trade entrepôt on the West Africa coast until its capture by the Dutch
in 1637, when Elmina became the Dutch headquarters (DeCorse,
2001; Feinberg, 1989). During the 17th-century, slaves replaced gold
as the primary export from the Ghanaian coast, although the Elmina
population itself was not the direct source for exported slaves.
Enslaved Africans destined for trans-Atlantic trade were brought to
the Castle from a variety of locations across Ghana, and other parts of
West and Central Africa (Postma, 2003; Van den Boogaart & Emmer,
FIGURE 1 (Top) Oxygen
isotope values of meteoric water
in North America and Africa
(Bowen, West, Miller, Zhao, &
Zhang, 2014). (Lower inset)
Primary regions in Africa from
which enslaved individuals were
exported (Voyages: The Trans-
Atlantic Slave Trade Database,
2017). As a point of reference,
the Windward Coast and Gold
Coast are roughly equivalent to
modern Liberia and Ghana,
respectively
FRANCE ET AL.3

1979). Once exported, most Dutch trading ships were bound for the
West Indies and Brazil (Postma, 1990).
While Elmina served as a primary export site for the Dutch slave
trade, the settlement supported a diverse population of free Afri-
cans, as well as enslaved Africans living in their households. The pop-
ulation of Elmina grew increasingly heterogeneous during the Dutch
period with immigrants arriving from adjacent areas of the coast and
hinterland (Baesjou, 1979; DeCorse, 2001; Feinberg, 1989; Yarak,
1990). Population figures for West Africa in general are limited until
the late 19th and 20th centuries (DeCorse, 2001, 2008). However,
at Elmina the population expanded from a village of a few hundred
people in the 15th-century to a settlement of fifteen to twenty thou-
sand inhabitants by 1870. Most of the town's inhabitants were
coastal Akan, but there were also traders and immigrants from other
parts of the coast including interior Akan from Asante, and Akim,
Denkira, and Ewe from the eastern portion of modern Ghana. Slaves
brought from the northern regions of modern Ghana may also have
lived within the town.
In 1986, 1990, and 1993 multiple burials from spatially distinct
loci within the Elmina settlement site were excavated. The excava-
tions and associated anthropological interpretations are extensively
documented in DeCorse (2001) and a preliminary discussion of the
skeletal material recovered is presented in Renschler and DeCorse
(2016); summarized information is presented here. The individuals
whose remains are considered are native Africans that lived during
the 17th, 18th, and 19th centuries, within the period when the Dutch
controlled Elmina Castle. The majority of the burials recovered were
likely free Africans of local ancestry. Most were recovered from
beneath house floors; burial within the house is a traditional Akan
burial practice. However, it is difficult to postulate the origins of the
individuals based on archaeological data alone because there is little
information on the organization of Elmina with regard to the associa-
tion of portions of the settlement with specific ethnic groups. It is
possible that immigrants settled within specific areas of the town.
There is some historic information that immigrants were buried in sep-
arate burial areas. As the majority of the burials were recovered from
beneath the floors of stone structures close to Elmina Castle, and
adjacent to the market, it is probable that they represent individuals
of relatively high socioeconomic status, although enslaved individuals
worked and lived in houses along with their owners. While separate
burial areas may have been located for both immigrants and slaves,
there is insufficient information to be certain of the relationship of the
persons buried at the individual loci. The burials from Locus G are the
exception, as this area located at the western margins of the Elmina
TABLE 1 Site information
Site
a,b
Site location
Time
period Ancestry Social status Total
c
Elmina Ghana 1600-1899 African Mostly free local residents, a few
enslaved
41 (49)
A.P. Hill Fort A.P. Hill,
VA
1780–1830 African
American
Enslaved, rural 4 (4)
Congressional Cemetery Washington, DC 1850–1899 Caucasian High status, urban 42 (69)
First African Baptist Church
(FABC)
Philadelphia, PA 1824–1842 African
American
Free, possibly former slave, urban 9 (138)
Foscue Plantation North Carolina 1800–1849 Caucasian High status, rural plantation 6 (9)
Glorieta Pass New Mexico d. 1862 Caucasian Confederate Civil War soldier 31 (31)
Hilleary Cemetery Maryland 1850–1899 Caucasian High status, rural plantation 10 (12)
Kincheloe Cemetery Virginia 1830–1860 Caucasian Middle–high status, rural 3 (4)
Parkway Gravel Delaware 1780-1830 African
American
Enslaved or former slave, rural 5 (5)
Pettus Virginia 1700–1799 African
American
Enslaved, rural 21 (26)
Robinson Cemetery Virginia 1775–1875 African
American
Enslaved, rural 5 (9)
Walton Family Cemetery Connecticut 1750–1830 Caucasian Farming family, rural 20 (28)
Woodville Cemetery Delaware 1790–1850 Caucasian Middle class, rural 10 (10)
a
Site references: A.P. Hill (McLearen, McCartney, Kiser, & Richards, 2003), Congressional Cemetery (Owsley et al., 2017; Owsley, Pearlstein, &
Bruwelheide, 2016; Pearlstein, Owsley, & Bruwelheide, 2014), First African Baptist Church (Crist, Roberts, Pitts, McCarthy, & Parrington, 1997), Foscue
Plantation (Seeman, 2011), Glorieta Pass (Owsley, 1994), Hilleary Cemetery (Child & Kosack, 2013), Kincheloe Cemetery (Imlay, 2011), Parkway Gravel
(Imlay, 2012; Mancl, 2007), Pettus (Fesler, 2011), Robinson Cemetery (McDonald & Meacham, 2001), Walton Family Cemetery (Bellantoni, Sledzik, &
Poirier, 1997), Woodville Cemetery (Doms et al., 1995). All materials curated at Smithsonian National Museum of Natural History with the exception of
Robinson Cemetery (Radford University) and Elmina (Syracuse University).
b
Individuals from Congressional Cemetery, Glorieta Pass, Hilleary Cemetery, Walton Cemetery, and First African Baptist Church have been reinterred.
c
Number of individuals sampled for this study (total individuals recovered from site).
4FRANCE ET AL.

settlement is known to have been occupied by enslaved individuals
owned by the Dutch West India Company.
Based on the settlement's history, burials at Elmina represent a
somewhat heterogeneous population drawn from geographic regions
similar to those of exported enslaved Africans brought to the Mid-
Atlantic region of North America. The approximate area represented
by these ethnic groups, roughly from coastal Ghana east to the Bight
of Benin and north to northern Ghana, Togo, and Côte d'Ivoire, is
between 4and 12north latitude and −5west and 10east longi-
tude. The archaeological remains at Elmina and the isotope profiles
therein provide a plausible proxy for native West Africans who were
enslaved and exported to the Americas. The British slave trade,
responsible for a majority of enslaved individuals imported into North
America, included individuals from regions at similar latitudes to
Elmina (Liberia to the Bight of Benin) and from regions further south
(Bight of Biafra to western Central Africa) (Anstay, 1975; Curtin,
1969; Lovejoy, 1989; Postma, 2003; Walsh, 2001). Similarly, enslaved
individuals transported on American ships hailed primarily from sites
at similar latitudes to Elmina (Senegambia, Sierra Leone, Liberia, and
Ghana). The isoscape in Africa (Figure 1) suggests then that enslaved
persons imported on British ships would most likely have similar, or
higher δ
18
O
carbonate
values than individuals at Elmina, while those
imported on American ships should have values similar to those at
Elmina. The oxygen isotope values from Elmina burials are essentially
the lowest isotope values expected in exported enslaved Africans that
has maximum potential overlap with isotope values in North
Americans.
2.2 |North American sites
Twelve 18th- and 19th- century archaeological sites spanning various
North American regions are included in this study: 11 sites from the
Mid-Atlantic region and 1 site from the Southwest. Some sites are
comprised of individuals with African ancestry from the late 1700s
and early decades of the 1800s during the height of the Atlantic slave
trade. Included are three Virginia sites (A.P. Hill, Pettus, and Robinson
Cemetery) and one Delaware site (Parkway Gravel). Three Euro-
American sites serve as comparative samples of individuals who were
born, with possible exceptions, in North America. They are from North
Carolina (Foscue Plantation), Connecticut (Walton Family Cemetery),
and Delaware (Woodville Cemetery).
Individuals from the mid-1800s to approximately 1900 included in
this study are free African Americans from the First African Baptist
Church (referred to as FABC), in Philadelphia, Pennsylvania. Although
no records exist detailing the geographic origin of these individuals,
it is likely they were American-born. Also from the late 1800s are
Euro-Americans from family vaults in Congressional Cemetery,
Washington, DC, and more rural cemeteries in Maryland (Hilleary
Cemetery) and Virginia (Kincheloe Plantation Cemetery). Members of
these extended families, of which some individuals have known iden-
tity with documented historical and genealogical information, were
born in North America, or in a few cases Europe, as this time period
saw a high volume of immigration into the United States. Also
included in this analysis are Civil War soldiers from Glorieta Pass,
New Mexico. These Confederate soldiers from Texas provide a com-
parative series from the southern United States. Table S1 lists the
individuals included in the analysis by archaeological site, time period,
and socio-economic status.
3|METHODS
Both bone and tooth samples were included in subsequent analyses.
Selection of material was based largely on sample availability. When
both bone and teeth were available from an individual, a tooth was
selected for this study. Approximately 24% of the remains had avail-
able teeth; the majority of teeth are from the Glorieta Pass site
(Table S1). Teeth do not remodel after mineralization and provide a
better assessment of childhood origins compared to bone which
remodels throughout life. The inclusion of bone from adult individuals
in the comparative North American population reduces the visibility
of recently arrived African individuals in the data set. However, the
goal of this study is to provide a comparative data set that reflects a
population of people that were most likely born in North America or
spent significant time there. If a set of mixed North American bone
and teeth show isotopic distinction from the Elmina individuals, it is
likely that recent arrivals from the latter (and other African localities)
will appear as outliers compared to the former.
Solid bone and tooth dentin samples for collagen isotope and ele-
mental analyses were obtained by coring with a rotary tool or extrac-
tion with pliers. Powdered bone, dentin, and enamel samples for
carbonate isotope and Fourier transform infrared (FTIR) spectroscopy
analyses were obtained by crushing with a mortar and pestle or dril-
ling with a rotary tool. Collagen and carbonates were extracted from
bone, dentin, and enamel according to methods detailed in France
et al. (2014). Briefly summarized, collagen in bone and dentin was
extracted via a standard acid–base–acid method including deminerali-
zation in cold hydrochloric acid, humic and fulvic acid removal with
sodium hydroxide, denaturing the collagen in weak hot hydrochloric
acid, and isolation of collagen via lyophilization. Carbonates were iso-
lated by removal of organic material with sodium hypochlorite
followed by buffered acetic acid to remove secondary diagenetic
carbonates.
All samples were analyzed on a Thermo Delta V Advantage mass
spectrometer (Thermo Fisher Scientific, Waltham, MA) in continuous
flow mode at the Smithsonian MCI Stable Isotope Mass Spectrometry
Laboratory. Collagen samples were weighed into tin cups and
combusted on a Costech 4010 Elemental Analyzer (Costech Analytical
Technologies Inc., Valencia, CA). The purified N
2
and CO
2
gases were
transferred to the mass spectrometer via a Conflo IV interface and
measured for δ
15
N
collagen
and δ
13
C
collagen
values. Raw values were
corrected to an acetanilide house reference material and Urea-UIN3
(Schimmelmann et al., 2009), both calibrated to USGS40 and USGS41
international reference materials. Weight % N and weight % C values
were calibrated using the acetanilide. Carbonate samples were
weighed into exetainer vials and flushed with pure helium. Samples
FRANCE ET AL.5

were acidified with concentrated phosphoric acid (SG > 1.92) for
24 hr at 25C. The released CO
2
was purified and transferred to the
mass spectrometer via a Thermo GasBench interface and measured
for δ
13
C
carbonate
and δ
18
O
carbonate
values. Raw values were corrected
to LSVEC and NBS-19 international reference materials. Errors for
δ
15
N
collagen
,δ
13
C
collagen
,δ
13
C
carbonate
, and δ
18
O
carbonate
are
±0.2‰(1σ).
Raw bone powders were analyzed using attenuated total reflec-
tance FTIR spectroscopy (ATR-FTIR) on a Thermo Nicolet 6700 FTIR
(Thermo Fisher Scientific, Waltham, MA) with Golden Gate ATR (dia-
mond crystal, single bounce, 45) equipped with a DTGS detector.
Spectra were collected for 128 scans from 450 to 4,000 cm
−1
with a
resolution of 4 cm
−1
. All baseline corrections and ratio calculations
were automated via TQAnalyst EZ version 8. Measured parameters
include phosphate peak (ѵ
4
) heights at 565 and 605 cm
−1
and the
associated valley at ~590 cm
−1
, phosphate peak (ѵ
1
) height at
~960 cm
−1
, phosphate peak (ѵ
3
) height at 1,035 cm
−1
, carbonate peak
(ѵ
3
) heights at 1,415 and 1,455 cm
−1
, and ѵ
1
PO
4
position. Using these
parameters, the following peak height ratios were calculated: infrared
splitting factor (IRSF) ([565 + 605]/590), carbonate/carbonate
(1,455/1,415), and carbonate/phosphate (1,415/1,035).
Potential postmortem diageneticalterationofcollagenisotope
values was examined using collagen yields obtained during extrac-
tion and elemental yields obtained during mass spectrometry ana-
lyses. Collagen extracted from well-preserved bones and teeth
should constitute ~2–20% whole bone/dentin weight, show a
weight % N of ~10–15%, and an atomic C:N ratio of 2.8–3.6
(Ambrose, 1990; DeNiro, 1985; Jorkov, Heinemeier, & Lynnerup,
2007; McNulty et al., 2002). Potential diagenetic alteration of bone
hydroxyapatite carbonate isotope values was examined using the
calculated peak height ratios from ATR-FTIR spectra. Based on pre-
vious ATR-FTIR studies and suggested conversions from the more
common transmission FTIR methods (Beasley, Bartelink, Taylor, &
Miller, 2014; Garvie-Lok, Varney, & Katzenberg, 2004; Lebon et al.,
2010, 2011; Snoeck, Lee-Thorp, & Schulting, 2014; Thompson,
Gauthier, & Islam, 2009; Thompson, Islam, Piduru, & Marcel, 2011;
Wright & Schwarcz, 1996), well-preserved hydroxyapatite should
have an IRSF of <4.4, carbonate/carbonate ratio (C/C) of ~0.9, car-
bonate/phosphate ratio (C/P) of ~0.3, and a ѵ
1
PO
4
position
<962.5 cm
−1
. Collagen and hydroxyapatite samples yielding these
values were considered well preserved and included in further ana-
lyses. A paucity of FTIR data in the literature precludes direct analy-
sis of tooth enamel as the different mineralization process of
enamel is expected to produce different peak height ratios than
those described above. However, enamel mineralization is generally
more dense than that of bone and dentin, and the former is often
considered more resistant to diagenesis than the latter. Therefore,
tooth enamel samples were considered well preserved if the
corresponding dentin met the collagen quality criteria outlined
above.
Isotope values were compared across all sites using nonparametric
Mann–Whitney tests due to small sample sizes and non-Gaussian dis-
tributions for some sites. For tooth samples, dentin data were used
for all δ
15
N
collagen
and δ
13
C
collagen
comparisons; enamel data were
used for all δ
18
O
carbonate
and δ
13
C
carbonate
comparisons unless only
dentin data were available for a particular tooth.
4|RESULTS
Isotope data for well-preserved samples are shown in Table 2. Only
samples meeting the preservation criteria outlined above are included
in further analyses and interpretations; all results from diagenesis test-
ing are included in Table S2. The δ
13
C
carbonate
values from Elmina
show an average of −5.9‰(±1.2, 1σ) with a range of −8.9 to −3.9‰
(Figure 2). The study's African Americans show a slightly more nega-
tive δ
13
C
carbonate
average of −7.1‰(±2.4, 1σ) with a greater range of
−11.5 to −2.8‰. Euro-Americans show a considerably more negative
δ
13
C
carbonate
average of −8.9‰(±2.1, 1σ) with the widest range of
−14.0 to −4.4‰. If the southwestern site of Glorieta Pass is removed,
the remaining Mid-Atlantic Euro-Americans show a lower δ
13
C
carbonate
average of −9.4‰(±1.7, 1σ) and a slightly smaller range of −13.3
to −6.0‰.
The δ
13
C
collagen
values show the same pattern as the δ
13
C
carbonate
values. Elmina has an average δ
13
C
collagen
value of −10.3‰(±1.6, 1σ)
and a range of −13.5 to −7.7‰(Figure 3). African Americans have a
slightly more negative δ
13
C
collagen
average of −12.0‰(±2.6, 1σ) with
a greater range of −17.0 to −8.2‰. A considerably more negative
average of −14.2‰(±2.0, 1σ) with a range of −19.7 to −9.2‰is
noted for Euro-Americans. Removing Glorieta Pass results in a Mid-
Atlantic Euro-American δ
13
C
collagen
average of −14.5‰(±1.7, 1σ) and
a slightly smaller range of −17.8 to −10.5‰.
There is less variation between regions in δ
15
N
collagen
values
(Figure 3). Elmina has an average δ
15
N
collagen
value of +11.9‰(±1.1,
1σ) with a range of +8.3 to +14.1‰. Euro-Americans and African
Americans show slightly lower averages of +10.7‰(±0.9, 1σ) and
+10.4‰(±0.7, 1σ), respectively. The range of δ
15
N
collagen
was only
slightly different among groups with Euro-Americans and African
American values extending from +8.1 to +13.2‰and +8.8 to
+11.9‰, respectively. Removing Glorieta Pass results in a similar
δ
15
N
collagen
average value for Mid-Atlantic Euro-Americans of
+10.7‰(±1.0, 1σ) with a range of +8.7 to +13.2‰.
The δ
18
O
carbonate
values from Elmina show an average of +27.6‰
(±1.0, 1σ) with a range of +23.3 to +28.9‰(Figure 2); most Elmina
δ
18
O
carbonate
values fall in the range of +26.1 to +28.9‰. Both Euro-
Americans and African Americans have lower δ
18
O
carbonate
averages
of +26.0‰(±2.6, 1σ) and +25.3‰(±1.2, 1σ), respectively. The African
Americans have a relatively smaller range of +22.0 to +27.7‰, while
the Euro-Americans show the greatest overall range of +15.9 to
+34.0‰. If Texans from Glorieta Pass are removed, remaining Mid-
Atlantic Euro-Americans show a lower δ
18
O
carbonate
average of
+24.5‰(±2.3, 1σ) with the same range of +15.9 to +34.0‰.
Site-to-site comparison of isotope averages using Mann–Whitney
tests are listed in Table 3. Sites are considered statistically different if
p<.05. The δ
13
C
collagen
and δ
13
C
carbonate
values from Elmina are consis-
tently distinct from Euro-Americans in the study with the exception
6FRANCE ET AL.

TABLE 2 Isotope data
Site ID Element
δ
15
N
collagen
(‰, air)
δ
13
C
collagen
(‰, V-PDB)
δ
13
C
carbonate
(‰, V-PDB)
δ
18
O
carbonate
(‰, V-SMOW)
Elmina ELMINA-A-L52 Femur 12.7 −9.9 −4.8 28.0
Elmina ELMINA-A-D51A Femur 10.7 −11.1 −5.5 25.2
Elmina ELMINA-A-E51B Molar-dentin 12.0 −12.7 −6.5 27.8
Elmina ELMINA-A-E51B Molar-enamel NA NA −5.5 27.9
Elmina ELMINA-A-E51F51 Femur 12.5 −12.3 −5.0 27.1
Elmina ELMINA-A-K45 Humerus 11.6 −11.0 −5.3 26.7
Elmina ELMINA-A-L44 Fibula 11.6 −12.9 −7.2 27.2
Elmina ELMINA-A-L45A Humerus 11.3 −13.5 −6.6 27.9
Elmina ELMINA-A-L49B Tibia 11.3 −11.1 −5.8 28.2
Elmina ELMINA-A-L49C Metatarsal 12.3 −11.2 −6.8 27.9
Elmina ELMINA-A-L49E Humerus 10.2 −13.1 −6.3 28.0
Elmina ELMINA-A-M47 Ulna 12.5 −8.8 −3.9 27.7
Elmina ELMINA-A-M52 Femur 8.3 −11.1 −4.8 28.4
Elmina ELMINA-A-O/51 Femur 14.1 −11.7 −6.9 28.1
Elmina ELMINA-A-Q/51 Femur 11.0 −11.4 −7.2 28.9
Elmina ELMINA-A-Y51A Temporal 12.3 −7.8 −6.2 27.3
Elmina ELMINA-A-Y51B Temporal 12.9 −11.8 −8.4 28.5
Elmina ELMINA-A-Y51C Femur 11.8 −7.8 −5.2 27.9
Elmina ELMINA-A-Y51D Femur 12.9 −8.2 −5.7 28.3
Elmina ELMINA-A-Y51E Femur 12.7 −8.0 −4.8 27.6
Elmina ELMINA-A-Y51G Femur 12.4 −9.1 −6.1 28.4
Elmina ELMINA-A-Y51H Tibia 12.4 −8.9 −5.3 28.1
Elmina ELMINA-A-Y51I Femur 12.9 −8.5 −5.1 27.7
Elmina ELMINA-A-Y51J Femur 11.2 −10.2 −6.0 28.2
Elmina ELMINA-A-Y51L Femur 13.2 −11.0 −8.9 27.7
Elmina ELMINA-A-Y51M Metatarsal 12.3 −11.1 −6.4 26.1
Elmina ELMINA-B-EE85A Humerus 12.6 −8.6 −4.3 28.1
Elmina ELMINA-B-EE85B Humerus 11.2 −10.5 −5.1 28.0
Elmina ELMINA-B-FF85A Tibia 10.2 −10.0 −4.2 28.0
Elmina ELMINA-B-FF85B Ulna 13.7 −7.7 −4.3 28.2
Elmina ELMINA-B-GG85A Clavicle 11.7 −8.9 −4.0 27.8
Elmina ELMINA-B-HH85B Humerus 12.3 −10.9 −6.1 28.2
Elmina ELMINA-B-HH85C Radius 11.7 −9.2 −5.4 28.1
Elmina ELMINA-E-E13 Clavicle 11.2 −10.8 −7.0 28.6
Elmina ELMINA-E-E13F13 Fibula 11.7 −10.2 −5.3 26.7
Elmina ELMINA-E-EF1618A Clavicle 12.6 −11.8 −6.0 26.8
Elmina ELMINA-E-EF1618B Femur 12.8 −10.6 −8.2 23.3
Elmina ELMINA-E-F16 Clavicle 12.4 −8.9 −4.7 28.0
Elmina ELMINA-G-GT3A Humerus 12.8 −9.4 −7.5 27.1
Elmina ELMINA-G-GT3C Femur 12.0 −10.4 −7.8 28.2
Elmina ELMINA-G-GT3D Humerus 10.0 −10.3 −5.2 27.0
Site average
†
11.9 −10.3 −5.9 27.6
Site SD(1σ)1.1 1.6 1.2 1.0
A.P. Hill 44CEAPHILL-VAOCME-1 Clavicle 10.3 −9.5 −5.5 22.2
A.P. Hill 44CEAPHILL-VAOCME-2 Femur 10.4 −9.2 −5.2 27.4
(Continues)
FRANCE ET AL.7

TABLE 2 (Continued)
Site ID Element
δ
15
N
collagen
(‰, air)
δ
13
C
collagen
(‰, V-PDB)
δ
13
C
carbonate
(‰, V-PDB)
δ
18
O
carbonate
(‰, V-SMOW)
A.P. Hill 44CEAPHILL-VAOCME-3 Ulna 11.2 −10.9 −6.2 26.1
A.P. Hill 44CEAPHILL-VAOCME-4 Femur 9.7 −13.8 −5.8 26.5
Site average 10.4 −10.9 −5.7 25.5
Site SD(1σ)0.6 2.1 0.4 2.3
Congressional
Cemetery
51CAUSTEN-CC-07 Metacarpal 10.3 −15.0 −9.4 24.3
Congressional
Cemetery
51CAUSTEN-CC-08 Metacarpal 11.3 −17.0 −11.7 21.7
Congressional
Cemetery
51CAUSTEN-CC-09 Rib 11.8 −15.6 −11.0 23.3
Congressional
Cemetery
51CAUSTEN-CC-13 Metacarpal 11.7 −16.1 −10.9 20.8
Congressional
Cemetery
51CAUSTEN-CC-14 Metacarpal 11.1 −17.2 −11.9 23.4
Congressional
Cemetery
51CAUSTEN-CC-16 Clavicle 10.8 −16.9 −12.2 21.4
Congressional
Cemetery
51KEYWORTH-CC-01 Metatarsal 11.8 −15.8 −10.8 24.4
Congressional
Cemetery
51KEYWORTH-CC-02 Metatarsal 10.7 −15.0 −9.0 24.3
Congressional
Cemetery
51KEYWORTH-CC-04 Radius 11.2 −15.0 −10.2 24.5
Congressional
Cemetery
51KEYWORTH-CC-05 Premolar-dentin 10.0 −16.2 −10.8 30.7
Congressional
Cemetery
51KEYWORTH-CC-05 Premolar-enamel NA NA −9.9 26.2
Congressional
Cemetery
51KEYWORTH-CC-06 Humerus 10.0 −16.5 −10.7 25.0
Congressional
Cemetery
51KEYWORTH-CC-07 Metatarsal 9.8 −17.3 −12.1 23.4
Congressional
Cemetery
51KEYWORTH-CC-08 Tibia 9.8 −17.4 −11.8 24.1
Congressional
Cemetery
51KEYWORTH-CC-10 Metatarsal 11.1 −15.8 −10.9 23.1
Congressional
Cemetery
51KEYWORTH-CC-11 Temporal 11.3 −16.4 −6.0 24.5
Congressional
Cemetery
51KEYWORTH-CC-12A Premolar-dentin 12.2 −17.8 −13.3 24.8
Congressional
Cemetery
51KEYWORTH-CC-12A Premolar-enamel NA NA −13.3 26.3
Congressional
Cemetery
51KEYWORTH-CC-13 Metatarsal 10.8 −15.8 −9.8 25.3
Congressional
Cemetery
51KEYWORTH-CC-14 Metacarpal 10.5 −17.0 −12.9 26.0
Congressional
Cemetery
51RICHARDS-CC-02 Parietal 12.0 −13.6 −8.4 24.9
Congressional
Cemetery
51RICHARDS-CC-05 Metatarsal 12.7 −13.1 −7.1 25.5
Congressional
Cemetery
51RICHARDS-CC-06 Metatarsal 11.6 −14.6 −8.6 24.7
(Continues)
8FRANCE ET AL.

TABLE 2 (Continued)
Site ID Element
δ
15
N
collagen
(‰, air)
δ
13
C
collagen
(‰, V-PDB)
δ
13
C
carbonate
(‰, V-PDB)
δ
18
O
carbonate
(‰, V-SMOW)
Congressional
Cemetery
51RICHARDS-CC-07 Metacarpal 12.0 −12.8 −7.9 28.4
Congressional
Cemetery
51WHITE-CC-01 Metacarpal 11.0 −14.9 −10.5 25.1
Congressional
Cemetery
51WHITE-CC-02 Fibula 10.2 −13.7 −9.2 24.4
Congressional
Cemetery
51WHITE-CC-03 Metatarsal 11.0 −15.6 −10.2 24.6
Congressional
Cemetery
51WHITE-CC-07 Radius 10.9 −17.1 −10.7 24.5
Congressional
Cemetery
51WHITE-CC-08 Fibula 11.7 −13.0 −9.4 24.8
Congressional
Cemetery
51WHITE-CC-09A Radius 10.1 −15.5 −9.5 24.4
Congressional
Cemetery
51WHITE-CC-09B Metacarpal 10.3 −12.7 −7.9 23.3
Congressional
Cemetery
51WHITE-CC-10 Clavicle 12.1 −16.0 −11.3 25.1
Congressional
Cemetery
51WHITE-CC-11 Fibula 10.5 −15.5 −10.7 20.4
Congressional
Cemetery
51WHITE-CC-12A Metatarsal 10.7 −14.1 −10.3 24.1
Congressional
Cemetery
51WHITE-CC-12B Radius 10.2 −16.0 −10.1 20.4
Congressional
Cemetery
51WHITE-CC-13 Radius 10.6 −17.0 −11.8 21.3
Site average
†
11.0 −15.6 −10.2 24.1
Site SD(1σ)0.8 1.4 1.6 1.8
FABC FABC-08-107A Metacarpal 10.7 −16.2 −10.6 24.8
FABC FABC-08-3300 Metatarsal 8.8 −17.0 −11.5 24.2
FABC FABC-08-63B Metatarsal 10.5 −16.6 −11.1 23.8
FABC FABC-08-8000 Metacarpal 10.7 −12.4 −7.8 23.5
Site average 10.2 −15.6 −10.2 24.1
Site SD(1σ)0.9 2.1 1.7 0.5
Foscue
Plantation
31FOSCUE-ECU-1 Molar-dentin 11.7 −12.2 −8.3 27.8
Foscue
Plantation
31FOSCUE-ECU-2 Molar-enamel NA NA −8.4 26.7
Foscue
Plantation
31FOSCUE-ECU-3 Ulna 10.5 −13.1 −9.0 25.8
Foscue
Plantation
31FOSCUE-ECU-4 Femur 11.3 −14.3 −8.5 24.0
Foscue
Plantation
31FOSCUE-ECU-5 Premolar-dentin 11.8 −12.3 −8.3 26.7
Foscue
Plantation
31FOSCUE-ECU-5 Premolar-enamel NA NA −6.7 27.7
Site average
†
11.3 −13.0 −8.2 26.4
Site SD(1σ)0.6 1.0 0.9 1.6
Glorieta Pass GLO-099-1A Femur 11.5 −13.5 −7.5 27.0
(Continues)
FRANCE ET AL.9

TABLE 2 (Continued)
Site ID Element
δ
15
N
collagen
(‰, air)
δ
13
C
collagen
(‰, V-PDB)
δ
13
C
carbonate
(‰, V-PDB)
δ
18
O
carbonate
(‰, V-SMOW)
Glorieta Pass GLO-099-2A Molar-dentin 10.8 −15.5 −9.2 27.4
Glorieta Pass GLO-099-2A Molar-enamel NA NA −9.5 26.4
Glorieta Pass GLO-099-2AA Canine-dentin 10.2 −12.2 −6.8 28.4
Glorieta Pass GLO-099-2AA Canine-enamel NA NA −6.0 28.3
Glorieta Pass GLO-099-2B Canine-dentin 10.1 −11.9 −6.8 28.7
Glorieta Pass GLO-099-2B Canine-enamel NA NA −7.4 27.2
Glorieta Pass GLO-099-2BB Molar-dentin 12.1 −13.7 −8.1 28.3
Glorieta Pass GLO-099-2BB Molar-enamel NA NA −7.4 28.9
Glorieta Pass GLO-099-2C Molar-dentin 10.0 −12.3 −7.9 30.5
Glorieta Pass GLO-099-2C Molar-enamel NA NA −8.1 27.4
Glorieta Pass GLO-099-2CC Molar-dentin 8.1 −18.2 −12.9 26.3
Glorieta Pass GLO-099-2CC Molar-enamel NA NA −13.0 25.7
Glorieta Pass GLO-099-2D Canine-dentin 10.3 −12.7 −6.4 30.8
Glorieta Pass GLO-099-2DD Canine-enamel NA NA −6.7 27.4
Glorieta Pass GLO-099-2E Femur 10.4 −12.9 −7.0 26.5
Glorieta Pass GLO-099-2EE Canine-dentin 11.0 −10.3 −5.9 29.2
Glorieta Pass GLO-099-2EE Canine-enamel NA NA −4.4 29.5
Glorieta Pass GLO-099-2G Canine-dentin 10.9 −19.7 −13.1 26.6
Glorieta Pass GLO-099-2G Canine-enamel NA NA −14.0 27.6
Glorieta Pass GLO-099-2H Molar-dentin 11.0 −12.6 −6.7 28.7
Glorieta Pass GLO-099-2H Molar-enamel NA NA −6.8 28.4
Glorieta Pass GLO-099-2I Canine-dentin 10.0 −12.2 −7.4 28.4
Glorieta Pass GLO-099-2I Canine-enamel NA NA −7.4 28.4
Glorieta Pass GLO-099-2J Canine-dentin 10.9 −12.5 −7.4 28.8
Glorieta Pass GLO-099-2J Canine-enamel NA NA −8.5 28.3
Glorieta Pass GLO-099-2K Molar-dentin 10.8 −11.6 −6.2 29.1
Glorieta Pass GLO-099-2K Molar-enamel NA NA −6.4 28.8
Glorieta Pass GLO-099-2L Canine-dentin 11.8 −15.8 −11.8 26.8
Glorieta Pass GLO-099-2L Canine-enamel NA NA −12.3 26.4
Glorieta Pass GLO-099-2M Molar-dentin 9.9 −12.1 −5.7 28.9
Glorieta Pass GLO-099-2M Molar-enamel NA NA −5.7 28.1
Glorieta Pass GLO-099-2N Molar-dentin 11.7 −13.5 −8.1 28.1
Glorieta Pass GLO-099-2N Molar-enamel NA NA −9.1 27.6
Glorieta Pass GLO-099-2O Molar-dentin 11.9 −11.6 −6.6 29.2
Glorieta Pass GLO-099-2O Molar-enamel NA NA −5.7 27.8
Glorieta Pass GLO-099-2P Canine-dentin 10.1 −9.2 −7.2 28.9
Glorieta Pass GLO-099-2P Canine-enamel NA NA −7.4 28.1
Glorieta Pass GLO-099-2Q Molar-dentin 11.5 −13.3 −8.8 28.5
Glorieta Pass GLO-099-2Q Molar-enamel NA NA −8.6 26.8
Glorieta Pass GLO-099-2R Molar-dentin 10.6 −10.9 −6.1 28.1
Glorieta Pass GLO-099-2R Molar-enamel NA NA −5.7 26.8
Glorieta Pass GLO-099-2S Molar-dentin 10.9 −14.0 −9.5 28.6
Glorieta Pass GLO-099-2S Molar-enamel NA NA −9.6 30.1
Glorieta Pass GLO-099-2T Canine-dentin 10.3 −15.0 −7.5 29.6
Glorieta Pass GLO-099-2T Canine-enamel NA NA −6.7 29.6
(Continues)
10 FRANCE ET AL.

TABLE 2 (Continued)
Site ID Element
δ
15
N
collagen
(‰, air)
δ
13
C
collagen
(‰, V-PDB)
δ
13
C
carbonate
(‰, V-PDB)
δ
18
O
carbonate
(‰, V-SMOW)
Glorieta Pass GLO-099-2U Canine-dentin 9.2 −18.8 −12.0 26.8
Glorieta Pass GLO-099-2U Canine-enamel NA NA −12.4 26.3
Glorieta Pass GLO-099-2V Molar-dentin 10.7 −12.7 −6.7 30.1
Glorieta Pass GLO-099-2V Molar-enamel NA NA −5.8 28.8
Glorieta Pass GLO-099-2X Incisor-dentin 10.4 −13.9 −7.8 28.1
Glorieta Pass GLO-099-2X Incisor-enamel NA NA −7.6 29.1
Glorieta Pass GLO-099-2Y Molar-dentin 11.7 −10.7 −10.7 26.5
Glorieta Pass GLO-099-2Y Molar-enamel NA NA −13.2 25.3
Glorieta Pass GLO-099-2Z Canine-dentin 9.6 −12.1 −6.3 28.5
Glorieta Pass GLO-099-2Z Canine-enamel NA NA −6.5 28.9
Site average
†
10.6 −13.3 −8.1 27.9
Site SD(1σ)0.9 2.4 2.5 1.3
Hilleary
Cemetery
18PR978-HILLEARY-FEA10 Molar-dentin 10.9 −13.4 −8.8 25.4
Hilleary
Cemetery
18PR978-HILLEARY-FEA10 Molar-enamel NA NA −7.5 25.7
Hilleary
Cemetery
18PR978-HILLEARY-FEA2 Clavicle 10.4 −14.7 −9.8 23.6
Hilleary
Cemetery
18PR978-HILLEARY-FEA3 Metatarsal 9.7 −14.2 −9.9 23.2
Hilleary
Cemetery
18PR978-HILLEARY-FEA4 Metacarpal 11.2 −13.2 −8.7 21.9
Hilleary
Cemetery
18PR978-HILLEARY-FEA5 Temporal 10.6 −14.2 −10.1 15.9
Hilleary
Cemetery
18PR978-HILLEARY-FEA7 Molar-enamel NA NA −6.9 24.9
Hilleary
Cemetery
18PR978-HILLEARY-FEA8 Molar-enamel NA NA −6.9 34.0
Hilleary
Cemetery
18PR978-HILLEARY-G Metacarpal 11.0 −13.9 −9.4 21.4
Hilleary
Cemetery
18PR978-HILLEARY-H Clavicle 9.8 −14.1 −9.7 23.7
Hilleary
Cemetery
18PR978-HILLEARY-R Metacarpal 9.0 −15.8 −11.0 23.7
Site average
†
10.3 −14.2 −9.0 23.8
Site SD(1σ)0.8 0.8 1.4 4.5
Kincheloe
Cemetery
44PWKINCHELOE-SI9114-A Humerus 12.9 −10.5 −6.1 23.0
Kincheloe
Cemetery
44PWKINCHELOE-SI9114-C Temporal 13.2 −12.1 −8.7 25.3
Site average 13.1 −11.3 −7.4 24.2
Site SD(1σ)0.2 1.1 1.9 1.6
Parkway Gravel 7NCE176-DHCA-V01 Temporal 10.0 −14.3 −9.9 24.9
Parkway Gravel 7NCE176-DHCA-V02 Temporal 10.6 −11.5 −7.1 24.9
Parkway Gravel 7NCE176-DHCA-V03 Mandible 9.7 −11.5 −6.2 24.8
Parkway Gravel 7NCE176-DHCA-V04 Mandible 10.8 −15.3 −9.4 23.8
Parkway Gravel 7NCE176-DHCA-X01L Molar-dentin 10.6 −12.8 −7.7 24.5
(Continues)
FRANCE ET AL.11

TABLE 2 (Continued)
Site ID Element
δ
15
N
collagen
(‰, air)
δ
13
C
collagen
(‰, V-PDB)
δ
13
C
carbonate
(‰, V-PDB)
δ
18
O
carbonate
(‰, V-SMOW)
Parkway Gravel 7NCE176-DHCA-X01L Molar-enamel NA NA −3.6 25.1
Site average
†
10.3 −13.1 −7.2 24.7
Site SD(1σ)0.4 1.7 2.6 0.5
Pettus 44JC33-PETTUS-191 Temporal 10.4 −12.5 −7.3 27.4
Pettus 44JC33-PETTUS-201 Temporal 9.1 −8.8 −9.9 25.4
Pettus 44JC33-PETTUS-205 Temporal 9.8 −9.9 −7.5 25.5
Pettus 44JC33-PETTUS-223 Temporal 10.1 −10.6 −6.0 25.4
Pettus 44JC33-PETTUS-231 Temporal 10.8 −15.2 −9.1 26.5
Pettus 44JC33-PETTUS-253 Temporal 10.0 −8.2 −7.5 27.7
Pettus 44JC33-PETTUS-270 Ulna 9.7 −9.9 −8.1 26.1
Pettus 44JC33-PETTUS-346 Metatarsal 9.4 −10.5 −5.0 25.4
Site average 9.9 −10.7 −7.5 26.2
Site SD(1σ)0.5 2.2 1.6 0.9
Robinson
Cemetery
44HE950-RADFORD-10 Metatarsal 11.3 −14.9 −8.4 25.6
Robinson
Cemetery
44HE950-RADFORD-15 Incisor-dentin 11.1 −10.0 −6.1 25.1
Robinson
Cemetery
44HE950-RADFORD-15 Incisor-enamel NA NA −2.8 25.6
Robinson
Cemetery
44HE950-RADFORD-16 Radius 10.8 −10.4 −5.9 24.9
Robinson
Cemetery
44HE950-RADFORD-18 Molar-dentin 10.7 −9.0 −5.3 25.3
Robinson
Cemetery
44HE950-RADFORD-18 Molar-enamel NA NA −3.2 25.5
Robinson
Cemetery
44HE950-RADFORD-5 Molar-dentin 11.9 −10.4 −7.6 22.1
Robinson
Cemetery
44HE950-RADFORD-5 Molar-enamel NA NA −4.0 25.5
Site average
†
11.2 −10.9 −4.9 25.4
Site SD(1σ)0.5 2.3 2.3 0.3
Walton Family
Cemetery
6CT58-5-AMM01 Femur 9.8 −13.8 −8.9 23.9
Walton Family
Cemetery
6CT58-5-AMM02 Femur 10.1 −13.6 −9.2 23.4
Walton Family
Cemetery
6CT58-5-AMM04A Femur 10.3 −15.1 −9.9 24.9
Walton Family
Cemetery
6CT58-5-AMM05 Femur 9.8 −15.9 −10.0 24.7
Walton Family
Cemetery
6CT58-5-AMM07 Femur 9.6 −15.0 −9.3 25.3
Walton Family
Cemetery
6CT58-5-AMM08A Femur 9.4 −13.8 −8.0 25.3
Walton Family
Cemetery
6CT58-5-AMM09 Humerus 9.7 −13.9 −8.2 23.9
Walton Family
Cemetery
6CT58-5-AMM11 Femur 9.5 −13.8 −8.8 23.0
Walton Family
Cemetery
6CT58-5-AMM19 Femur 9.7 −15.2 −9.7 25.6
(Continues)
12 FRANCE ET AL.

of the Kincheloe Cemetery. The Elmina δ
13
C
collagen
values are similar
to three of the five African American sites (i.e., Robinson Cemetery,
A.P. Hill, and Pettus). The Elmina δ
13
C
carbonate
values are also similar
to three of the five African American sites (i.e., Robinson Cemetery,
A.P. Hill, and Parkway Gravel). The Elmina δ
15
N
collagen
values are sta-
tistically distinct from all North American sites except the Foscue
Plantation.
The δ
18
O
carbonate
values from Elmina are distinct from every North
American site in the Mid-Atlantic. The δ
18
O
carbonate
values from
Texans buried at Glorieta Pass in New Mexico are not statistically dif-
ferent from Elmina, showing there are similarities between certain
areas of Africa and southern North America. However, the Glorieta
Pass values are also notably distinct from all Mid-Atlantic sites with
the exception of Foscue Plantation (although Glorieta and Foscue are
statistically distinct at p< .08). In the few North American sites where
bone and tooth were analyzed concurrently, the teeth tend to be
equal to the bone δ
18
O
carbonate
values, or slightly higher. However, the
differences could not be robustly tested given that all sites with both
elements consisted of a majority of either bone or tooth, with ≤3 sam-
ples of the alternate type.
5|DISCUSSION
Current knowledge of North American slave origins is limited to a
broad understanding of the Atlantic slave trade with exceptions
where historical records and archaeological evidence exist. Once
enslaved persons arrived in North America, they may have been
moved to several different locations, primarily within the mid- or
southern colonies or states, making it difficult to track origins. Despite
the 1807 Act Prohibiting the Importation of Slaves (effective in 1808),
populations of enslaved African Americans increased as children born
in North America were incorporated into the existing system of
TABLE 2 (Continued)
Site ID Element
δ
15
N
collagen
(‰, air)
δ
13
C
collagen
(‰, V-PDB)
δ
13
C
carbonate
(‰, V-PDB)
δ
18
O
carbonate
(‰, V-SMOW)
Walton Family
Cemetery
6CT58-5-AMM20 Humerus 9.6 −13.5 −8.6 24.2
Walton Family
Cemetery
6CT58-5-AMM21 Femur 9.9 −14.3 −9.5 25.0
Walton Family
Cemetery
6CT58-5-AMM22 Femur 10.0 −13.7 −9.5 22.5
Walton Family
Cemetery
6CT58-5-AMM23 Femur 8.7 −13.2 −7.3 24.7
Walton Family
Cemetery
6CT58-5-AMM25 Temporal 9.4 −13.7 −8.7 25.9
Walton Family
Cemetery
6CT58-5-AMM26 Rib 9.4 −13.8 −9.1 25.6
Walton Family
Cemetery
6CT58-5-AMM27 Temporal 9.6 −13.8 −9.0 24.5
Site average 9.7 −14.1 −9.0 24.5
Site SD(1σ)0.4 0.8 0.7 1.0
Woodville
Cemetery
7NCE98A- WOODVILLE-04 Fibula 11.4 −11.6 −6.9 26.0
Woodville
Cemetery
7NCE98A-
WOODVILLE-SLOPEB
Ulna 10.4 −12.1 −7.8 24.2
Woodville
Cemetery
7NCE98A-DHCA-01 Metacarpal 11.2 −11.3 −6.1 25.6
Woodville
Cemetery
7NCE98A-DHCA-03 Metatarsal 10.3 −13.6 −7.9 25.0
Woodville
Cemetery
7NCE98A-DHCA-08 Metatarsal 10.9 −10.9 −6.6 24.3
Woodville
Cemetery
7NCE98A-DHCA-12 Phalanges 12.0 −14.3 −8.1 25.2
Site average 11.0 −12.3 −7.2 25.1
Site SD(1σ)0.6 1.4 0.8 0.7
†
Dentin data are excluded from averages and standard deviations for δ
13
C
carbonate
and δ
18
O
carbonate
. See text for details.
FRANCE ET AL.13

enslavement. New generations of enslaved individuals are difficult
to distinguish from their first generation parents. Previous studies
have used oxygen, strontium, carbon, and nitrogen isotopes from
individuals in Central America, Brazil, Barbados, and the Dutch
Caribbean to confirm recent arrival of enslaved persons from Africa
and infer dietary resources (Bastos et al., 2016; Laffoon, Espersen, &
Mickleburgh, 2018; Laffoon, Valcárcel Rojas, & Hofman, 2013; Price
et al., 2012; Schroeder et al., 2014; Schroeder, O'Connell, Evans,
Shuler, & Hedges, 2009). These studies focused on origins and
demographic factors within the Americas and were unable to com-
pare enslaved individuals directly to African sites due to the lack of
comparable isotope data on historic human remains from West
Africa. Stable carbon, nitrogen, and oxygen isotope values from
Elmina, Ghana in this study are a promising step toward identifying
Africans newly arrived to the Mid-Atlantic.
Carbon and nitrogen isotopes in the Elmina population would
have been influenced by local food sources. A wide variety of
domesticated animals and crops were utilized at Elmina, including
millet, sorghum, multiple species of yams and, by the 17th-century, a
variety of American cultigens (DeCorse, 2001). Maize, a C4 dietary
staple in the Mid-Atlantic, was not native to Elmina or Africa, but
was brought there from the Americas. By the 17th-century,
cornbread and kenkey, a staple dish made from fermented ground
corn, were common. Fishing was a major part of the local economy
and marine foods were a significant dietary component at Elmina
(DeCorse, 2001).
The Elmina isotope results show higher δ
13
C
carbonate
and
δ
13
C
collagen
values than Mid-Atlantic Euro-Americans. They show
some overlap with the values of southern Euro-Americans and African
Americans (Figures 2 and 3). This is likely due to the greater
δ
δδ
FIGURE 2 Carbonate oxygen and
carbon isotope values compared between
Elmina and Euro-Americans (top), and
Elmina and African Americans (bottom).
Closed symbols represent bone values;
open symbols represent tooth values
14 FRANCE ET AL.

prevalence of C4 vegetation in southern North American regions and
heavy reliance on maize, especially in the diets of enslaved individuals.
The prevalence of C4 grains in African American diets is well docu-
mented in the historic and archaeological record (Bowes, 2011;
Bowes & Trigg, 2012; France et al., 2014; Franklin, 2001; Mrozowski,
Franklin, & Hunt, 2008). Bruwelheide et al. (2019) observed the pre-
dominance of C4-based diets in African Americans from Mid-Atlantic
sites in Virginia and eastern Maryland. Despite the observed overlap,
Elmina results trend toward higher values supporting the historical
evidence of significant C4 grains in the coastal Ghanaian diet by the
early 17th-century, particularly maize, millet, and sorghum. The
observed similarity between Elmina individuals and African Americans
suggests the latter group may have had diets limited to certain
resources, perhaps due to food availability or economic resources.
Additionally, the values may reflect retained cultural preferences for
certain foods and cooking styles.
Nitrogen isotope values from Elmina are somewhat distinct from
North American sites, but this isotope system does not serve as a
good indicator of regional origin. The relatively high δ
15
N
collagen
values
in Elmina support the archaeological evidence for reliance on marine
dietary sources. North American sites in this study do not include
coastal locations where marine dietary input would be equally high.
Without this direct comparison, one cannot conclude that nitrogen
isotopes are regionally distinct between Africa and all of North Amer-
ica. Rather, nitrogen isotopes are controlled more likely by local food
sources, and to some extent, social class (France et al., 2014).
The results of this study indicate that oxygen isotope values are
particularly useful for distinguishing Africans from North Americans.
δ
δδ
FIGURE 3 Collagen nitrogen and
carbon isotope values compared between
Elmina and Euro-Americans (top), and
Elmina and African Americans (bottom).
Closed symbols represent bone values;
open symbols represent tooth values
FRANCE ET AL.15

TABLE 3 Statistical results
Elmina Walton Woodville Congressional Hilleary Kincheloe Foscue Glorieta FABC Parkway Robinson Pettus AP Hill
Elmina <0.001 0.021 <0.001 <0.001 0.048 0.159 <0.001 0.007 0.003 0.038 <0.001 0.012
Walton <0.001 <0.001 <0.001 0.022 0.029 0.003 <0.001 0.119 0.012 0.001 0.232 0.021
Woodville 0.008 0.014 0.835 0.108 0.071 0.476 0.284 0.257 0.126 0.931 0.005 0.257
Congressional <0.001 0.002 <0.001 0.070 0.021 0.405 0.162 0.134 0.074 0.599 0.001 0.175
Hilleary <0.001 0.603 0.043 0.016 0.044 0.048 0.386 0.808 1.000 0.065 0.279 1.000
Kincheloe 0.392 0.029 0.429 0.021 0.044 0.133 0.022 0.133 0.095 0.095 0.044 0.133
Foscue 0.005 0.065 0.257 0.007 0.109 0.133 0.116 0.200 0.111 0.730 0.008 0.057
Glorieta <0.001 0.009 0.347 <0.001 0.037 0.137 0.804 0.456 0.285 0.158 0.014 0.600
FABC 0.002 0.143 0.038 0.757 0.214 0.133 0.114 0.082 1.000 0.032 0.461 0.886
Parkway 0.004 0.265 0.537 0.008 0.354 0.381 0.905 0.961 0.111 0.016 0.354 0.905
Robinson 0.843 0.023 0.126 0.001 0.065 0.381 0.190 0.032 0.032 0.095 0.003 0.111
Pettus 1.000 0.003 0.081 <0.001 0.007 0.533 0.109 0.007 0.016 0.045 0.943 0.368
AP Hill 0.698 0.026 0.257 0.003 0.016 0.800 0.200 0.082 0.057 0.111 1.000 0.933
Elmina Walton Woodville Congressional Hilleary Kincheloe Foscue Glorieta FABC Parkway Robinson Pettus AP Hill
Elmina <0.001 <0.001 <0.001 <0.001 0.027 0.022 0.510 0.002 <0.001 0.001 <0.001 0.011
Walton <0.001 0.285 0.334 0.147 0.725 0.023 <0.001 0.277 0.836 0.043 0.002 0.143
Woodville 0.014 0.001 0.155 0.074 0.643 0.177 <0.001 0.038 0.329 0.662 0.043 0.257
Congressional <0.001 0.002 <0.001 0.409 0.972 0.022 <0.001 0.651 0.303 0.016 <0.001 0.101
Hilleary <0.001 0.617 0.034 0.032 0.914 0.032 <0.001 0.525 0.198 0.098 0.015 0.179
Kincheloe 0.184 0.106 1.000 0.067 0.237 0.190 0.022 1.000 1.000 0.190 0.044 0.533
Foscue 0.002 0.052 0.052 0.008 0.159 0.857 0.077 0.063 0.095 0.151 0.435 0.556
Glorieta <0.001 0.011 0.815 <0.001 0.059 0.907 0.409 0.001 <0.001 <0.001 0.003 0.023
FABC 0.002 0.119 0.067 0.905 0.104 0.267 0.190 0.073 0.190 0.016 0.004 0.343
Parkway 0.164 0.231 0.931 0.011 0.245 0.857 0.841 0.724 0.063 0.056 0.002 0.286
Robinson 0.176 0.003 0.126 <0.001 0.008 0.190 0.056 0.020 0.032 0.151 0.622 0.286
Pettus 0.009 0.025 0.755 <0.001 0.100 1.000 0.435 1.000 0.032 0.943 0.065 1.000
AP Hill 1.000 0.003 0.019 0.002 0.006 0.267 0.016 0.013 0.029 0.190 0.556 0.073
Note: All values are p-value results from Mann–Whitney tests. Comparisons are considered statistically significant if p< .05. Significant differences are highlighted in bold. ( )δ
15
N
collagen
;( )δ
13
C
collagen
;( )
δ
18
O
carbonate
;( )δ
13
C
carbonate
.
16 FRANCE ET AL.

The Elmina population, which represents a mix of West African peo-
ple, shows oxygen isotope values that are distinct from a majority of
North American values in this study. Remains from Glorieta Pass
(Figure 2), a military company mustered out of Texas, are the excep-
tion. As one of the southern-most points in the United States, this
area shows some of the most positive North American δ
18
O values in
meteoric water. As noted, Elmina essentially represents the lowest
expected oxygen isotope values in exported African slaves whereby
δ
18
O values for other exported slave populations are expected to be
higher than or approximately equal to Elmina values. Individuals living
for years in the southern-most regions of North America may show
some oxygen isotope overlap with recently arrived Africans from Sen-
egambia, Sierra Leone, Liberia, Ghana or the Bight of Benin (Figure 1).
However, recently arrived Africans from further south (i.e., Bight of
Biafra, western Central Africa, and Southeast Africa) should be isoto-
pically distinct from North American populations. Oxygen isotopes in
southeastern regions and all central and northern regions of North
America potentially could be used to identify recent arrivals from
Africa.
Of particular interest are North American sites with enslaved Afri-
can Americans from the mid- to late-1700s: A.P. Hill, Pettus, and Rob-
inson Cemetery. Values from the Pettus and Robinson skeletal
remains show average δ
18
O
carbonate
statistical differences from values
of several other sites, including both Euro-Americans and African
Americans, while the average value for A.P. Hill individuals is statisti-
cally similar to almost all North American sites. Most individuals from
these sites show δ
18
O
carbonate
values ~2‰less than the Elmina aver-
age. Similarly, individuals from Parkway Gravel, representing slaves or
former slaves in the later 1800s, and Elmina show no overlapping
δ
18
O
carbonate
values. Rather, Parkway Gravel remains show
δ
18
O
carbonate
values typical of its North American location. This obser-
vation suggests that these individuals were born in North America or
spent the majority of their lives there. It is notable that the two Afri-
can American sites containing both tooth and bone data (Parkway
Gravel and Robinson Cemetery) show similar δ
18
O
carbonate
values
between the two tissue types. This supports the idea that these adult
bone isotope values reflect a lifetime spent in North America, rather
than values integrated through a forced migration. Teeth from African
Americans were limited in this study, but this small subset of data
lends credence to the idea that slaves were often born into the sys-
tem by the early 1800s.
Three notable outliers with relatively higher δ
18
O
carbonate
values
were observed among African Americans in this study: two individuals
from Pettus (44JC33-PETTUS-191 and 44JC33-PETTUS-253) and
one from A.P. Hill (44CEAPHILL-VAOCME-2). These three individuals
show δ
18
O
carbonate
values that are more similar to the majority of
Elmina values (Figure 2). These outliers may have been recent arrivals
to the North American Mid-Atlantic from Africa, or alternatively, were
born in the furthest southern states (i.e., Florida, Alabama, Georgia, or
Louisiana) or the Caribbean. These two sites contain some of the ear-
lier remains likely from the late 1700s (Pettus) or earliest 1800s (A.P.
Hill) when the slave trade was still quite active. Others from these
sites appear to have been in North America for most of their lives.
This preliminary case study demonstrates how an isotopic
approach potentially can explore slavery as a self-sustaining system in
North America, identifying a reduced influx of new individuals in the
mid- to late-1800s. To comprehensively test this idea, additional iso-
tope testing of African and North American archaeological remains is
required, coupled with detailed analysis of age to facilitate interpreta-
tion of individual residency duration. While some overlap between
African and far southern North American sites may become apparent
in future studies, these data offer insight for identifying regional ori-
gins and numerical representation of African peoples in the North
American diaspora.
While this study did not directly test isotope values from Central
American and Caribbean individuals, previous research provides an
isotopic comparison for this region which was active in the slave trade
to North America. Local δ
18
O
carbonate
values from human remains in
these regions ranges from approximately +25 to +29‰, with most
values in the range of about +27 to +29‰(Laffoon et al., 2013, 2018;
Price et al., 2010, 2012; Schroeder et al., 2009). This is significantly
higher than the North American values in this study, but it does over-
lap with the Elmina values. This implies that oxygen isotope values
may be able to distinguish recent arrival in the mid-Atlantic region,
but distinction between a Caribbean origin and a more northern Afri-
can origin may be confounded without additional data, such as stron-
tium isotopes. However, origin from more central or southern Africa
may be distinguishable, although additional data sets are necessary to
test this. Both δ
13
C
carbonate
and δ
13
C
collagen
values from Central Ameri-
can and Caribbean locals and recent migrants show a range of values
including dominantly C3 consumption to dominantly C4 consumption
(Bastos et al., 2016; Laffoon et al., 2013, 2018; Price et al., 2012;
Schroeder et al., 2009). The relative δ
13
C relationship between local
individuals and confirmed migrants from Africa (i.e., which group con-
sumed more C4 plants) varies, likely depending on the dominant food
base in the region of birth. With additional future analyses from Afri-
can archaeological remains, the δ
13
C and δ
18
O values may be coupled
to provide a more precise region of origin and distinguish between
the African and Caribbean slave trading routes, both of which were
active until the legal cessation of this practice.
6|CONCLUSIONS
The African diaspora contributed significantly to the cultural and bio-
logical make-up of the larger colonial population of the United States
of America, with estimates of the number of enslaved persons
brought to North America from Africa varying from approximately
208,000 to 370,000 (Curtin, 1969; Lovejoy, 1989; Voyages: The
Trans-Atlantic Slave Trade Database, 2017). Exact numbers and
knowledge of the precise origins of these individuals are limited to
incomplete historical and bioarchaeological records. The unique stable
isotope profile of West Africans presented in this study facilitates the
identification of recent arrivals in a number of archaeological Mid-
Atlantic sites, potentially enabling increased understanding of the
slave trade and in turn, African American population dynamics.
FRANCE ET AL.17

This study presents a rare direct comparison between 18th- and
19th-century North Americans and Africans from the relatively cos-
mopolitan site of Elmina, Ghana to determine whether oxygen iso-
topes can be used to identify recently arrived Africans, and thus shed
light on patterns of arrival into North America. Isotope values of indi-
viduals from Elmina serve as a proxy for isotope values of individuals
exported from Africa since the values from Elmina are distinct from
most North American populations, with the exception of extremely
southern locations and the Caribbean. While results are considered
preliminary due to available sample sizes, comparison to North Ameri-
can slave population samples from specific archaeological sites sug-
gests that by the mid-1700s the North American slavery system may
have been largely self-sustaining, with the majority of individuals born
and raised in North America. Further broad comparison of carbon and
nitrogen isotope values confirms their utility in discerning dietary
resources, specifically a high influence of C4 vegetation and marine
resources in Elmina.
Extrapolation of these data to the larger African continent may be
possible with additional contributions and future analyses. With the
current data it is not possible to discern precisely where in Africa the
individuals living in Elmina originated, although it is known that this
site attracted immigrants from disparate locations within a restricted
geographical region based on the homogeneity of δ
18
O
carbonate
values
with few outliers. Stable isotope data from African archaeological
remains are limited for 17th–19th-century individuals, but this study
demonstrates the potentially useful applications should such remains
become available. With a more comprehensive data set from North
America as well, it may be possible to distinguish African regional ori-
gins of North American enslaved individuals, which would provide a
new window into the cultural components carried to the new world
via the Atlantic slave trade.
ACKNOWLEDGEMENTS
Archaeological research at Elmina and analyses of the Elmina skeletal
material has been undertaken with the permission of the Ghana
Museums and Monuments Board. Janet Monge facilitated access to
the Elmina collection while it was housed at the University of Pennsyl-
vania Museum of Archaeology and Anthropology. Scott MacEechern
facilitated research on the Elmina skeletal material while it was
housed at Bowdoin College. Access to comparative series was autho-
rized by: the Association for the Preservation of Historic Congressio-
nal Cemetery, Washington, DC; Nicholas Bellantoni, Connecticut
State Archaeologist, Storrs, CT; C. Clifford Boyd and Donna Boyd,
Radford University, Radford, VA; Kathy Child, R. Christopher
Goodwin & Associates, Inc., Frederick, MD; Franklin Damann and
Brian Spatola, Anatomical Division, National Museum of Health and
Medicine, Silver Spring, MD; Charles Ewen, East Carolina University,
Greenville, NC; Chuck Fithian, Division of Historical and Cultural
Affairs, State of Delaware, Dover, DE; Collections Advisory Commit-
tee, Department of Anthropology, National Museum of Natural His-
tory, Smithsonian Institution, Washington, DC; Nicholas Luccketti and
Garrett Fesler, James River Institute for Archaeology, Inc.,
Williamsburg, VA; Yvonne Oakes, Museum of New Mexico, Santa Fe,
NM; Virginia Office of the Chief Medical Examiner. The Rice Endow-
ment for Forensic Anthropology, and Smithsonian Museum Conserva-
tion Institute Federal and Trust funds supported this project.
C. Doney, D. Dunn, A. Lowe, S. McGuire, S. Mills, W. Miller, and
A. Warmack assisted with procurement and preparation of remains
and also supported by NSF REU Site Grant SMA-1156360.
DATA AVAILABILITY STATEMENT
This manuscript and data therein will be available upon final publica-
tion in the Smithsonian Research Online Database (https://research.
si.edu).
ORCID
Christine A. M. France https://orcid.org/0000-0001-9133-9058
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Supporting Information section at the end of this article.
How to cite this article: France CAM, Owsley DW,
Bruwelheide KS, Renschler ES, Barca KG, DeCorse CR. Stable
isotopes from the African site of Elmina, Ghana and their
usefulness in tracking the provenance of enslaved individuals
in 18th- and 19th-century North American populations. Am
J Phys Anthropol. 2019;1–21. https://doi.org/10.1002/ajpa.
23946
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