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Animal mobility is a common strategy to overcome scarcity of food and the related over-grazing of pastures. It is also essential to reduce the inbreeding rate of animal populations, which is known to have a negative impact on fertility and productivity. The present paper shows the geographic range of sheep provisioning in different phases of occupation at the Iron Age site of Turó de la Font de la Canya (7th to 3rd centuries BC). Strontium isotope ratios from 34 archaeological sheep and goat enamel, two archaeological bones and 14 modern tree leaves are presented. The isotopic results suggest that sheep and goats consumed at the site were reared locally (within a few kilometres radius) during the whole period of occupation. The paper discusses the isotopic results in light of the socio-political structure of this period, as complex, strongly territorial societies developed during the Iron Age in the north-east Iberian Peninsula.
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Shipping amphorae and shipping sheep?
Livestock mobility in the north-east Iberian
peninsula during the Iron Age based on
strontium isotopic analyses of sheep and goat
tooth enamel
Silvia Valenzuela-LamasID
*, Hector A. Orengo
, Delphine Bosch
, Maura PellegriniID
Paul Halstead
, Ariadna Nieto-Espinet
, Angela Trentacoste
, Sergio Jime
Dani Lo
, Rafel Jornet-Niella
1Consejo Superior de Investigaciones Cientı
´ficas- Institucio
´Milài Fontanals (CSIC-IMF), Barcelona, Spain,
2McDonald Institute for Archaeological Research, University of Cambridge, Cambridge, United Kingdom,
3Laboratoire Ge
´osciences, CNRS- Universite
´Montpellier, UMR-5243, Montpellier, France, 4School of
Archaeology, University of Oxford, Oxford, United Kingdom, 5Department of Archaeology, University of
Sheffield, Sheffield, United Kingdom, 6Arche
´ologie des Socie
´s Me
´ennes, UMR 5140, Labex
ARCHIMEDE program IA- ANR-11-LABX-0032-01, Univ Paul-Vale
´ry, CNRS, MCC, Montpellier, France,
7Arqueovitis sccl, Avinyonet del Penedès, Spain, 8Àrea de Prehistòria i Arqueologia, Universitat de
Barcelona, Barcelona, Spain
Animal mobility is a common strategy to overcome scarcity of food and the related over-
grazing of pastures. It is also essential to reduce the inbreeding rate of animal populations,
which is known to have a negative impact on fertility and productivity. The present paper
shows the geographic range of sheep provisioning in different phases of occupation at the
Iron Age site of Turo
´de la Font de la Canya (7
to 3
centuries BC). Strontium isotope ratios
from 34 archaeological sheep and goat enamel, two archaeological bones and 14 modern
tree leaves are presented. The isotopic results suggest that sheep and goats consumed at
the site were reared locally (within a few kilometres radius) during the whole period of occu-
pation. The paper discusses the isotopic results in light of the socio-political structure of this
period, as complex, strongly territorial societies developed during the Iron Age in the north-
east Iberian Peninsula.
The Bronze and the Iron Ages in Europe witnessed increased social differentiation and territo-
riality. This is reflected in the archaeological record in changing settlement pattern (from
open-air sites on the plains to fortified sites on hills), the expansion and progressive complexity
of fortifications, and the spread of warrior equipment and weapons in some tombs. These pro-
cesses thus apparently involved a significant increase in warfare and, probably, in the
PLOS ONE | October 31, 2018 1 / 14
Citation: Valenzuela-Lamas S, Orengo HA, Bosch
D, Pellegrini M, Halstead P, Nieto-Espinet A, et al.
(2018) Shipping amphorae and shipping sheep?
Livestock mobility in the north-east Iberian
peninsula during the Iron Age based on strontium
isotopic analyses of sheep and goat tooth enamel.
PLoS ONE 13(10): e0205283.
Editor: John P. Hart, New York State Museum,
Received: May 4, 2018
Accepted: September 21, 2018
Published: October 31, 2018
Copyright: ©2018 Valenzuela-Lamas et al. This is
an open access article distributed under the terms
of the Creative Commons Attribution License,
which permits unrestricted use, distribution, and
reproduction in any medium, provided the original
author and source are credited.
Data Availability Statement: All relevant data are
within the paper. Information regarding the
specimen numbers and names are detailed in
Tables 1and 2under the tab ‘Sample’. The precise
geographic location of the present-day samples is
detailed with the UTM coordinates in Table 1.
Authors may be contacted for further details at
maintenance of boundaries between territories [18]. In the north-east of the Iberian penin-
sula (present-day Catalonia), the spread of iron technology during the 8
centuries BC
coincided with the first evidence of rectangular stone buildings, urbanism and fortifications [4,
7,9]. Iron Age animal husbandry, which did not change dramatically compared to the Late
Bronze Age [1011], was characterised by a remarkable predominance of sheep and goats and
by the small size of domestic cattle, sheep/goats and pigs [1016]. This changed only slightly in
the 3
century BC, when increased consumption of pigs and a slight increase in animal size
are attested [1014,16], coinciding in time with the expansion of urban centres in the area [9,
The site named Turo
´de la Font de la Canya (Barcelona, Spain) was an important point for
cereal storage and trade with other cultures of the Mediterranean, as suggested by the presence
of numerous subterranean ‘silos’ suitable for cereal storage, together with imports of Phoeni-
cian, Greek and other origins (Fig 1; [2022]). The site is located on a small promontory (230
m a.s.l.), about 15 km from the present-day coastline and about 40 km south-west of Barcelona
[22] (Fig 2). Its occupation spanned the 7
to 2
centuries BC, that is, from the spread of iron
metallurgy in the area to the period of the Roman conquest.
The analysis of strontium isotope ratios from tooth enamel is now a well-established
method for exploring human and animal mobility [2332]. The aim of this study is to charac-
terise the geographical range of sheep provisioning for this important site through its period of
occupation, and thus to assess its degree of connectivity regarding meat provisioning through
the Iron Age. In other words, we wanted to know whether sheep were moving as much as
other materials, such as pottery and other goods recovered from the site [22]. A previous study
on seven sheep teeth from this site suggested that sheep were reared locally [33]. The present
work significantly expands the number of sheep teeth analysed and covers different phases of
occupation, allowing us to look for variations in the geographical range of meat provisioning
through time; in this study, we also analysed a few goat teeth. In order to determine the base-
line of strontium isotope variability, archaeological bones and modern leaves collected from
trees growing on different geological units around the site were also analysed as a basis for
comparison with archaeological results.
Strontium isotope analysis
Strontium substitutes for calcium and occurs as a trace element in biogenic tissues, includ-
ing the hydroxyapatite of teeth and bones [23,3435]. The Sr isotopic ratio (
Sr) varies
in different geological formations according to the age and original rubidium (Rb) /stron-
tium (Sr) ratio of the bedrock, leading to high radiogenic
Sr ratios in old or crustal
rocks, and low
Sr ratios in young or mantle rocks [23,36]. The
Sr isotope com-
position of plants reflects the strontium isotopic ratios of the underlying bedrock, as biologic
processes involved during plant growth do not entail isotopic fractionation of strontium iso-
topes [3738]. Other factors affecting strontium ratios in plants include a significant contri-
bution of rainfall water [39] atmospheric pollution and the use of modern fertilizers [40
In the case of skeletal material, the
Sr isotope composition derives from the food and
drink ingested by the animal [4546]. The porosity of bones makes their strontium signature
susceptible to diagenetic alteration, but the isotopic signature of tooth enamel bioapatite
reflects the period of tooth formation with little subsequent change [4748]. Therefore, stron-
tium isotope ratios from tooth enamel indicate the type of geological formation from which
food and water were sourced during the period of mineralization of the tooth analysed [2338,
Livestock mobility Iron Age strontium sheep and goat tooth enamel
PLOS ONE | October 31, 2018 2 / 14
Funding: This paper was developed as part of the
research projects ‘The origins of intensive
pastoralism and the creation of cultural landscapes
in North-Eastern Spain (HumanScapes)’, which
was funded by the European Commission with a
Marie Curie Intra-European Fellowship (grant
number 330098) and the Service of Archaeology
and Palaeontology of the Culture Department of the
Catalan Autonomous Government under the
direction of HAO and PH, and the ERC-Starting
Grant 716298 ZooMWest- Zooarchaeology and
Mobility in the Western Mediterranean: Husbandry
production from the Late Bronze Age to the Late
Antiquity, funded by the European Research
Council Agency (ERCEA) under the direction of
SVL. The research also benefited from the support
of the Agència de Gestio
´d’Ajuts Universitaris i de
Recerca (2017SGR995). SJM is employed under
the LabEx ARCHIMEDE from "Investissement
d’Avenir" program ANR-11-LABX-0032-01.
Competing interests: The authors have declared
that no competing interests exist.
Geology at the site
The site of Turo
´de la Font de la Canya is located on a coastal promontory on the south-west
margin of the Catalan Coastal Range. From a geological perspective, this mountain range is
characterised by fragmented outcrops of mainly Mesozoic and Tertiary sedimentary forma-
tions overlying infra-Silurian and Varingian batholith and other Palaeozoic metamorphic
rocks [50]. The settlement is located on Miocene clays, sandstones and conglomerates and is
surrounded by Plio-Pleistocene alluvia to the west and north, and by Cretaceous limestones to
the east and south (Fig 2). In the vicinity of the site, within 10–15 km, other sedimentary (Tri-
assic sandstones, dolomites, limestones and marls) and metamorphic (Cambro-Ordovician
Micacitic slates) formations also outcrop. Further to the north-east, an extensive outcrop of
Late Hercynian biotitic granodiorite is also present.
Fig 1. Plan of the site, sections of some silos, and examples of Mediterranean imports dated from the early Iron Age (7
century BC)
and the Full Iberian Period (4
- 3
centuries BC).
Livestock mobility Iron Age strontium sheep and goat tooth enamel
PLOS ONE | October 31, 2018 3 / 14
Materials and methods
The analysed archaeological material totals 30 sheep and four goat teeth (including seven
sheep teeth previously reported [33]) from different levels of occupation and silos filled with
domestic debris. Sheep and goat identification followed usual criteria [5153]. The selected
teeth correspond to second and third molars dated from different phases of occupation of the
site: nine teeth dated from the early Iron Age (7
century BC), nine from the Middle Iron Age
centuries BC), and 16 from the Late Iron Age (4
centuries BC). Despite the
higher inter-individual variation in the enamel mineralization of the third molar in compari-
son to the second [5455], as well as the possible averaging of isotope ratios [56], third molars
were selected because they were easily identifiable even when isolated. In all cases, only fully
erupted teeth (i.e. in wear) from different individuals were chosen for analysis.
The enamel samples were prepared for strontium isotope analysis following standard prac-
tices described in previous studies [24,33,57]. The tooth enamel surface was first mechanically
abraded to remove all dentine and cementum to a depth of 100 μm using a tungsten carbide
dental burr. A transversal slice of enamel about 2mm wide was cut above the enamel root junc-
tion (ERJ) from the protoconid of each tooth using a diamond cutter disc coupled to a dentist’s
drill. On ten teeth, two more transversal slices of enamel about 2mm wide were cut at the mid-
dle and top of the tooth crown (about 9mm and 15mm from the enamel root junction) to ana-
lyse potential strontium variations during the period of enamel mineralisation. Although some
variation may occur between breeds, mineralisation of sheep third molars starts about 9–12
months, and finishes about 22–34 months [5859]. Consequently, sequential sampling allows
us to observe whether animals moved between different geological layers during enamel
mineralisation [49,56,6061]. These ten teeth were added to the seven teeth published in our
previous study [33] thus totalling 17 teeth sequentially sampled (minimum 5 teeth per
350 375 400 425 450
50510 15 20 25 30 Km
Cretaceous limestones
and dolomites
Oligocene sandstones, marls,
shales and conglomerates
Eocene conglomerates,
sandstones and marls
Late Herzynian
biotitic granodiorites
gravels and clays
Triassic sandstones, dolomites,
limestones and marls
Miocene clays, sandstones,
Mediterranean Sea
Micacitic slates
Turó de la Font de la Canya
(Avinyonet del Penedès)
Fig 2. Location of the site (star) and the sampling locations of modern tree leaves and archaeological bones used to assess the bioavailable
strontium of the different geological formations surrounding the site. The site is on a Miocene plateau surrounded by Pliocene and Pleistocene
Livestock mobility Iron Age strontium sheep and goat tooth enamel
PLOS ONE | October 31, 2018 4 / 14
chronological period). The resulting samples were transferred to a clean (class 100, laminar
flow hood) working area in the Laboratoire de Ge
´osciences (Montpellier, France) for further
preparation. This involved ultrasonic cleaning to remove adhering material and immersion in
60˚C water for an hour for further cleaning. After each cleaning phase the sample was rinsed
three times on MilliQ high purity de-ionized water. A final cleaning step, in 5% acetic acid for
half an hour in an ultrasonic bath, followed by rinsing three or four times with pure water, was
also performed in order to be sure that potential remaining diagenetic effects were removed.
Once cleaned and dried in a laminar flow hood, the samples were weighed in pre-cleaned Tef-
lon beakers. The samples were then dissolved in Teflon distilled nitric acid (8 M HNO
Strontium was collected using standard resin columns (Eichrom Sr-Spec resin) and then
loaded onto single rhenium filaments with a TaCl
activator. Total chemistry blanks were less
than 20pg and thus negligible for this study. The strontium isotope composition was deter-
mined with a solid-source thermal-ionization mass spectrometer at the Labogis of Nı
ˆmes Uni-
versity (Thermo Finnigan TRITON TI). Repeated measurements of the international standard
Sr NBS 987 gave a mean value of 0.710251±0.000018 for static analysis (2 s, n = 9).
In order to assess the variability of bio-available strontium ratios in the vicinity of the site
and surrounding geological areas, 14 modern leaves from oak, pine and strawberry trees grow-
ing on different geological formations were also analysed (see Table 1 for details, specimen
name and precise location). Six of them originated from forests protected as a natural reserve
(Natural Park of Garraf, Sant Llorenc¸del Munt i l’Obac, Montseny, and Montnegre-Corre-
dor), and eight from trees growing on non-cultivated fields far (>100m) from human activities
and rivers or streams. The field permits were granted by Diputacio
´de Barcelona. Each sam-
pling location was recorded using a hand-held GPS device. The preparation protocol was
adapted from the one described in [40]. Samples of modern leaves were crushed in a Retsch
200ZM grinder, and then weighed in pre-cleaned pressure vessels in a clean laboratory envi-
ronment. They were dissolved in Teflon distilled nitric acid (8 M HNO
) overnight at room
temperature. Further acid and a trace of H
were added, before the samples were processed
in a microwave oven at 175˚C for 20 minutes. The samples obtained were then dried overnight
on a hotplate prior to a secondary oxidation stage which repeated the whole process. The sam-
ples were converted to chloride in a solution of 6 M HCl, then dried and taken up again in 2N
prior to strontium separation using standard resin columns (Eichrom Sr-Spec resin).
Despite every effort was made to collect reliable samples from the Pleistocene sediments of
the Vallès-Penedès valley, it proved difficult due to the high degree of anthropic impact on the
landscape–buildings, agriculture–. We therefore took two bone samples from two archaeolog-
ical sites located on Pliocene and Pleistocene sediments further away to the West (Table 1) as
bone tissue absorbs the strontium signature of the burying environment [4748]. The bone
sample preparation followed the same protocol described above for enamel samples.
Modern samples
Table 1 and Fig 3 (left) show the strontium
Sr isotopic ratios obtained from the 14 mod-
ern leaf samples and two archaeological bones sourced from different geological formations
neighbouring the site. The results indicate that the strontium signature of the site is around
0.7095, and that the potential strontium variation in the surroundings of the site ranges
between 0.7089 and 0.7123. The neighbour Jurassic and Cretaceous bedrock of the Garraf
mountain displays a range between 0.7089 and 0.7090. Further to the north, the Triassic dolo-
mites gave a signal of 0.7105, and further to the north-east, the Palaeozoic granodiorites and
micacitic slates of the littoral mountains display strontium ratios between 0.7113 and 0.7123.
Livestock mobility Iron Age strontium sheep and goat tooth enamel
PLOS ONE | October 31, 2018 5 / 14
In the Vallès, the sample collected on Miocene sediments close to Palaeozoic sediments of the
Montseny gave a
Sr value of 0.7157, and the sample from the Eocene conglomerates in
the West a
Sr ratio of 0.7098. The Eocene- Oligocene marls and the Pleistocene sedi-
ments of the Catalan Central Depression had values around 0.7085 and, further to the West
(130 Km distant from Turo
´de la Font de la Canya) the Oligocene bedrock displayed values
comprised between 0.7093 and 0.7095. All these strontium ratios are consistent with other
measurements from similar geological formations in the Iberian Peninsula and elsewhere [29
Archaeological samples
Table 2 and Fig 3 show the results of the 34 archaeological sheep and goat teeth from Turo
la Font de la Canya. The vast majority of strontium
Sr isotopic ratios (n = 27), including
those for all four goats, range between 0.7091 and 0.7096, compatible with the values attested
on the Miocene sediments where the site is located. Six teeth (one of 7
century BC, two of 6
centuries BC, and three of 4
centuries BC) have values in the range 0.7086–0.7090,
which could correspond to Cretaceous sediments from the neighbouring Garraf mountains
(circa 4km away). Only one tooth dated to the 7
century BC has a value of 0.7102 (sample
Table 1. Strontium isotopic ratios (
Sr) obtained on modern tree leaves and sheep bones from different geologic formations. Coordinates ETRS89 UTM31N.
Sample W N Era Period Epoch Bedrock Species
Sr Error (2s) Geological
VI-11 329415.2 4603851.5 Cenozoic Quaternary Pleistocene Gravels with lutite matrix
and sandy banks
Sheep bone 0.708589 ±0.000004 Qvpu
GAR-5 401093.85 4578084.81 Cenozoic Neogene Late Miocene Calcarenites Evergreen
0.709226 ±0.000007 NMe
TFC 50 397472 4580693 Cenozoic Neogene Middle Miocene Clays, sandstones and
0.709508 Nmag
TFC 51 397472 4580693 Cenozoic Neogene Middle Miocene Clays, sandstones and
Oak 0.709528 Nmag
449065.3 4616603.9 Cenozoic Neogene Miocene Lenticular levels of
conglomerates with arcsic
sandy matrix
0.715757 ±0.000003 NMcga
331435.8 4635310.3 Cenozoic Paleogene Oligocene Conglometrates Oak 0.709304 ±0.000005 Pogm1
VI-98 291167.6 4611828.6 Cenozoic Paleogene Oligocene Shales and sandstones Sheep bone 0.709606 ±0.000006 POmgc4
324446.7 4630001.3 Cenozoic Paleogene Eocene-Oligocene Gray marls Pine 0.708506 ±0.000007 PEOx
380229.6 4606831.3 Cenozoic Paleogene Eocene-Oligocene Marls, limestones and
Pine 0.708541 ±0.000005 PEOmg
421143.4 4610785.2 Cenozoic Paleogene Eocene Heterometric
0.709820 ±0.000003 PEcg
GAR-6 401454.53 4578621.58 Mesozoic Cretaceous Late Cretaceous Calcareous and dolomitic Pine 0.708977 ±0.000012 CVBcd
GAR-3 405910.83 4576288.54 Mesozoic Jurassic-
Upper Jurassic-
Lower Cretaceous
Calcareous and dolomitic Evergreen
0.709063 ±0.000008 Jd
GAR-4 405910.83 4576288,53 Mesozoic Jurassic-
Upper Jurassic-
Lower Cretaceous
Calcareous and dolomitic Evergreen
0.708923 ±0.000007 Jd
GAR-1 409109.00 4575181.04 Mesozoic Triassic Middle—Late
Calcareous and dolomitic Evergreen
0.710552 ±0.000092 Tm2
443688.4 4602000.2 Paleozoic Carboniferous-
Granodiorites and
alcaline granites
0.711321 ±0.000005 Ggd
GAR-7 416507.47 4579214.7 Paleozoic Cambro-
Micacitic slates Evergreen
0.712337 ±0.000006 C¸Orp
Livestock mobility Iron Age strontium sheep and goat tooth enamel
PLOS ONE | October 31, 2018 6 / 14
37–1, SU 1549), which could be compatible with the Triassic limestone and dolomites present
further away in the Garraf (circa 10km from the site).
The 17 teeth for which sequential sampling was done display low variability along the tooth
crown (Table 3,Fig 4). Again, most teeth have strontium ratios compatible with the local Mio-
cene geology all along the tooth enamel. This indicates that most animals grazed in the vicinity
of the site all the year round, and thus suggests that herding was mainly done locally. Only
three teeth (717—6
century BC, SU1087A, 4
century BC and SU1090B, 3
century BC)
have notable differences along the tooth height (over 0.000200 between the maximum and the
Sr value, see Table 3 for details). Two of those animals grazed on an area with
strontium values compatible with the Cretaceous sediments from the neighbouring Garraf
mountains (teeth 717 and SU1087A), thus reinforcing the idea that some animals arrived to
the site from other locations. In this respect, no seasonal pattern of mobility is evidenced
between the Garraf mountains and the Plio-Pleistocene valley, but some teeth have similar
degrees of variation along the tooth crown. This is the case of teeth 32 and 33 (7
century BC)
Fig 3. Strontium isotopic ratios (
Sr) obtained from 14 modern tree leaves and two archaeological bones (green crosses), 34 archaeological sheep enamel
from Turo
´de la Font de la Canya (blue dots) and three archaeological sheep dentine from Turo
´de la Font de la Canya (red triangles). The dark orange band
indicates the strontium isotopic range of the Miocene bedrock where the site is located, and the light orange band indicates the range of the Jurassic and Cretaceous
sediments neighbour to the site. ‘GAR’ vegetal samples refer to the samples collected on the Garraf mountain area (sample codes starting with GAR on Table 1), ‘Other’
refer to all the other areas (see Table 1 for sample details).
Livestock mobility Iron Age strontium sheep and goat tooth enamel
PLOS ONE | October 31, 2018 7 / 14
as well as SU1087A and SU1090B (3
century BC, see Fig 4). This suggests that some animals
may have moved around in a similar way, although this was not the case for most animals.
Sr data of the modern vegetation and archaeological bone reflect the diversity of the
geological settings in the Catalan central coast and central depression. The samples originated
from the main geological areas around Turo
´de la Font de la Canya and provide a first over-
view of the strontium isotopic ranges from the vicinity of the site to 130 Km away to the West.
The sampling of the Pleistocene sediments of the Vallès-Penedès valley proved challenging
due to the high degree of human impact in this area, which prevented us to collect reliable
samples. The strontium results from the large majority of the archaeological samples (27 out of
Table 2. Strontium isotopic ratios (
Sr) obtained from archaeological sheep and goats enamel. Sample located at the base of each tooth, about 1mm above the
enamel root junction. In the table, ‘s/g’ refers to specimens identified as ‘sheep/goat’.
Sample code SU Tooth Species Chrono Wear stage (Payne 1987)
Sr Error (±2sigma) Reference
25–1 SU 1233 m2 inf sheep 7th BC 9A 0.709378 0.000004 This study
30–1 SU 1549 m3 inf goat 7th BC 10G 0.709418 0.000004 This study
32–1 SU 1549 m3 inf sheep 7th BC 11G 0.709218 0.000004 This study
33–1 SU 1549 m2 inf sheep 7th BC 9A 0.708935 0.000003 This study
34–1 SU 1549 m3 inf goat 7th BC 11G 0.709379 0.000004 This study
37–1 SU 1549 m3 inf sheep 7th BC 11G 0.710236 0.000005 This study
38–1 SU 1549 m3 inf sheep 7th BC 5A 0.709126 0.000008 This study
41–1 SU 1649 m2 inf sheep 7th BC 5A 0.709505 0.000004 This study
59–1 SU 1670 m2 inf sheep 7th BC 10A 0.709464 0.000004 This study
137–1 SU 1710 m2 inf sheep 6th BC 9A 0.709631 0.000004 This study
139–1 SU 1710 m3 inf sheep 6th BC 6G 0.709402 0.000004 This study
47–1 SU 1616 m3 inf sheep 6th BC 11G 0.709452 0.000008 This study
712–1 SU 1710 m3 inf sheep 6th BC 9G 0.709441 0.000015 This study
714–1 SU 1710 m3 inf sheep 6th BC 11G 0.709475 0.000004 This study
716–1 SU 1710 m3 inf goat 6th BC 6G 0.709401 0.000005 This study
717–1 SU 1710 m3 inf sheep 6th BC 11G 0.708664 0.000005 This study
718–1 SU 1710 m3 inf sheep 6th BC 11G 0.708690 0.000003 This study
719–1 SU 1710 m3 inf goat 6th BC 5G 0.709445 0.000008 This study
53–1 SU 1696 m2 sup s/g 4th-3rd BC 9A 0.709097 0.000004 This study
54–1 SU 1696 m3 sup s/g 4th-3rd BC 9A 0.709486 0.000003 This study
13–1 SU 1615 m2 sup s/g 4th BC 9A 0.709569 0.000005 This study
15–1 SU 1615 m3 sup s/g 4th BC 4A 0.709309 0.000003 This study
17–1 SU 1646 m3 inf sheep 4th BC 9G 0.709394 0.000006 This study
58–1 SU 1660 m3 inf sheep 4th BC 9G 0.708687 0.000004 This study
SU1022 SU 1022 m3 inf sheep 4th BC 2A 0.709557 Valenzuela-Lamas et al 2016
SU1030 SU 1030 m3 inf sheep 4th BC 10G 0.709430 Valenzuela-Lamas et al 2016
SU1081 SU 1081 m3 inf sheep 4th BC 6G 0.709235 Valenzuela-Lamas et al 2016
SU1087A SU 1087 m3 inf sheep 4th BC 5G 0.708894 Valenzuela-Lamas et al 2016
SU1087B SU 1087 m3 inf sheep 4th BC 6G 0.709471 Valenzuela-Lamas et al 2016
1–1 SU 1090 m2 inf sheep 3rd BC 7A 0.709622 0.000004 This study
2–1 SU 1090 m2 inf sheep 3rd BC 4A 0.709287 0.000005 This study
44–1 SU 1769 m2 sup s/g 3rd BC 5A 0.709638 0.000004 This study
SU1090A SU 1090 m3 inf sheep 3rd BC 4A 0.709592 Valenzuela-Lamas et al 2016
SU1090B SU 1090 m3 inf sheep 3rd BC 11G 0.709314 Valenzuela-Lamas et al 2016
Livestock mobility Iron Age strontium sheep and goat tooth enamel
PLOS ONE | October 31, 2018 8 / 14
34 considering the bottom slice, and 53 out of 64 considering all the samples) are compatible
with the geology immediately surrounding the archaeological site. This is consistent with
sheep and goats being reared locally in the different phases of occupation, most likely on the
Miocene sediments and Pleistocene gravels and clays of the Penedès Valley. Nevertheless, the
use of other areas of this valley (the Vallès) cannot be excluded, as the Vallès-Penedès forms a
corridor of Plio-Pleistocene alluvial sediments surrounded by older geological formations (see
text above and Fig 2, also [50]). The presence of various stone pastoral enclosures in the
Table 3. Strontium isotopic ratios (
Sr) obtained from 17 archaeological sheep and goats enamel. Samples located at the base, middle and top of enamel. Teeth
codes are the same as in Table 2.
Sample code Top Middle Base Chronology Max Min Difference
25 0.709390 0.709392 0.709378 7th BC 0.709392 0.709378 0.000014
30 0.709434 0.709386 0.709418 7th BC 0.709434 0.709386 0.000048
32 0.709153 0.709139 0.709218 7th BC 0.709218 0.709139 0.000079
33 0.708826 0.708864 0.708935 7th BC 0.708935 0.708826 0.000108
34 0.709430 0.709460 0.709379 7th BC 0.709460 0.709379 0.000081
714 0.709475 0.709387 0.709259 6th BC 0.709475 0.709259 0.000215
716 0.709401 0.709303 0.709331 6th BC 0.709401 0.709303 0.000099
717 0.708664 0.708297 0.708323 6th BC 0.708664 0.708297 0.000367
712 0.709441 0.709414 0.709398 6th BC 0.709441 0.709398 0.000044
719 0.709445 0.709450 0.709410 6th BC 0.709450 0.709410 0.000040
SU1022 0.709557 0.709537 0.709387 4th BC 0.709557 0.709387 0.000170
SU1030 0.709430 0.709432 0.709391 4th BC 0.709432 0.709391 0.000041
SU1081 0.709235 0.709274 0.709269 4th BC 0.709274 0.709235 0.000039
SU1087A 0.708894 0.708804 0.709006 4th BC 0.709006 0.708804 0.000202
SU1087B 0.709471 0.709375 0.709412 4th BC 0.709471 0.709375 0.000096
SU1090A 0.709592 0.709614 0.709566 3rd BC 0.709614 0.709566 0.000048
SU1090B 0.709314 0.709193 0.709394 3rd BC 0.709394 0.709193 0.000201
Fig 4. Strontium isotopic ratios (
Sr) of the 17 teeth sequentially sampled (top, middle and bottom of tooth
enamel). Grey dots refer to teeth dated from the 7
century BC, red dashed-lines to teeth from 6
century BC and
blue lines to teeth dated from the 4
and 3
centuries BC.
Livestock mobility Iron Age strontium sheep and goat tooth enamel
PLOS ONE | October 31, 2018 9 / 14
neighbouring Garraf mountains indicates that livestock was present in this coastal mountain
area during the first millennium BC [6265]. Interestingly, the strontium results obtained so
far at Turo
´de la Font de la Canya suggest that this human community did not pasture its
sheep and goats on the Garraf or other neighbouring mountains on a regular basis. Only six
teeth out of the 34 analysed have a strontium signature compatible with that of the Cretaceous
limestones of the Garraf, despite their proximity (circa 4 km as the crow flies). Overall, the lim-
ited variability of strontium ratios points towards local rearing of caprines rather than long-
distance trade of animals.
The homogeneity of the strontium results contrast with the diversity of imports recovered
from the site, which include Cruz del Negro pottery from the Straits of Gibraltar, Tanit figu-
rines of Punic origin, a clay mask from the central or eastern Mediterranean, and numerous
Campanian A ceramics from Italy in the levels dated from the 4
and 3
centuries BC among
others [2022]. While the possibility cannot be excluded that the sheep and goats analysed
originated from other areas with similar geology, the homogeneity of tooth values in a fairly
large sample argues against this. It seems, therefore, that sheep and goats were mainly bred
locally, and only ‘prestige’ goods (e.g. Phoenician wine, Greek pottery) arrived from distant
Overall, material cultural data suggest that Turo
´de la Font de la Canya had an active role in
the Mediterranean trade. Conversely, the results from strontium isotopic analysis on sheep
and goats suggest that animal were reared locally, and so probably on a small-scale basis, and
that caprines slaughtered at the site were mainly reared in the Penedès valley and perhaps also
the neighbouring Vallès. This local breeding of livestock may reflect (and be a consequence of)
the local socio-political context. The significant change in settlement pattern in the Late
Bronze and Iron Ages–from open-air sites located on the plains to fortified settlements located
on hills–is thought to reflect increased warfare and territoriality [1,5,7,66], while weapons in
some tombs and severed heads at several sites suggest the existence of a military elite at this
time [1819]. Perhaps, even if long-distance maritime trade flourished during the Iron Age
across the Mediterranean, long-distance terrestrial movements of livestock were difficult in the
north-east Iberian Peninsula at this time.
This study has established baseline strontium isotopic ratio (
Sr) values for the vicinity of
the Iron Age site of Turo
´de la Font de la Canya (Barcelona, Spain) and surrounding geological
areas, based on analysis of modern leaves from trees growing on different geological substrates
around the site and two archaeological bone samples. Modern leaves provided a consistent
and fairly narrow range of local strontium ratio values. This new baseline has been central for
the interpretation of the strontium isotopic ratios measured in 34 archaeological sheep and
goat tooth enamel samples dated from the 7
to 3
centuries BC, to explore the geographical
range of meat provisioning at Iron Age Turo
´de la Font de la Canya. Seventeen of these sam-
ples were sequentially analysed to observe variations along the tooth crown. The investigated
archaeological samples indicate limited variability of strontium values throughout the occupa-
tion of the site, and 27 of the 34 samples are compatible with the local geology (
Sr range:
0.7091–7096), while seven samples may be derived from bedrocks as close as 5 km from the
site (
Sr: 0.7086–0.7090), and one more (
Sr: 0.7102) is compatible with slightly
more distant (about 15 km from the site) geological areas. The sequential sampling suggests
that most animals were reared locally all the year round, thus supporting the idea of small scale
herding rather than long-distance sourcing. Interestingly, some animals display similar pat-
terns of variation along the tooth crown, thus suggesting that some movement of livestock
Livestock mobility Iron Age strontium sheep and goat tooth enamel
PLOS ONE | October 31, 2018 10 / 14
existed. Overall, the archaeological results suggest that sheep and goats slaughtered at the site
were mainly reared in the local area, most notably the Miocene clays and Plio-Pleistocene allu-
vial sediments of the plain. This contrasts with the role of the site as central point for cereal
storage (see Fig 2) as well as the diversity of imports recovered at the site, which suggests that
only ‘prestige’ goods (e.g. Phoenician wine, Greek pottery)–rather than animals–were brought
to this storage-rich site. It further suggests that crop rather than livestock surpluses financed
participation in supra-regional exchange.
The low diversity of strontium ratios of sheep and goats at Turo
´de la Font de la Canya
implies herding over a limited geographical range that may partly have been dictated to the
difficulty of long-distance terrestrial movements in the Iron Age, as a result of the emergence
of the small, strongly defended territories suggested by the settlement pattern, architecture and
finds of weapons. Alternatively, the limited geographical scale of herding may primarily reflect
the rearing of livestock in only modest numbers. Further zooarchaeological studies, both mac-
roscopic and isotopic, may clarify which of these rival explanations is more plausible.
The authors are grateful to J. Evans and three other anonymous referees for their comments
on the paper, and to P. Verdoux for his technical expertise during TIMS Sr analyses.
Author Contributions
Conceptualization: Silvia Valenzuela-Lamas, Hector A. Orengo.
Data curation: Silvia Valenzuela-Lamas.
Funding acquisition: Silvia Valenzuela-Lamas, Hector A. Orengo.
Investigation: Silvia Valenzuela-Lamas, Hector A. Orengo, Dani Lo
Methodology: Delphine Bosch.
Project administration: Silvia Valenzuela-Lamas, Hector A. Orengo.
Resources: Silvia Valenzuela-Lamas, Ariadna Nieto-Espinet, Dani Lo
Supervision: Hector A. Orengo, Delphine Bosch, Paul Halstead, Dani Lo
Validation: Delphine Bosch, Maura Pellegrini, Paul Halstead, Dani Lo
Visualization: Ariadna Nieto-Espinet.
Writing – original draft: Silvia Valenzuela-Lamas, Hector A. Orengo, Delphine Bosch, Maura
Pellegrini, Paul Halstead, Dani Lo
Writing – review & editing: Silvia Valenzuela-Lamas, Hector A. Orengo, Delphine Bosch,
Maura Pellegrini, Paul Halstead, Ariadna Nieto-Espinet, Angela Trentacoste, Sergio Jime
´n, Dani Lo
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... These values are in close agreement with those recorded in other samples of Pleistocene and Miocene sediments from other places (e.g. Evans et al., 2007;Scheeres et al., 2013;Valenzuela-Lamas et al., 2018;Voerkelius et al., 2010). ...
... Three enamel samples -CR6, CRV09-285 (1) and CRII-223 (nd)are consistent with the local strontium signature, whereas the other three (CRV09-294, CRV05-79 (2), CRV05-103) probably originate from another location. The only study mapping the bioavailable strontium in the central Catalan area (Valenzuela-Lamas et al., 2018) has registered values higher than 0.71101 on Middle Upper Palaeozoic sediments and Mesozoic metamorphic rocks, which occur about 15 km from the site, in both the Littoral mountain range and the pre-Littoral mountain range, which marks the limit of the Vallès-Penedès valley in which Can Roqueta lies. ...
... Conversely, three individuals (CRV09-294, CRV05-79 (2) and CRV05-103) present higher strontium values (0.7111-0.7126). Based on the local bioavailable strontium sampling as well as on other values drawn from the literature (Scheeres et al., 2013;Valenzuela-Lamas et al., 2018;Voerkelius et al., 2010), these strontium ratios correspond with those detected in relation to Triassic sediments. Within a 200-km radius of the site, Triassic sediments are present in the nearby Collserola mountain as well as in the Montseny, Albera-Serra de Rodes, and the Montagne Noire in France (Fig. 2). ...
... Thus, archaeological mobility studies commonly use other proxies over bulk bedrock to characterise the bioavailable 87 Sr/ 86 Sr composition of an area of interest. These range from modern environmental samples, such as waters, plants and soils (Evans et al., 2010;Evans and Tatham, 2004;Frei, 2011, 2013;Sarasketa-Gartzia et al., 2018;Valenzuela-Lamas et al., 2018), over modern and archaeological faunal remains, such as rodents, snail shells and mammal teeth (Díaz-del-Río et al., 2017;Frei and Frei, 2011;Frei and Price, 2012;Price et al., 2002;Sarasketa-Gartzia et al., 2018), to human archaeological bones Nafplioti, 2011;Sorrentino et al., 2018;Triantaphyllou et al., 2015). Which of these proxies is best suited to characterise bioavailable 87 Sr/ 86 Sr reference baselines of an area of interest for provenance and migration studies of ancient humans and animals is still heavily debated as they characterise different parts of the Sr cycle and are likely biased towards the dietary 87 Sr/ 86 Sr that was available to ancient animals and/or humans (Frank et al., 2021a(Frank et al., , 2021bFrei et al., 2022;Frei and Frei, 2013;Grimstead et al., 2017;Ladegaard-Pedersen et al., 2020;Maurer et al., 2012;Price et al., 2002;Ryan et al., 2018). ...
... While the increased use of bioavailable Sr isotopes within archaeology and food science have resulted in a spike of bioavailable 87 Sr/ 86 Sr data for many parts of Spain (Díaz-del-Río et al., 2017;Guede et al., 2018Guede et al., , 2017Hoogewerff et al., 2019;Merner, 2017;Ortega et al., 2021Ortega et al., , 2013Prevedorou et al., 2010;Sarasketa-Gartzia et al., 2018;Valenzuela-Lamas et al., 2018;Voerkelius et al., 2010), no extensive bioavailable 87 Sr/ 86 Sr data set exists for southern Almería to date, despite the area being home to many active archaeological excavation sites and some of Europe's most technologically advanced horticultural zones. Hence, the main aim of this study is to construct a first bioavailable Sr isotope baseline for this region as a reference tool for archaeological mobility studies and wild flora. ...
... The use of modern environmental samples as proxies for constructing bioavailable Sr baselines for archaeological mobility studies has many advantages, the most important being that they are generally readily available and can therefore be used to cover wide geographical extents. For many, this outweighs their drawbacks, such as sensitivity to modern human activity, resulting in an increased application of plants, soil leachates and waters in baseline studies (Evans et al., 2010;Frank et al., 2021a;Ladegaard-Pedersen et al., 2020Valenzuela-Lamas et al., 2018;Wang and Tang, 2020). However, the use of soil leachates solely to constrain bioavailable Sr isotope baselines for ancient mobility studies is controversial, as no consensus exists on the soil leaching procedure. ...
The Spanish region of Almería is well known for its rich geological records and its richness in archaeological remains. Sr isotopes have been applied in archaeology as a powerful tracing tool for individual human and animal mobility, but their application requires extensive regional baselines as reference against which the target materials can be compared. This study presents Sr concentrations and ⁸⁷Sr/⁸⁶Sr values of modern environmental proxies (plants, soils and surface waters) from southern Almería to establish such a bioavailable Sr isotope baseline for this region. Additionally, this study evaluates differences in bioavailable ⁸⁷Sr/⁸⁶Sr signatures of the plants, soil leachates and surface waters and tests three soil leaching agents, ultrapure water (mq), 1M NH4NO3 and 0.1M HNO3, to better understand variations of Sr isotope signatures captured by the different proxies and to evaluate their suitability for baseline constructions. Our results define a wide range of ⁸⁷Sr/⁸⁶Sr values ranging from 0.70836 to 0.71630. Our data reveals a strong influence of the local surface lithology on bioavailable ⁸⁷Sr/⁸⁶Sr compositions. While the plants and soil leachates generally returned similar ⁸⁷Sr/⁸⁶Sr values, surface waters from the same sites sometimes returned significantly less radiogenic values likely due to transported, carbonate-derived Sr from their catchment areas. The different soil leaching procedures returned leachable fractions with similar ⁸⁷Sr/⁸⁶Sr values, but a slight bias was observed for soils with a carbonate component signifying the overall strong control of bioavailable Sr by carbonates. We propose to define bioavailable Sr isotope baselines as the average bioavailable ⁸⁷Sr/⁸⁶Sr ratio ± double standard deviation (x̅± 2σ) of 1) plants and soil leachates and 2) surface waters for each surface lithology. The soil and plant-based baselines define the narrowest range in ⁸⁷Sr/⁸⁶Sr for areas dominated by Cenozoic volcanic rocks while the widest range is seen in areas dominated by high grade Palaeozoic metamorphic rocks. Due to the scarcity of surface water run-off in the arid region of southern Almería, surface water based ⁸⁷Sr/⁸⁶Sr baselines could only be defined for sites dominated by Cenozoic sediments and high grade Palaeozoic metamorphic rocks.
... Larger teeth provide more enamel for sampling and correspond to a longer span of time that can be recorded from each sample. As a result, molar teeth are most often used for stable isotope analysis (e.g., Balasse 2002Balasse , 2003Balasse et al., 2009Balasse et al., , 2012aBalasse et al., , 2012bBalasse et al., , 2013Balasse et al., , 2017Buchan et al., 2015;Henton et al., 2010;Isaakidou et al., 2019;Trentacoste et al., 2020;Valenzuela-Lamas et al. 2018;Zazzo et al., 2005Zazzo et al., , 2010Zazzo et al., , 2012. ...
... M2 vs. M3) is more easily done for mandibular teeth than for maxillary teeth. Although some stable isotope studies have analyzed maxillary molars (e.g., Balasse et al., 2013;Trayler and Kohn, 2017), most studies rely on mandibular molars because of their abundance and ease of analysis (e.g., Balasse et al., 2009;Reade et al., 2015;Valenzuela-Lamas et al., 2018). Of the studies that sample disarticulated mandibular molars, few studies have chosen M1 (e.g., Passey and Cerling, 2002;Perry et al., 2008), and the rest have sampled M2 (e.g., Balasse et al., 2012aBalasse et al., , 2012bBuchan et al., 2015;Henton et al., 2010;Humphrey et al., 2008) or M3 (e.g., Evans et al., 2019;Tornero et al., 2013;Valenzuela-Lamas et al., 2018). ...
... Although some stable isotope studies have analyzed maxillary molars (e.g., Balasse et al., 2013;Trayler and Kohn, 2017), most studies rely on mandibular molars because of their abundance and ease of analysis (e.g., Balasse et al., 2009;Reade et al., 2015;Valenzuela-Lamas et al., 2018). Of the studies that sample disarticulated mandibular molars, few studies have chosen M1 (e.g., Passey and Cerling, 2002;Perry et al., 2008), and the rest have sampled M2 (e.g., Balasse et al., 2012aBalasse et al., , 2012bBuchan et al., 2015;Henton et al., 2010;Humphrey et al., 2008) or M3 (e.g., Evans et al., 2019;Tornero et al., 2013;Valenzuela-Lamas et al., 2018). In a disarticulated assemblage M3 are more easily identifiable because they contain three horizontal cusps compared to the two horizontal cusps on M1 or M2 (Fig. 4.21) Weinreb and Sharav 1964). ...
... To date, our database includes 1635 87 Sr/ 86 Sr isotopic values from 33 publications ( Alt et al. 2016;Albizuri et al. 2019;Balsera et al. 2016;Carvalho et al. 2015, Carvalho et al. 2019Díaz-del-Río et al., 2017a;Díaz-del-Río et al., 2017b;Díaz-Zorita Bonilla et al. 2009;Díaz-Zorita Bonilla, 2013;Díaz-Zorita Bonilla et al. 2018;Díaz-Zorita Bonilla et al., 2021;García-Rivero et al. 2020;Fernández-Crespo et al. 2020a, Fernández-Crespo et al. 2020bGuede et al. 2017, Guede, 2018Lillios et al. 2015;MacRoberts et al. 2020;Merner, 2017;Ortega et al. 2013;Prevedorou et al. 2010;Saragoça et al. 2016;Sarasketa-Gartzia et al. 2018, Sarasketa-Gartzia et al. 2019Valenzuela-Lamas et al. 2016, Valenzuela-Lamas et al. 2018Valenzuela-Suau et al. 2021;Valera et al. 2020, Villalba-Mouco et al. 2020Waterman, 2012;Wright et al. 2019;Ž alaitė, 2016, Ž alaitė et al. 2018. The bulk (80 %) have been published since 2017 (Fig. 2). ...
... Ongoing extensive research programs on domestic animal mobility (e.g. Valenzuela-Lamas et al. 2018) have substantially increased reported faunal samples, previously mostly used as a contrast of human 87 Sr/ 86 Sr home ranges. As has happened in most other countries, plants, soil and water have only been recently introduced as part of archaeological approaches to past mobility. ...
We examine the quantity, contextual quality and spatial distribution of the data gathered in the strontium isotope archaeological database for the Iberian Peninsula and the Balearic Islands, an open source available as part of IDEArq (, the spatial data infrastructure hosted at the Instituto de Historia (CSIC). It has to date 1635 87Sr/86Sr values from human and animal samples, and environmental proxies recovered during archaeological research. The data has allowed us to produce the first regional and peninsular strontium isoscapes for Iberia. We discuss the benefits and limitations of approaching mobility in Iberia through 87Sr/86Sr isotope analysis and suggest directions for future collaborative research.
... Analyses of δ 13 C, δ 15 N, and N( 18 O)/N( 16 O), which represents the ratio for oxygen, abbreviated herein as δ 18 O, have similarly been used to examine signs of domestication (e.g., differences in birthing season between wild and domestic sheep) in Neolithic and Bronze Age samples [185][186][187][188][189]. Studies using either aDNA or stable isotopes [220] and multiproxy studies combining analyses of mtDNA, collagen-peptide mass fingerprinting, and/or stable isotopes [221,222] have mainly focused on examining local management techniques across various historical periods. ...
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Starting four decades ago, studies have examined the ecology and evolutionary dynamics of populations and species using short mitochondrial DNA fragments and stable isotopes. Through technological and analytical advances, the methods and biomolecules at our disposal have increased significantly to now include lipids, whole genomes, proteomes, and even epigenomes. At an unprecedented resolution, the study of ancient biomolecules has made it possible for us to disentangle the complex processes that shaped the ancient faunal diversity across millennia, with the potential to aid in implicating probable causes of species extinction and how humans impacted the genetics and ecology of wild and domestic species. However, even now, few studies explore interdisciplinary biomolecular approaches to reveal ancient faunal diversity dynamics in relation to environmental and anthropogenic impact. This review will approach how biomolecules have been implemented in a broad variety of topics and species, from the extinct Pleistocene megafauna to ancient wild and domestic stocks, as well as how their future use has the potential to offer an enhanced understanding of drivers of past faunal diversity on Earth.
... This study provides evidence, however, for an aspect of warfare that was not emphasized by ancient historians: the presence of mercenaries from beyond Sicily among the soldiers defend- Aegean or the Triassic sandstones and Paleozoic metamorphic rocks along the Catalan Coastal Range in the north-east Iberian peninsula [45,66]. Himera, Agrigento, and Syracuse all have similar δ 18 O values, ranging from approximately -5‰ to -2‰. ...
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Increased mobility and human interactions in the Mediterranean region during the eighth through fifth centuries BCE resulted in heterogeneous communities held together by political and cultural affiliations, periodically engaged in military conflict. Ancient historians write of alliances that aided the Greek Sicilian colony Himera in victory against a Carthaginian army of hired foreign mercenaries in 480 BCE, and the demise of Himera when it fought Carthage again in 409 BCE, this time unaided. Archaeological human remains from the Battles of Himera provide unique opportunities to test early written history by geochemically assessing the geographic origins of ancient Greek fighting forces. We report strontium and oxygen isotope ratios of tooth enamel from 62 Greek soldiers to evaluate the historically-based hypothesis that a coalition of Greek allies saved Himera in 480 BCE, but not in 409 BCE. Among the burials of 480 BCE, approximately two-thirds of the individuals are non-local, whereas among the burials of 409 BCE, only one-quarter are non-local, in support of historical accounts. Although historical accounts specifically mention Sicilian Greek allies aiding Himera, isotopic values of many of the 480 BCE non-locals are consistent with geographic regions beyond Sicily, suggesting Greek tyrants hired foreign mercenaries from more distant places. We describe how the presence of mercenary soldiers confronts prevailing interpretations of traditional Greek values and society. Greek fighting forces reflect the interconnectedness and heterogeneity of communities of the time, rather than culturally similar groups of neighbors fighting for a common cause, unified by “Greekness,” as promoted in ancient texts.
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We examine the possibility that expanding trans-Mediterranean trade during the Iron Age (ca. 1,000-350 BCE) has resulted in increased morphological variability among sheep from maritime sites in the southern Levant. Using geometric morphometric tools, we compared the variability in sheep astragal morphology in a port settlement on the Carmel coast (Tel Dor), a coastal settlement in the Akko valley (Tell Keisan), and an inland urban settlement in the Hula Valley (Tel Abel Beit Maacah). Our results suggest that the sheep astragali from the port settlement at Tel Dor occupy a significantly different part of shape space than the specimens examined from the two other sites. In addition, a source-sink dynamic is implied by the appearance of coastal morphotypes in the inland site, whereas unique inland morphotypes do not occur at the coastal site. This findings do not contradict the possibility of maritime importation and consequent overland spread of non-local sheep variants in the southern Levant during the heyday of Phoenician trade.
The relationship between residence, gender and mobility is central to the study of early social complexity. And yet, until recently, it was deemed as archaeologically intractable. The recent combination of strontium data and genomics with other methods has opened up entirely new possibilities for the archaeological study of human mobility, but these advances are not without problems. Theoretical framing, empirical accuracy and data interpretation remain controversial. In this paper we address the relationship between residence patterns, gender and mobility among early complex societies, combining both ethnographic and archaeological evidence. Our approach focuses on Chalcolithic Iberia, a period in which the stage for emerging social complexity was set. The possible existence of male-centered residential patterns and their possible connection with conflict, social complexity and gender inequalities is examined. The available data on strontium isotopes suggest women were more frequently buried in places different from those where they grew up, which can be linked to bilocality biased to patrilocality, especially in the so called ‘mega-sites’. While preliminary, this body of evidence opens up fresh lines of enquiry for the study of early complex societies, highlights the benefits of combining different kinds of evidence, and underlines the centrality of gender in the social analysis.
This study uses faunal and epigraphic evidence from the valley of Cabrera de Mar in present-day Catalonia (Spain) as proxies for understanding complex processes and dynamics of cultural change between the late Iron Age and early Roman times. The faunal remains indicate significant dietary change, although the epigraphic evidence implies that language—in contrast—changed at a slower pace, as shown by the use of indigenous onomastics and the continued use of the Iberian script, coin legends included. To ensure an interdisciplinary analysis, the study also discusses change as perceptible in architectural remains, ceramics and funerary practices. Our study shows that cultural change can take place at different levels and according to different rhythms, not only on regional and settlement planes but also at neighbourhood and household scales. Finally, our results highlight the value of archaeology as a tool for studying and understanding colonial encounters.
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El jaciment protohistòric de Font de la Canya és un jaciment emblemàtic de la recerca arqueològica del Penedès i de Catalunya. Amb una seqüència de 15 anys de campanyes d’excavacions consecutives (1999-2014) ha proporcionat un volum de dades excepcional, en qualitat i quantitat, les quals, sens dubte, representen una aportació cabdal al coneixement de la primera edat del ferro i l’època ibèrica.
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The use of isotopic analysis in human and animal remains from the Holocene has proved to be a very useful tool to explore the exploitation and adaptation of past populations to different environments. In this study we present isotopic analysis results of carbon, nitrogen and strontium from the Late Neolithic- Chalcolithic site of San Juan cave (Loarre, Spain). We analysed 33 humans, divided in adult and subadult groups, and 16 animals recovered from the same archaeological context. Stable isotope analysis of carbon and nitrogen has allowed to distinguish an homogeneous subsistence pattern during the Late Neolithic- Chalcolithic transition. The use of strontium isotopes (87Sr/86Sr) in human dental enamel suggests 19% (4 out of 21) are non-local individuals, based on comparison with the local bioavailable 87Sr/86Sr range calculated using microfauna teeth from the archaeological context, modern plants and snails. This new study gives information about Late Neolithic communities located in the north-east of the Iberian Peninsula, and it allows inference of the socio-economic structure, territorial mobility and individual provenance of humans.
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With the conquest of the Iberian Peninsula by the Roman Empire, the different societies in the north, north-west, north-east, east, and centre were grouped into the same province, Hispania Tarraconensis. This article sets out to assess whether this new, Roman, territorial organization affected previous animal husbandry and hunting practices. The taxonomic and osteometric study of faunal remains from ninety-four sites dated between the fifth century bc and third century ad provides an overview of animal husbandry and hunting before and after the Roman conquest. It shows that important changes took place and that this province was differentially exploited in terms of animal husbandry.
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A 6-month experiment reports on the 87Sr/86Sr, 1/Sr, Ca/Sr and K/Rb ratios of soil materials, rainwater, soil solutions after percolation through the upper horizon of an alluvial substrate covered by grass, and of the leaves and roots from grass. A correlation between the 87Sr/86Sr and 1/Sr ratios of the rainwater, soil materials, soil solutions, and grass roots suggests an interconnected supply. Only the data point of the grass leaves plots outside this correlation, suggesting a mix for the Sr, namely from rainwater and soil materials with a different combination. On top of the rainwater supply to the leaves, 0.25 μg/g Sr from atmospheric dust with an 87Sr/86Sr ratio of 0.7105 is suspected. Based on the Sr contents and 87Sr/86Sr ratios, the grass roots take up 72 % of Sr from soil solutions and 28 % from rainwater in the case of a dominant interaction between soil solutions and rainwater. If the soil materials and soil solutions are considered dominant in the interaction with the roots, 67 % of the Sr comes from formers and 33 % from latters. If the plants do not only take up but also contribute to the interactions, the feedback represents 33 % of the uptake. In combining the 87Sr/86Sr and Ca/Sr ratios of the different contributors to the soil/plant/rainwater interactions, 7.4 times more Ca is supplied to the plants by the soil solutions than Sr, its trace equivalent. In the detail, the roots take up 2.4 times more Ca than Sr and the leaves 5.0 times more. Also, about 2.8 times more K is taken up than its trace equivalent Rb, the soil solutions releasing 2.8 times more K than Rb, the roots taking 9.0 times more K and the leaves 18.0 times more K than Rb. Also noteworthy is the fact that the grass roots pick up 2.5 times less K than the leaves compared to Ca. These values apply only to grass.
Basel-Gasfabrik (Switzerland) comprises an extensive La Tène (chiefly Lt D, 150–80 BCE) settlement and two associated cemeteries at which strontium (87Sr/86Sr) isotope analysis of human and animal teeth investigated regional and supra-regional contacts. The interpretation of the analytic data, however, requires information on the isotopic baseline values around the site. Using 102 modern vegetation and 9 water samples from 51 localities, this study characterizes the isotopic ratios of the biologically available strontium of geological units and watercourses around Basel and compares these to 28 human infant, 6 pig, and 5 dog teeth from the site. Furthermore, pedological criteria evaluate the suitability of landforms for crop and pasturelands. The 87Sr/86Sr ratios of the environmental samples from geological units in up to 50 km distance varied between 0.70776 and 0.71794. Human infant teeth exhibited much more homogeneous 87Sr/86Sr ratios (0.70847–0.70950), which coincided largely with those of potential arable soils around Basel and indicate targeted exploitation of landscapes for agriculture. The more variable values of the faunal teeth suggest more widely ranging habitats or imports from the site's hinterlands. Two local isotope ranges were defined based on archaeological enamel samples and modern vegetation data from a confined radius around Basel. The study documents the complexity of distinguishing local and non-local individuals in a geologically heterogeneous region as well as the potential of isotope analyses to explore prehistoric land-use patterns.
This special issue of the European Journal of Archaeology discusses aspects of animal husbandry in a number of provinces of the Western Roman Empire. In this introduction, we describe the general characteristics of animal husbandry in pre-Roman and Roman times to assess any changes that may have occurred after the Roman conquest. The results suggest that the territoriality typifying the first millennium bc had a significant impact on production, resulting in a decrease in cattle size and frequencies across Europe. Nevertheless, not all the regions reacted in the same way, and regional communities that focused their animal production on pigs implemented more sustainable husbandry practices over time. By bringing together studies carried out across Europe, this journal issue highlights the existence of cases of both change and continuity across the Empire, and the (uneven) impact of the market economy on animal husbandry and dietary practices in climatically different regions.
The Sr isotopic compositions (⁸⁷Sr/⁸⁶Sr) of varied organs (branches, leaves and olives) of olives trees (Olea europaea) and those of their growing environment (soils, waters, agricultural products) were determined in two distinct agricultural contexts to discuss the origin of Sr as a function of the irrigation and fertilization techniques. The two studied sites belong to the same geographic area and the same geological basement and soils, but were by subjected to different agricultural practices in terms of irrigation and supply of fertilizers and protection products. The conventional and biological agriculture modalities were defined and tested. Homogeneous ⁸⁷Sr/⁸⁶Sr ratios were measured in the various organs of the trees from a given site. However, the composition was significantly different at the two studied sites. When considering a biological agricultural modality, significant correlations are obtained between the Sr isotopic composition of the tree organs, the soils and the irrigation waters. The mobile and exchangeable fractions of the soils have identical ⁸⁷Sr/⁸⁶Sr ratios that were transferred to the trees. In case of a conventional agriculture with more intensive irrigation and spreading of plant-protection products, a clear impact of these products is visible in the soils. The ⁸⁷Sr/⁸⁶Sr ratio of the olive trees not only derives from soil sources, but also from added products with a clear role of the irrigation. A slight but noticeable foliar uptake of anthropogenic Sr is also observed. The disturbance of the soil and tree Sr isotope composition as a function of the agricultural practices is discussed in the context of using the Sr isotopic tool as a tracer of the geographic origin of olives and olive oil.