Abstract
This paper presents the results of stable carbon (
Keywords
Introduction
The communities of Bronze Age Anatolia witnessed the formation of larger and more densely organized settlements with more centralized governance structures. By the later Middle Bronze Age (MBA) and Late Bronze Age (LBA) of the second millennium BCE, these had either become woven into, or the people were at least certainly aware of, the first Anatolian empires, notably that of the Hittites (Bachhuber, 2012; Bryce, 2005, 2011; Glatz, 2009; Özdoğan, 2023; Roosevelt and Luke, 2017). The Aegean world, to the west, also saw the rise of the regionally powerful Minoans and Mycenaeans (Mountjoy, 1998). Region-specific leadership exerted control and influence over their immediate and larger territorial landscapes from large settlement centres. As part of these control structures, extensive agricultural systems that included field agriculture (i.e. predominantly cereal crops) and animal husbandry (including ante-mortem product exploitation) became more common, and these agricultural and staple finance economic systems were integrated into networks of exchange in goods such as metals and ceramics, and likely also textiles (Bachhuber, 2012; Diffey et al., 2020; Özdoğan, 2023; Roosevelt and Luke, 2017; Styring et al., 2017). The beginnings, subsequent developments, and intensified structure of deliberate and focussed animal management and crop cultivation is a defining part of human history.
The consequences of these overlapping strategies included radical changes in the dynamics between human societies and the natural world resulting in incalculable impacts not only on past human societies but also their environments (Goudie, 2019). In this context it is, therefore, important to understand how these Bronze Age settlements and their respective mechanisms of management leveraged local landscapes, agriculture, and agricultural systems to provide for increasingly large and diverse populations. Whilst there has been an abundance of research in the region, MBA and LBA agricultural systems (including animal management and husbandry) in western and central Anatolia remains poorly understood, with research so far privileging centres such as Troy and Hattusa (Marston et al., 2022 − for Hattusa see Diffey et al., 2020, Von Den Driesch and Pöllath, 2004 − for Troy see Riehl, 1999; Riehl and Marinova, 2008; Uerpmann, 2003). Excavations and environmental research at the Bronze Age site of Kaymakçı in western Anatolia are providing an important focus to address this deficit (see Irvine et al., 2024; Marston et al., 2022; Roosevelt et al., 2018; Shin et al., 2021; Slim et al., 2020;). This study aims to contribute further to rectifying this gap in regional understanding. Here we use stable carbon and nitrogen isotope analysis of faunal osteological material (on extracted bulk bone collagen) from stratigraphic excavations at Kaymakçı to investigate human-environment and human-biome interactions around the site, focussing on animal management and husbandry, in particular. We demonstrate that the data from Kaymakçı confirms the importance of micro-regional analyses in assessing the dynamics of Mediterranean river basins with diverse ecological niches, including wetlands, plains, and mountainous uplands. We show that the Kaymakçı community benefitted from and expanded on such proximate variation.
This study is just one part of the larger joint German Archaeological Institute-Koç University Research Center for Anatolian Civilizations (DAI-ANAMED) ‘Humidity and Society: 8,500 Years of Climate History in Western Anatolia’ project, part of and supported by the DAI ‘Groundcheck’ research cluster. It also provides some of the first applications of stable isotope analysis to faunal osteological remains to shed light on second millennium BCE animal management practices in the region. Whilst animal management practices have been one of the more commonly investigated themes utilizing isotopic analyses in Anatolia, faunal isotopic data from western Anatolia, particularly for the MBA and LBA periods is still relatively scarce (Irvine and Özdemir, 2020; Yazıcıoğlu and Irvine, In Press). Investigating animal management practices is a key facet in permitting us to explore how human and animal populations interacted with their environments as well as providing an understanding of the economic foundations of past communities. The study of archaeological fauna allows us to gain a better understanding of the living landscapes of the past; providing proxies for past environmental conditions, insights into ecology and behaviour, as well as a better understanding of the activities and decisions of past human groups that depended on those animals (Britton, 2018; Jones and Britton, 2019).
Thus, in this study, by combining biomolecular stable isotope analysis of faunal osteological material (bulk bone collagen) in conjunction with the evidence from more traditional zooarchaeological and contextual analyses, we aim to contribute to the understanding of the lives of the Bronze Age peoples of Kaymakçı and, in particular, their animal management practices. This, furthermore, will provide us with a way to investigate the dynamics of the past economy as well as human interactions with their ecological and environmental surroundings at the site and in the immediate surrounding environs.
Site and biogeographic information
Kaymakçı is located in the Marmara Lake Basin on the northern edge of the middle Gediz River Valley in western Anatolia (Figure 1). Under the direction of the Kaymakçı Archaeological Project (KAP), excavations at the site since 2014 have revealed a primary occupation period in the second millennium BCE, with several local MBA and LBA phases ending with thorough abandonment perhaps well before the end of the 13th century BCE (Roosevelt, 2024; Roosevelt et al., 2018). There are six contemporary citadels surrounding the lake basin, and Kaymakçı is the largest with a fortified area of 8.6 ha (Roosevelt et al., 2018; Roosevelt and Luke, 2017). Inside the main citadel fortifications walls demarcate an inner citadel and other areas, and the traces of terraces and other remains suggest that there was a dispersed extramural settlement at least down to the lakeshore and surrounding plains (Roosevelt and Luke, 2017). A large part of the inner citadel appears to have served as a centralized facility, whilst decentralized storage units appear associated with structures of mixed domestic and small-scale industrial utility spread across the site (Marston et al., 2022; Roosevelt et al., 2018; Shin et al., 2021). Due to its size, location, finds, and chronology, Kaymakçı must have been a regional capital in this area, which was known to the Hittites as the Seha River Land (Roosevelt and Luke, 2017). During the LBA, this indigenous kingdom was a vassal of the Hittite Empire at some points, whilst at other times it was aligned with the regional powers of the Aegean (Beckman, 1999; Bryce, 2003; Gander, 2017; Hawkins, 1998; Heinhold-Krahmer, 1977; Meriç, 2021).

Regional map showing the location of Kaymakçı on the edge of the Marmara Lake Basin in the broader Gediz River valley. The inset shows the location of the map in western Türkiye (© Gygaia Projects).
Kaymakçı lies in the Mediterranean coastal woodland zone with a climate consisting of hot summers with humid and temperate winters, which makes it a particularly good environment for agriculture (Marston et al., 2022; Shin et al., 2021). The current landscape cover in the uplands around the site consists of open woodlands of deciduous and evergreen oak, steppe pastureland, and agricultural plots of annual crops, olives, and grapes (Marston et al., 2022). With increasing elevation, woodland density increases, as well, with pine forests dominating the mid- to upper elevations of the Bozdağ mountains along the southern fringe of the Gediz valley, for instance. Following anthracological analyses, oak species dominate the wood charcoal assemblage from Kaymakçı, and it is likely that the wooded landscape in the Bronze Age would have been similar to the current day (Marston et al., 2022). Local annual precipitation in the second half of the 20th century CE averaged 500–600 mm per year, with the summer months of June to September having the least precipitation (Marston et al., 2022; Roosevelt, 2009). Archaeobotanical research at Kaymakçı has revealed the presence of cereals, pulses, and fruits (Irvine et al., 2024; Shin et al., 2021). Cereals include barley, free-threshing wheat, einkorn, and emmer wheat, and pulses include bitter vetch, chickpea, grass pea, lentil and common vetch. Grape and fig are the only two fruits found at the site to date (Shin et al., 2021).
In the second millennium BCE, at least three major rivers, the Kumçay to the north and the Alaşehir that fed into the Gediz to the southeast, were the primary hydrological sources in the region, each fed by local mountain streams and permanent springs. In addition, historical documentation reveals that seasonal flooding created vast bodies of water in the plain, forming lake-like features for several months of the year (Çelik et al., 2024). Evidence indicates that at least one body of water, Lake Marmara, was stable throughout the year, even if waxing and waning in full extent and thus providing ideal conditions for a dynamic wetland zone. Kaymakçı sits overlooking the western edge of the lake basin. Diverse evidence confirms that the basin would have been particularly important (with regards to both agriculture and fishing) for the inhabitants of the site and other local contemporary communities; this pattern persisted through history until recent times (Luke, 2019; Luke et al., 2017; Luke, 2024; Marston et al., 2022; Roosevelt et al., 2018). In the Bronze Age this importance is demonstrated in one aspect by the evidence for fishing, in the form of carp and catfish bones and fishing equipment, including numerous bone gorges and at least one bronze fishhook (Roosevelt et al., 2018: 670, 678). There was likely an abundance of well-watered land for field agriculture with wetlands and other bodies of water in the area, some of which were spring fed, and others associated with seasonal flooding from the lake (Çelik et al., 2024; Gul et al., 2013; Irvine et al., 2024; Marston et al., 2022; Shin et al., 2021). Ethnohistorical research, too, confirms that prior to the 1950s transhumance flourished in the Gediz basin, with annual pastoral cycles between the mountain ranges (Luke et al., 2017).
Previous zooarchaeological research at Kaymakçı
Zooarchaeological research at Kaymakçı since 2014 documented more than 14,000 specimens from dry-sieved samples representing a diverse faunal spectrum of more than 40 distinct taxa from freshwater bivalves to brown bear (Marston et al., 2022; Roosevelt et al., 2018; Slim et al., 2020). Fish remains are numerous and visibly dominate the heavy fraction from floatation samples. This is not surprising given the site’s strategic proximity to Gediz wetlands. Wels catfish (
Isotope zooarchaeology: Theory and applications
Isotope zooarchaeology is now a reasonably well-established sub-field of bioarchaeological isotope studies and has been proven to be adept in clarifying complex aspects of human-environment interactions and human-animal economic, dietary, socio-political, and socio-cultural relationships (Britton, 2017; Jones and Britton, 2019; Makarewicz, 2016; Pilaar Birch, 2013; Zangrando et al., 2014). It has enhanced our ability to reconstruct the dynamics of past ecosystems, paleoenvironmental and palaeoclimatic conditions, and the economic and animal exploitation strategies employed by past humans (Jones and Britton, 2019; Makarewicz, 2016; Pilaar Birch, 2013; Zangrando et al., 2014). For shedding light on the multitude of approaches taken to animal management by past human groups isotopic analyses of domestic species has proven extremely useful, and while studies on wild animals are becoming more commonplace, the study of domestic species has continually been at the centre of bioarchaeological investigations (Jones and Britton, 2019). Isotopic analyses of teeth, micro- and macro-faunal bones (from both wild and domestic species), and shell have significantly contributed towards our ability to characterize the specific environments within the immediate environs and wider regions where archaeological sites are located (e.g. see Leichliter et al., 2017; Prendergast et al., 2017; Richards et al., 2017; Somerville et al., 2018; Worthey et al., 2022).
Faunal remains are noteworthy because their isotope values tend to reflect their ecology and the contemporary environmental locale, and their presence in the archaeological record is a direct result of human activities (Jones and Britton, 2019; Pilaar Birch, 2013; Zangrando et al., 2014). As a result, the isotope signatures of wild animals can provide evidence of animal ecology and environmental conditions (Britton, 2017; Makarewicz, 2016; Pilaar Birch, 2013; Zangrando et al., 2014). Isotopic analyses of the preserved remains of domestic animals are better fit to provide indications of anthropogenic modifications to their environments, diets, physiologies, and life-histories, including domestication, mobility, pastoralism and transhumance, foddering and feeding practices, and the compositions and sources of consumed water and vegetation (Makarewicz, 2016; Pilaar Birch, 2013; Zangrando et al., 2014).
The
The
Nitrogen isotope ratios, when applied to animals and humans, are generally used to interpret trophic level and marine resource consumption (Towers et al., 2011). The
Materials and methods
For this stable isotope study, a total of 92 faunal bone fragments were sampled. Both wild (fish, birds, deer, hare) and domestic animals (caprids, cattle, pigs, dogs) were selected for isotopic analysis. The samples come from different areas of the site and different contexts (see Figures 2 and 3 and Supplemental Material 1), but all date to local LBA phases, dating roughly between the late 18th/early 17th and 15th/14th centuries BCE, as determined by a combination of relative ceramic phasing and radiocarbon analyses (Roosevelt, 2024).

Quickbird satellite image of the citadel of Kaymakçı, showing the locations of excavation areas from which faunal remains examined in this study derive (© Gygaia Projects).

Plans of excavation areas 95.555, 97.541, 99.526, and 109.523 at Kaymakçı, showing the locations of faunal remains examined in this study (© Gygaia Projects).
For the taxonomic identification of the faunal material, an on-site reference collection was consulted, along with specialist publications including Schmid (1972), for mammals, Brinkhuizen (1989) and Radu (2005), for fish, and Cohen and Serjeantson (1996), for birds. To distinguish between sheep and goat, we followed Zeder and Lapham (2010), for postcranial bones and Zeder and Pilaar (2010), for teeth.
Prior to collagen extraction the external surfaces of the faunal bone samples were subjected to mechanical cleaning and in some instances, where necessary, they were cut into smaller pieces (ca. 3 cm in length) using a circular diamond saw. Collagen extraction of the faunal remains was performed at the ARHA (Archaeology and History of Art) laboratory of Koç University, İstanbul, Türkiye and followed a standard modified Longin (1971) protocol: demineralization of the bone samples in 0.5 M HCl (0.3 M HCl for more delicate bones such as those from the fish and birds), gelatinization in a pH 3 HCl solution at 70℃ for 48 h in a heating block, filtration using a 9 μm polyethylene Ezee-filter, followed by freezing and then lyophilization in a freeze dryer (Telstar LyoQuest Plus) for 48 h. Isotopic analysis was performed at TENMAK (Turkish Energy, Nuclear and Mineral Research Agency) on a ThermoFisher Scientific Flash EA 1112 coupled to a Delta V Plus mass spectrometer.
The reference standards used for IRMS analysis of samples at TENMAK were B2215 and IAEA-600 (
Quality control of the extracted and analysed collagen was assessed following the criteria set out by Ambrose (1990), DeNiro (1985) and van Klinken (1999), who have determined that collagen with C:N atomic ratios lower than 2.9 or higher than 3.6, %C values outside of the range of 10%−47%, and %N values outside the range of 5%−17% is likely to have been altered, contaminated, and affected by diagenesis.
Results
From the initial 92 samples, only 38 passed the ancient bone collagen quality criteria defined above. All other samples (i.e. those that did not meet the quality criteria) were discarded from further analysis and are not discussed in this paper. Two of the samples have marginally low %N values but have acceptable %collagen and %C values, as well as acceptable C:N atomic ratios (Ambrose, 1990; DeNiro, 1985; van Klinken, 1999). Only when sample values fell outside of the acceptable ranges for all three quality checks (%C, %N and C:N) were they discarded from further analysis, as C:N values in ancient collagen still remain a strong gauge of collagen preservation (Guiry and Szpak, 2021).
The full set of

δ13C and δ15N values plotted for all faunal remains from Kaymakçı examined in this study.
δ13C and δ15N means and standard deviations (SD), ranges, and minimum and maximum values of species sampled from Kaymakçı examined in this study.

Means and standard deviations of
Discussion
As can be seen from the stable isotope values (Supplemental Material 1, Table 1 and Figure 4), there is a reasonably large, and significant, spread in both
Conversely, there is a relatively tight clustering for the terrestrial herbivorous wild animals (deer and hare), with an overall range of 1.1‰ (−21.9‰ to −20.8‰) for
The patterning of the stable isotope values of the terrestrial herbivorous wild animals may also mean that we can tentatively, given the small sample size, identify a wild/natural unaffected range of terrestrial herbivorous faunal
Animal management at LBA Kaymakçı
Specific animal management and herding strategies should be expected for domestic animals in Bronze Age Anatolia. At Kaymakçı, the zooarchaeological evidence has indicated a diversity in exploitation strategies, with cull patterns suggesting a variety of practices, ranging from primary exploitation for meat procurement as well as antemortem product exploitation across, between, and within different domesticated species; seasonality in (wild and domesticated) animal exploitation is possible, as well (Fındıklar et al., 2024; Marston et al., 2022; Slim et al., 2020). The stable isotope data obtained from this study allows us to investigate animal management strategies in more detail.
Relatively, and cautiously, speaking (as there are only three sampled cattle specimens), potentially the clearest evidence we have for animal management from the stable isotope values at Kaymakçı regards the cattle. Their
There are a large number of cattle remains (NISP ca. 10%−15%) in the Kaymakçı faunal assemblage, and they were likely to have been regarded as an important species (Fındıklar, 2021; Fındıklar et al., 2024). It has been suggested, more generally, that cattle would have been prestige animals in Bronze Age Anatolia, principally related to their role as draught animals in agricultural extensification (Arbuckle, 2014). Furthermore, as only richer parts of society could likely maintain these animals, the animals themselves were a source of elite wealth having a direct financial value through their sale, rental, or exchange (Arbuckle, 2014; Kohler et al., 2018). The cattle in our dataset with the more negative
A ubiquitous presence of bitter vetch, which is often considered to be mainly a fodder crop, has been noted for the citadel areas of the site (Shin et al., 2021). One possible implication for Kaymakçı, therefore, is that bitter vetch was a highly valued and ubiquitous crop as it was either cultivated and/or strategically gathered from wetland boundaries for cattle grazing and fodder, and was thereby an important component in the overall economy and sociopolitical and socioeconomic structures (Irvine et al., 2024). However, it should be noted that for this sampled (cattle) faunal assemblage, whilst their

Linear plot of
As previously mentioned, the stable isotope values do not appear to suggest distinct management strategies for sheep and goats, and it seems possible that they would have been herded together. This is visible through the overlap in
For the pigs, the
The
One final aspect to consider about animal management strategies at Kaymakçı is the relation between the
Environment and niche exploitation
The stable isotope data presented here has demonstrated that a variety of animal management strategies were employed at LBA Kaymakçı. However, this is not unexpected as there is a diverse range in local environments, meaning that there is the potential for versatility in animal husbandry management strategies at and around Kaymakçı. Animal husbandry strategies can be heavily influenced by the environments available to past human populations; thus, studies of animal management strategies such as this one can provide insights into the ways in which particular strategies may have been adapted and tailored to the specific conditions encountered (Jones and Britton, 2019). Multiple ecological zones are open to exploitation around Kaymakçı, including oak forests, lacustrine and riparian wetlands, and open steppe woodlands (Marston et al., 2022). The isotopic analysis of wild and domestic fauna in this study would appear to further emphasize that the Bronze Age people of Kaymakçı and the Marmara Lake Basin exploited all these available ecological zones. This versatility in ecological and environmental exploitation, with regards to the agricultural economy, has also been observed in crop management and arable agricultural systems at Kaymakçı, as it likely enabled risk-averse management strategies as well as the maximization of agricultural productivity and output (Irvine et al., 2024).
Previous studies into Leporidae have determined that they are generalist herbivores with mixed diets of grasses, forbs, shrubs and succulents (Somerville et al., 2018). Additionally, their
With regards to the other terrestrial wild species examined in this study (other than the deer and European hare), there is little we can say about local environmental and ecological conditions, as we only have
Conclusion
In conclusion, we can say that the people of LBA Kaymakçı employed a variety of animal management strategies with regards to domestic species (cattle, caprids, pigs), in part due to the diverse range of environments and multiple ecological zones open to exploitation around the site. Furthermore, there does not appear to have been necessarily ‘fixed’ or homogeneous management strategies for specific species, with multiple ecological zones and strategies being exploited and employed at an intra-species level for cattle, caprids, and pigs. How representative Kaymakçı is of LBA animal management strategies in western Anatolia, and even Anatolia more generally, is currently unclear due to the relative lack of comparable data. However, one hypothetical pattern observed in the stable isotope values of this study that does seem to ring true across the larger region is distinct management strategies for cattle, with the presence of both ‘local’ cattle and other cattle that were managed differently, possibly herded and/or managed further away from the sites where they were recovered, including here at Kaymakçı. This is observed in the collated and examined
Supplemental Material
sj-xlsx-1-hol-10.1177_09596836241297077 – Supplemental material for Stable isotope analysis of faunal remains from Bronze Age Kaymakçı, Western Anatolia
Supplemental material, sj-xlsx-1-hol-10.1177_09596836241297077 for Stable isotope analysis of faunal remains from Bronze Age Kaymakçı, Western Anatolia by Benjamin Irvine, Christina Luke, Canan Çakırlar, Tunç Kaner, Rana Özbal, Şengül Fındıklar and Christopher H Roosevelt in The Holocene
Footnotes
Acknowledgements
We would like to thank the Manisa Museum Directorate and the General Directorate of Cultural Heritage and Museums of the Ministry of Culture and Tourism, Republic of Türkiye, for permissions for excavations, sampling, and analyses. We are grateful to the directors and staff of the Turkish Energy, Nuclear and Mineral Research Agency (TENMAK), Ankara, Türkiye, for their helpful responsiveness and careful analyses. For assistance and guidance in field and laboratory work, we acknowledge all participants of the 2014–2019 seasons of the Kaymakçı Archaeological Project. For assistance with the lab work at Koç University we express our gratitude to Ebru Kaner, Sevil Kandemir, Şebnem Turhan, Berfin Dolançay, and Melis Yordamlı. Several researchers have significantly contributed to the Kaymakçı dataset. We especially acknowledge the laboratory efforts of Francesca Slim in identification and analysis of the broad zooarchaeological dataset to help contextualize her MA research on pigs from Kaymakçı. Ongoing analyses of more recent collections by Safoora Kamjan and Tuğçe Yalçın will feature in future publications. Finally, it is the excavators who have made this possible, both those who live nearby as well as the seasonal team. Here our heartfelt thanks to the communities of Büyükbelen, Hacıveliler, and Tekelioğlu, and the students of the Kaymakçı team. BI acknowledges a joint DAI-ANAMED Environmental Archaeology Fellowship held during the research and data collection of this study. This research was supported by Koç University, the Merops Foundation, private donors, and the ‘Groundcheck’ research cluster of the German Archaeological Institute (DAI) through a collaborative project of the German Archaeological Institute-Istanbul and Koç University Research Center for Anatolian Civilizations called ‘Humidity and Society: 8,500 Years of Climate History in Western Anatolia’. With respect to the latter project, the authors thank Felix Pirson for the pleasant and fruitful collaboration.
And finally, thank you to the two anonymous reviewers, whose comments and suggestions helped to improve the quality of this paper
Author contributions
Funding
The author(s) received no financial support for the research, authorship, and/or publication of this article.
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References
Supplementary Material
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