This article investigates the nature of usage, as well as the geographical origin, of a small gro... more This article investigates the nature of usage, as well as the geographical origin, of a small group of ivory artifacts recently discovered in the earliest exposed cultural depositions at the Early Islamic (650–1100 C.E.) port of Aylah (Aqaba, Jordan). In addition to explaining the finds and the significance of their context for interpreting possible historical implications, the article uses a range of techniques to learn more about the raw material. In combining archaeological, visual, and biomolecular analyses on these ivories, fresh perspectives are provided that shed new light on the infrastructure and geographical scope of late antique and early medieval trade systems. Moreover, it informs us about the economic and commercial roles played by Red Sea ports in this period and highlights the potential of analyzing organic artifacts from sites in the region to reveal new details and characteristics of historical Indian Ocean trade networks.
The oldest known shipwreck in southern Africa was found in Namibia in 2008.1, 2, 3, 4 Forty tons ... more The oldest known shipwreck in southern Africa was found in Namibia in 2008.1, 2, 3, 4 Forty tons of cargo, including gold and silver coins, helped identify the ship as the Bom Jesus, a Portuguese nau (trading vessel) lost in 1533 while headed to India.4, 5, 6 The cargo included >100 elephant tusks,7 which we examined using paleogenomic and stable isotope analyses. Nuclear DNA identified the ivory source as African forest (Loxodonta cyclotis) rather than savanna (Loxodonta africana) elephants. Mitochondrial sequences traced them to West and not Central Africa and from ≥17 herds with distinct haplotypes. Four of the haplotypes are known from modern populations; others were potentially lost to subsequent hunting of elephants for ivory. Stable isotope analyses (δ13C and δ15N) indicated that the elephants were not from deep rainforests but from savanna and mixed habitats. Such habitats surround the Guinean forest block of West Africa8 and accord with the locations of major historic Portuguese trading ports.9,10 West African forest elephants currently range into savanna habitats;11, 12, 13 our findings suggest that this was not consequent to regional decimation of savanna elephants for their ivory in the 19th and 20th centuries. During the time of the Bom Jesus, ivory was a central driver in the formation of maritime trading systems connecting Europe, Africa, and Asia. Our integration of paleogenomic, archeological, and historical methods to analyze the Bom Jesus ivory provides a framework for examining vast collections of archaeological ivories around the world, in shipwrecks and other contexts.
Sex identification of ancient animal biological remains can benefit our understanding of historic... more Sex identification of ancient animal biological remains can benefit our understanding of historical population structure, demography and social behavior. Traditional methods for sex identification (e.g., osteological and morphometric comparisons) may be ineffective when animal remains are not well preserved, when sex distinguishing characteristics have not yet developed, or where organisms do not exhibit sex-associated phenotypic dimorphisms. Here we adapt a method developed for human sex determination so that it can be used to identify the sex of ancient and modern animal taxa. The method identifies sex by calculating the ratio of DNA reads aligning to the X chromosome to DNA reads aligning to autosomes (termed the Rx ratio). We tested the accuracy of this method using low coverage genomes from 15 modern elephants (Loxodonta africana) for which sex was known. We then applied this method to ancient elephant ivory samples for which sex was unknown, and describe how this method can be further adapted to the genomes of other taxa. This method may be especially useful when only low-coverage genomic data are obtainable. Furthermore, because this method relies on only the X and not the Y chromosome, it can be used to determine the sex of organisms for which a reference genome was obtained from a female or for which only the X chromosome is reported. Such taxa include the domestic cat, sheep, goat, and horse; and non-domesticated animals such as the Sumatran orangutan, western lowland gorilla and meerkat. KEYWORDS
This article investigates the nature of usage, as well as the geographical origin, of a small gro... more This article investigates the nature of usage, as well as the geographical origin, of a small group of ivory artifacts recently discovered in the earliest exposed cultural depositions at the Early Islamic (650–1100 C.E.) port of Aylah (Aqaba, Jordan). In addition to explaining the finds and the significance of their context for interpreting possible historical implications, the article uses a range of techniques to learn more about the raw material. In combining archaeological, visual, and biomolecular analyses on these ivories, fresh perspectives are provided that shed new light on the infrastructure and geographical scope of late antique and early medieval trade systems. Moreover, it informs us about the economic and commercial roles played by Red Sea ports in this period and highlights the potential of analyzing organic artifacts from sites in the region to reveal new details and characteristics of historical Indian Ocean trade networks.
Rationale: The oxygen (O) isotope composition of collagen proteins is a potential indicator of ad... more Rationale: The oxygen (O) isotope composition of collagen proteins is a potential indicator of adult residential location, useful for provenancing in ecology, archaeology and forensics. In acidic solution, proteins can exchange O from carboxylic acid moieties with reagent O. This study investigated whether this exchange occurs during demineralisation and gelatinisation preparation of bone/ivory collagen. Methods: EDTA and HCl demineralisation or gelatinisation reagents were made up in waters with different δ 18 O values, and were used to extract collagen from four skeletal tissue samples. Aliquots of extracted collagen were exposed to two different atmospheric waters, at 120°C and ambient temperature, and subsequently dried in a vacuum oven at 40°C or by freeze drying. Sample δ 18 O values were measured by HT‐EA pyrolysis/IRMS using a zero‐blank autosampler. Results: Collagen samples exchanged O with both reagent waters and atmospheric water, which altered sample δ 18 O values. Exchange with reagent waters occurred in all extraction methods, but was greater at lower pH. Damage to the collagen samples during extraction increased O exchange. The nature of exchange of O with atmospheric water depended on the temperature of exposure: kinetic fractionation of O was identified at 120°C but not at ambient temperature. Exchange was difficult to quantify due to the high variability of δ 18 O values between experimental replicates. Conclusions: Studies of δ 18 O values in collagen proteins should avoid extraction methods using acidic solutions.
AbstractRationaleThe oxygen (O) isotope composition of collagen proteins is a potential indicator... more AbstractRationaleThe oxygen (O) isotope composition of collagen proteins is a potential indicator of adult residential location, useful for provenancing in ecology, archaeology and forensics. In acidic solution, proteins can exchange O from carboxylic acid moieties with reagent O. This study investigated whether this exchange occurs during demineralisation and gelatinisation preparation of bone/ivory collagen.MethodsEDTA and HCl demineralisation or gelatinisation reagents were made up in waters with different δ18O values, and were used to extract collagen from four skeletal tissue samples. Aliquots of extracted collagen were exposed to two different atmospheric waters, at 120°C and ambient temperature, and subsequently dried in a vacuum oven at 40°C or by freeze drying. Sample δ18O values were measured by HT-EA pyrolysis/IRMS using a zero-blank autosampler.ResultsCollagen samples exchanged O with both reagent waters and atmospheric water, which altered sample δ18O values. Exchange with reagent waters occurred in all extraction methods, but was greater at lower pH. Damage to the collagen samples during extraction increased O exchange. The nature of exchange of O with atmospheric water depended on the temperature of exposure: kinetic fractionation of O was identified at 120°C but not at ambient temperature. Exchange was difficult to quantify due to the high variability of δ18O values between experimental replicates.ConclusionsStudies of δ18O values in collagen proteins should avoid extraction methods using acidic solutions.
East African elephants have been hunted for their ivory for millennia but the nineteenth century ... more East African elephants have been hunted for their ivory for millennia but the nineteenth century witnessed strongly escalating demand from Europe and North America. It has been suggested that one consequence was that by the 1880s elephant herds along the coast had become scarce, and to meet demand, trade caravans trekked farther into interior regions of East Africa, extending the extraction frontier. The steady decimation of elephant populations coupled with the extension of trade networks have also been claimed to have triggered significant ecological and socio-economic changes that left lasting legacies across the region. To explore the feasibility of using an isotopic approach to uncover a 'moving frontier' of elephant extraction, we constructed a baseline isotope data set (δ 13 C, δ 15 N, δ 18 O and 87 Sr/ 86 Sr) for historic East African elephants known to have come from three distinct regions (coastal, Rift Valley, and inland Lakes). Using the isotope results with other climate data and geographical mapping tools, it was possible to characterise elephants from different habitats across the region. This baseline data set was then used to provenance elephant ivory of unknown geographical provenance that was exported from East Africa during the late nineteenth and early twentieth centuries to determine its likely origin. This produced a better understanding of historic elephant geography in the region, and the data have the potential to be used to provenance older archaeological ivories, and to inform contemporary elephant conservation strategies.
KwaGandaganda, Ndondondwane and Wosi were major Early Farming Community settlements in what is to... more KwaGandaganda, Ndondondwane and Wosi were major Early Farming Community settlements in what is today the KwaZulu-Natal province of South Africa. These sites have yielded, among other remains, abundant evidence of ivory and ivory working dating to the seventh-tenth centuries AD, pre-dating by approximately 200 years the better-known ivory artefacts from sites in the Limpopo River Valley and surrounding regions. We report the results of carbon, nitrogen and strontium isotope analysis to explore the origins and procurement of this ivory, in combination with Zooarchaeology by Mass Spectrometry (ZooMS) to identify the species of animals from which it was derived. All of the ivory studied using ZooMS was elephant, despite the presence of hippopotamus remains on all three sites. Some ivory was probably obtained from elephant herds that lived close to the sites, in the densely wooded river valleys favoured by both elephants and early farmers. Other material came from savannah environments further afield. Ivory found at these three sites was drawn from different catchments, implying a degree of landscape/resource partitioning even at this early stage. These communities clearly invested substantial effort in obtaining ivory from across the region, which speaks to the importance of this commodity in the economy of the time. We suggest that some ivory items were for local use, but that some may have been intended for more distant markets via Indian Ocean trade.
This paper presents the results of the use of a minimally destructive biomolecular technique to e... more This paper presents the results of the use of a minimally destructive biomolecular technique to explore the resource networks behind one of the first specialized urban crafts in early mediaeval northern Europe: the manufacture of composite combs of deer antler. The research incorporates the largest application of species identification by peptide mass fingerprinting (ZooMS) to a mediaeval artefact assemblage: specifically to collections of antler combs, comb manufacturing waste, and raw antler from Ribe, Aarhus, and Aggersborg. It documents the early use of reindeer (Rangifer tarandus) antler, from the 780s ad at the latest, presenting the earliest unambiguous evidence for exchange-links between urban markets in the southern North Sea region and the Scandinavian Peninsula. The results demonstrate that the common conceptual distinction between urban hinterlands and long-distance trade conceals a vital continuity. Long-range networks were vital to urban activities from the first appearance of towns in this part of the world, preceding the historically documented maritime expansion of the Viking Age. We consequently suggest that urbanism is more appropriately defined and researched in terms of network dynamics than as a function of circumscribed catchment areas or hinterlands.
ABSTRACT Walrus-tusk ivory and walrus-hide rope were highly desired goods in Viking Age north-wes... more ABSTRACT Walrus-tusk ivory and walrus-hide rope were highly desired goods in Viking Age north-west Europe. New finds of walrus bone and ivory in early Viking Age contexts in Iceland are concentrated in the south-west, and suggest extensive exploitation of nearby walrus for meat, hide and ivory during the first century of settlement. In Greenland, archaeofauna suggest a very different specialized long-distance hunting of the much larger walrus populations in the Disko Bay area that brought mainly ivory to the settlement areas and eventually to European markets. New lead isotopic analysis of archaeological walrus ivory and bone from Greenland and Iceland offers a tool for identifying possible source regions of walrus ivory during the early Middle Ages. This opens possibilities for assessing the development and relative importance of hunting grounds from the point of view of exported products.
This article investigates the nature of usage, as well as the geographical origin, of a small gro... more This article investigates the nature of usage, as well as the geographical origin, of a small group of ivory artifacts recently discovered in the earliest exposed cultural depositions at the Early Islamic (650–1100 C.E.) port of Aylah (Aqaba, Jordan). In addition to explaining the finds and the significance of their context for interpreting possible historical implications, the article uses a range of techniques to learn more about the raw material. In combining archaeological, visual, and biomolecular analyses on these ivories, fresh perspectives are provided that shed new light on the infrastructure and geographical scope of late antique and early medieval trade systems. Moreover, it informs us about the economic and commercial roles played by Red Sea ports in this period and highlights the potential of analyzing organic artifacts from sites in the region to reveal new details and characteristics of historical Indian Ocean trade networks.
The oldest known shipwreck in southern Africa was found in Namibia in 2008.1, 2, 3, 4 Forty tons ... more The oldest known shipwreck in southern Africa was found in Namibia in 2008.1, 2, 3, 4 Forty tons of cargo, including gold and silver coins, helped identify the ship as the Bom Jesus, a Portuguese nau (trading vessel) lost in 1533 while headed to India.4, 5, 6 The cargo included >100 elephant tusks,7 which we examined using paleogenomic and stable isotope analyses. Nuclear DNA identified the ivory source as African forest (Loxodonta cyclotis) rather than savanna (Loxodonta africana) elephants. Mitochondrial sequences traced them to West and not Central Africa and from ≥17 herds with distinct haplotypes. Four of the haplotypes are known from modern populations; others were potentially lost to subsequent hunting of elephants for ivory. Stable isotope analyses (δ13C and δ15N) indicated that the elephants were not from deep rainforests but from savanna and mixed habitats. Such habitats surround the Guinean forest block of West Africa8 and accord with the locations of major historic Portuguese trading ports.9,10 West African forest elephants currently range into savanna habitats;11, 12, 13 our findings suggest that this was not consequent to regional decimation of savanna elephants for their ivory in the 19th and 20th centuries. During the time of the Bom Jesus, ivory was a central driver in the formation of maritime trading systems connecting Europe, Africa, and Asia. Our integration of paleogenomic, archeological, and historical methods to analyze the Bom Jesus ivory provides a framework for examining vast collections of archaeological ivories around the world, in shipwrecks and other contexts.
Sex identification of ancient animal biological remains can benefit our understanding of historic... more Sex identification of ancient animal biological remains can benefit our understanding of historical population structure, demography and social behavior. Traditional methods for sex identification (e.g., osteological and morphometric comparisons) may be ineffective when animal remains are not well preserved, when sex distinguishing characteristics have not yet developed, or where organisms do not exhibit sex-associated phenotypic dimorphisms. Here we adapt a method developed for human sex determination so that it can be used to identify the sex of ancient and modern animal taxa. The method identifies sex by calculating the ratio of DNA reads aligning to the X chromosome to DNA reads aligning to autosomes (termed the Rx ratio). We tested the accuracy of this method using low coverage genomes from 15 modern elephants (Loxodonta africana) for which sex was known. We then applied this method to ancient elephant ivory samples for which sex was unknown, and describe how this method can be further adapted to the genomes of other taxa. This method may be especially useful when only low-coverage genomic data are obtainable. Furthermore, because this method relies on only the X and not the Y chromosome, it can be used to determine the sex of organisms for which a reference genome was obtained from a female or for which only the X chromosome is reported. Such taxa include the domestic cat, sheep, goat, and horse; and non-domesticated animals such as the Sumatran orangutan, western lowland gorilla and meerkat. KEYWORDS
This article investigates the nature of usage, as well as the geographical origin, of a small gro... more This article investigates the nature of usage, as well as the geographical origin, of a small group of ivory artifacts recently discovered in the earliest exposed cultural depositions at the Early Islamic (650–1100 C.E.) port of Aylah (Aqaba, Jordan). In addition to explaining the finds and the significance of their context for interpreting possible historical implications, the article uses a range of techniques to learn more about the raw material. In combining archaeological, visual, and biomolecular analyses on these ivories, fresh perspectives are provided that shed new light on the infrastructure and geographical scope of late antique and early medieval trade systems. Moreover, it informs us about the economic and commercial roles played by Red Sea ports in this period and highlights the potential of analyzing organic artifacts from sites in the region to reveal new details and characteristics of historical Indian Ocean trade networks.
Rationale: The oxygen (O) isotope composition of collagen proteins is a potential indicator of ad... more Rationale: The oxygen (O) isotope composition of collagen proteins is a potential indicator of adult residential location, useful for provenancing in ecology, archaeology and forensics. In acidic solution, proteins can exchange O from carboxylic acid moieties with reagent O. This study investigated whether this exchange occurs during demineralisation and gelatinisation preparation of bone/ivory collagen. Methods: EDTA and HCl demineralisation or gelatinisation reagents were made up in waters with different δ 18 O values, and were used to extract collagen from four skeletal tissue samples. Aliquots of extracted collagen were exposed to two different atmospheric waters, at 120°C and ambient temperature, and subsequently dried in a vacuum oven at 40°C or by freeze drying. Sample δ 18 O values were measured by HT‐EA pyrolysis/IRMS using a zero‐blank autosampler. Results: Collagen samples exchanged O with both reagent waters and atmospheric water, which altered sample δ 18 O values. Exchange with reagent waters occurred in all extraction methods, but was greater at lower pH. Damage to the collagen samples during extraction increased O exchange. The nature of exchange of O with atmospheric water depended on the temperature of exposure: kinetic fractionation of O was identified at 120°C but not at ambient temperature. Exchange was difficult to quantify due to the high variability of δ 18 O values between experimental replicates. Conclusions: Studies of δ 18 O values in collagen proteins should avoid extraction methods using acidic solutions.
AbstractRationaleThe oxygen (O) isotope composition of collagen proteins is a potential indicator... more AbstractRationaleThe oxygen (O) isotope composition of collagen proteins is a potential indicator of adult residential location, useful for provenancing in ecology, archaeology and forensics. In acidic solution, proteins can exchange O from carboxylic acid moieties with reagent O. This study investigated whether this exchange occurs during demineralisation and gelatinisation preparation of bone/ivory collagen.MethodsEDTA and HCl demineralisation or gelatinisation reagents were made up in waters with different δ18O values, and were used to extract collagen from four skeletal tissue samples. Aliquots of extracted collagen were exposed to two different atmospheric waters, at 120°C and ambient temperature, and subsequently dried in a vacuum oven at 40°C or by freeze drying. Sample δ18O values were measured by HT-EA pyrolysis/IRMS using a zero-blank autosampler.ResultsCollagen samples exchanged O with both reagent waters and atmospheric water, which altered sample δ18O values. Exchange with reagent waters occurred in all extraction methods, but was greater at lower pH. Damage to the collagen samples during extraction increased O exchange. The nature of exchange of O with atmospheric water depended on the temperature of exposure: kinetic fractionation of O was identified at 120°C but not at ambient temperature. Exchange was difficult to quantify due to the high variability of δ18O values between experimental replicates.ConclusionsStudies of δ18O values in collagen proteins should avoid extraction methods using acidic solutions.
East African elephants have been hunted for their ivory for millennia but the nineteenth century ... more East African elephants have been hunted for their ivory for millennia but the nineteenth century witnessed strongly escalating demand from Europe and North America. It has been suggested that one consequence was that by the 1880s elephant herds along the coast had become scarce, and to meet demand, trade caravans trekked farther into interior regions of East Africa, extending the extraction frontier. The steady decimation of elephant populations coupled with the extension of trade networks have also been claimed to have triggered significant ecological and socio-economic changes that left lasting legacies across the region. To explore the feasibility of using an isotopic approach to uncover a 'moving frontier' of elephant extraction, we constructed a baseline isotope data set (δ 13 C, δ 15 N, δ 18 O and 87 Sr/ 86 Sr) for historic East African elephants known to have come from three distinct regions (coastal, Rift Valley, and inland Lakes). Using the isotope results with other climate data and geographical mapping tools, it was possible to characterise elephants from different habitats across the region. This baseline data set was then used to provenance elephant ivory of unknown geographical provenance that was exported from East Africa during the late nineteenth and early twentieth centuries to determine its likely origin. This produced a better understanding of historic elephant geography in the region, and the data have the potential to be used to provenance older archaeological ivories, and to inform contemporary elephant conservation strategies.
KwaGandaganda, Ndondondwane and Wosi were major Early Farming Community settlements in what is to... more KwaGandaganda, Ndondondwane and Wosi were major Early Farming Community settlements in what is today the KwaZulu-Natal province of South Africa. These sites have yielded, among other remains, abundant evidence of ivory and ivory working dating to the seventh-tenth centuries AD, pre-dating by approximately 200 years the better-known ivory artefacts from sites in the Limpopo River Valley and surrounding regions. We report the results of carbon, nitrogen and strontium isotope analysis to explore the origins and procurement of this ivory, in combination with Zooarchaeology by Mass Spectrometry (ZooMS) to identify the species of animals from which it was derived. All of the ivory studied using ZooMS was elephant, despite the presence of hippopotamus remains on all three sites. Some ivory was probably obtained from elephant herds that lived close to the sites, in the densely wooded river valleys favoured by both elephants and early farmers. Other material came from savannah environments further afield. Ivory found at these three sites was drawn from different catchments, implying a degree of landscape/resource partitioning even at this early stage. These communities clearly invested substantial effort in obtaining ivory from across the region, which speaks to the importance of this commodity in the economy of the time. We suggest that some ivory items were for local use, but that some may have been intended for more distant markets via Indian Ocean trade.
This paper presents the results of the use of a minimally destructive biomolecular technique to e... more This paper presents the results of the use of a minimally destructive biomolecular technique to explore the resource networks behind one of the first specialized urban crafts in early mediaeval northern Europe: the manufacture of composite combs of deer antler. The research incorporates the largest application of species identification by peptide mass fingerprinting (ZooMS) to a mediaeval artefact assemblage: specifically to collections of antler combs, comb manufacturing waste, and raw antler from Ribe, Aarhus, and Aggersborg. It documents the early use of reindeer (Rangifer tarandus) antler, from the 780s ad at the latest, presenting the earliest unambiguous evidence for exchange-links between urban markets in the southern North Sea region and the Scandinavian Peninsula. The results demonstrate that the common conceptual distinction between urban hinterlands and long-distance trade conceals a vital continuity. Long-range networks were vital to urban activities from the first appearance of towns in this part of the world, preceding the historically documented maritime expansion of the Viking Age. We consequently suggest that urbanism is more appropriately defined and researched in terms of network dynamics than as a function of circumscribed catchment areas or hinterlands.
ABSTRACT Walrus-tusk ivory and walrus-hide rope were highly desired goods in Viking Age north-wes... more ABSTRACT Walrus-tusk ivory and walrus-hide rope were highly desired goods in Viking Age north-west Europe. New finds of walrus bone and ivory in early Viking Age contexts in Iceland are concentrated in the south-west, and suggest extensive exploitation of nearby walrus for meat, hide and ivory during the first century of settlement. In Greenland, archaeofauna suggest a very different specialized long-distance hunting of the much larger walrus populations in the Disko Bay area that brought mainly ivory to the settlement areas and eventually to European markets. New lead isotopic analysis of archaeological walrus ivory and bone from Greenland and Iceland offers a tool for identifying possible source regions of walrus ivory during the early Middle Ages. This opens possibilities for assessing the development and relative importance of hunting grounds from the point of view of exported products.
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