Periodic Reporting for period 3 - ARCHEIS (Understanding the onset and impact of Aquatic Resource Consumption in Human Evolution using novel Isotopic tracerS)
Reporting period: 2022-03-01 to 2023-08-31
The onset of the systematic consumption of marine resources is thought to mark a turning point for the hominin lineage. To date, this onset cannot be traced, since classic isotope markers are not preserved beyond 50 - 100 ky. Aquatic food products are essential in human nutrition as the main source of polyunsaturated fatty acids in hunter-gatherer diets. The exploitation of marine resources is also thought to have reduced human mobility and enhanced social and technological complexification. Systematic aquatic food consumption could well have been a distinctive feature of Homo sapiens species among his fellow hominins, and has been linked to the astonishing leap in human intelligence and conscience. Yet, this hypothesis is challenged by the existence of mollusk and marine mammal bone remains at Neanderthal archeological sites.
The question of past hominin diets has its role in modern society as its documentation reveals the variability of human diets through times, when we, ourselves, might have to adapt our diets for a more sustainable society. However, the main outcome of this study is a better knowledge of the interaction between human evolution and subsistence strategies.
Recent work demonstrated the sensitivity of Zn isotope composition in bioapatite, the mineral part of bones and teeth, to dietary Zn. By combining classic (C and C/N isotope analyses) and innovative techniques (compound specific C/N and bulk Zn isotope analyses); the ARCHEIS project aims at developing an isotopic tool capable to establish the onset of fish consumption relative to that of shellfish and link the introduction of marine food in hominin diets to their cultural and biological evolution. It will investigate the dependence of d66Zn on trophic level and marine food consumption, by establishing the isotope fractionation mechanisms during intestinal absorption and studying populations consuming aquatic food from different trophic levels: shellfish (low trophic level), fish (intermediate trophic levels) and marine mammals (high trophic levels). The project will also address unsolved questions surrounding the disappearance of pre-Columbian shell mound societies of the Brazilian coast around 2000 BP and the debate on fish consumption of Paleolithic, Mesolithic and Neolithic modern humans.
The question of past hominin diets has its role in modern society as its documentation reveals the variability of human diets through times, when we, ourselves, might have to adapt our diets for a more sustainable society. However, the main outcome of this study is a better knowledge of the interaction between human evolution and subsistence strategies.
Recent work demonstrated the sensitivity of Zn isotope composition in bioapatite, the mineral part of bones and teeth, to dietary Zn. By combining classic (C and C/N isotope analyses) and innovative techniques (compound specific C/N and bulk Zn isotope analyses); the ARCHEIS project aims at developing an isotopic tool capable to establish the onset of fish consumption relative to that of shellfish and link the introduction of marine food in hominin diets to their cultural and biological evolution. It will investigate the dependence of d66Zn on trophic level and marine food consumption, by establishing the isotope fractionation mechanisms during intestinal absorption and studying populations consuming aquatic food from different trophic levels: shellfish (low trophic level), fish (intermediate trophic levels) and marine mammals (high trophic levels). The project will also address unsolved questions surrounding the disappearance of pre-Columbian shell mound societies of the Brazilian coast around 2000 BP and the debate on fish consumption of Paleolithic, Mesolithic and Neolithic modern humans.
WP 1: Calibration of the relationships between aquatic food consumption and bodily Zn stable isotopic compositions.
We finished the analyses for the database, two publications are planned.
After being delayed due to the sanitary crisis, the research expedition has been delayed due to the political situation in Peru
The other hair analyses are currently being planned, we are waiting for all ethical approvals.
Work Package 2: Exploration of Zn isotope signatures in teeth of archeological populations with known aquatic food consumption.
We made a great progress on this part : all analyses have been performed for the WP2.1. Jéssica Mendes Cardoso submitted a paper on the WP2 and is writing her PhD thesis on the subject.
Almost all analyses have been performed for the WP2.2 and should be finished in early 2024. Gwen Le Bras already presented results at the BAP workshop on this part of the project, and wrote a master thesis presenting half of the results.
Work Package 3: Development of quasi-non destructive sampling method for Zn isotope analysis
We are working on this aspect of the project (MicroMill and laser ablation). The MicroMill technique is mastered and part of Jéssica Mendes Cardoso's routine sampling method. The Laser ablation suffered of delay but we are now collaborating with Mathieu Leisen on this part, who already started to work on it when he was post doc in the ARCHEIS project.
Work Package 4: Tracking the rise and fall of aquatic food exploitation in prehistoric times
We finished the isotope analyses of our project tracking aquatic food consumption in the Breton Neolithic. We are actively working on projects involving Paleolithic hominins, and Zineb Moubthaij submitted her first paper on the Taforalt population, which has a pre print online. The preservation of Zn isotopes in tropical Pleistocene food webs for which organic matter was not preserved has been documented and applied to track ancient hominin diets (Bourgon et al., PNAS, 2020; JHE, 2021). The documentation of a Neandertal's diet through Zn isotopes has been published and we sampled another collection in Ardèche.
We finished the analyses for the database, two publications are planned.
After being delayed due to the sanitary crisis, the research expedition has been delayed due to the political situation in Peru
The other hair analyses are currently being planned, we are waiting for all ethical approvals.
Work Package 2: Exploration of Zn isotope signatures in teeth of archeological populations with known aquatic food consumption.
We made a great progress on this part : all analyses have been performed for the WP2.1. Jéssica Mendes Cardoso submitted a paper on the WP2 and is writing her PhD thesis on the subject.
Almost all analyses have been performed for the WP2.2 and should be finished in early 2024. Gwen Le Bras already presented results at the BAP workshop on this part of the project, and wrote a master thesis presenting half of the results.
Work Package 3: Development of quasi-non destructive sampling method for Zn isotope analysis
We are working on this aspect of the project (MicroMill and laser ablation). The MicroMill technique is mastered and part of Jéssica Mendes Cardoso's routine sampling method. The Laser ablation suffered of delay but we are now collaborating with Mathieu Leisen on this part, who already started to work on it when he was post doc in the ARCHEIS project.
Work Package 4: Tracking the rise and fall of aquatic food exploitation in prehistoric times
We finished the isotope analyses of our project tracking aquatic food consumption in the Breton Neolithic. We are actively working on projects involving Paleolithic hominins, and Zineb Moubthaij submitted her first paper on the Taforalt population, which has a pre print online. The preservation of Zn isotopes in tropical Pleistocene food webs for which organic matter was not preserved has been documented and applied to track ancient hominin diets (Bourgon et al., PNAS, 2020; JHE, 2021). The documentation of a Neandertal's diet through Zn isotopes has been published and we sampled another collection in Ardèche.
The ARCHEIS project already documented the possibility to track the age of weaning and diet using Zn isotopes, in the absence of collagen preservation. It already documented the diet of two Pleistocene hominins, a Neandertal and a modern human.
Until the end of the project, we aim at documenting how they can be used to track specific types of seafood consumption using a minimal amount of archeological material
Until the end of the project, we aim at documenting how they can be used to track specific types of seafood consumption using a minimal amount of archeological material