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Item Zeitschriftenaufsatz Open Access Complexation of Ln(III) Ions by gluconate : joint investigation applying TRLFS, CE-ICP-MS, NMR, and DF calculations(2025) Zenker, Sophie; Lohmann, Janik; Chiorescu, Ion; Krüger, Sven; Kumke, Michael U.; Reich, Tobias; Schmeide, Katja; Kretzschmar, JeromeThe potential of gluconate, a common cement additive, to mobilize lanthanides (used as analogues of actinides) from cement is investigated. For this purpose, complex formation of trivalent lanthanides, Ln(III), (Ln: La, Sm, Eu, Gd, Lu) with gluconate (GLU) was studied applying time-resolved laser-induced luminescence spectroscopy (TRLFS) in combination with parallel factor analysis (PARAFAC), capillary electrophoresis-inductively coupled plasma mass spectrometry (CE-ICP-MS), nuclear magnetic resonance (NMR) spectroscopy, and density functional (DF) calculations. Up to circumneutral conditions, binary complexes form with Ln(III):GLU stoichiometric ratios of 1:1-1:4 depending only on the Ln:GLU ratio, regardless of the concentration regime (micromolar to millimolar). Coordination facilitates via the carboxyl group (C1) and the adjacent hydroxyl group (at C2) forming a five-membered ring chelation motif, with a probable participation of the C3 hydroxyl group. Beyond circumneutral pH, with the exact onset depending on the specific lanthanide, a fundamental change in speciation takes place. Speciation then becomes more complex upon coexistence and interconversion of several (isomeric) complexes concluded to involve one or more deprotonated GLU hydroxyl groups not necessarily participating in coordination.Item Zeitschriftenaufsatz Open Access Distortion-free sampling of ultrabroadband terahertz electric fields by interfacial spin accumulation(2025) Chekhov, Alexander L.; Behovits, Yannic; Heitz, Julius J. F.; Syskaki, Maria-Andromachi; Jaiswal, Samridh; Gueckstock, Oliver; Serrano, Bruno R.; Ruge, Amon; Kredl, Jana; Wolf, Martin; Münzenberg, Markus; Jakob, Gerhard; Kläui, Mathias; Seifert, Tom S.; Kampfrath, TobiasIn spintronics, FM|HM stacks consisting of a ferromagnetic-metal (FM) and a heavy-metal (HM) layer are model systems for spin transport and spin-charge interconversion. To explore their potential as detectors for ultrabroadband terahertz electromagnetic pulses, we measure the transient optical birefringence the terahertz field induces. Notably, the signal component linear in the FM magnetization agrees excellently with the shape of the incident terahertz electric field at 1 to 13 terahertz and beyond. Analysis indicates that the birefringence arises from the terahertz-field–driven spin accumulation at the FM/HM interface through the spin Rashba-Edelstein effect (SREE). Because of spin-momentum locking, the SREE decays by electron momentum relaxation in <10 femtoseconds, substantially faster than a spin-Hall-effect–induced bulk spin accumulation. Our experiment demonstrates straightforward spintronic sampling of intense ultrabroadband terahertz fields with flat amplitude and phase response. Furthermore, it provides temporal signatures of the SREE and can be viewed as a versatile implementation of interface-specific terahertz time-domain spectroscopy.Item Zeitschriftenaufsatz Open Access Spin Seebeck in the weakly exchange-coupled Van der Waals antiferromagnet across the spin-flip transition(2025) He, Xue; Ding, Shilei; Giil, Hans Gløckner; Wang, Jicheng; Bhukta, Mona; Wu, Mingxing; Shi, Wen; Lin, Zhongchong; Liang, Zhongyu; Yang, Jinbo; Kläui, Mathias; Brataas, Arne; Hou, Yanglong; Wu, RuiSpin Seebeck effect refers to the creation of spin currents due to a temperature gradient in the magnetic materials or across magnet-normal metal interfaces, which can be electrically detected through the inverse spin Hall effect when in contact with heavy metals. It offers fundamental insights into the magnetic properties of materials, including the magnetic phase transition, static magnetic order, and magnon excitations. The behavior of the spin Seebeck effect across the spin-flop transition has been extensively studied, whereas the spin Seebeck effect across the spin-flip transition remains poorly understood. Here, we demonstrate the spin Seebeck effect in a weakly exchange-coupled van der Waals antiferromagnet CrPS4. The spin Seebeck effect increases as the magnetic field increases before the spin-flip transition due to the enhancement of the thermal spin current as a function of the applied field. A peak of spin Seebeck effect is observed at the spin-flip field, which is related to the magnon mode edges across the spin-flip field. Our results extend spin Seebeck effect research to van der Waals antiferromagnets and demonstrate an enhancement of spin Seebeck effect at the spin-flip transition.Item Buchbeitrag Open Access Spiegelungen des American Dream im ›Denkraum Hollywood‹(2020) Wiegmann, EvaItem Zeitschriftenaufsatz Open Access Controllable z-polarized spin current in artificially structured ferromagnetic oxide with strong spin-orbit coupling(2025) Zheng, Dongxing; Xu, Jingkai; Wang, Qingxiao; Liu, Chen; Yang, Tao; Chen, Aitian; Li, Yan; Tang, Meng; Chen, Maolin; Algaidi, Hanin; Jin, Chao; Liu, Kai; Kläui, Mathias; Schwingenschlögl, Udo; Zhang, XixiangRealizing field-free switching of perpendicular magnetization by spin-orbit torques is crucial for developing advanced magnetic memory and logic devices. However, existing methods often involve complex designs or hybrid approaches, which complicates fabrication and affects device stability and scalability. Here, we propose a novel approach using z-polarized spin currents for deterministic switching of perpendicular magnetization through interfacial engineering. We fabricate La0.67Sr0.33MnO3-SrIrO3 (LSIMO) thin films with robust spin-orbit coupling (SOC) and ferromagnetic order through orbital and lattice reconstruction, integrating SrIrO3 and La0.67Sr0.33MnO3 materials. Our investigation reveals that y- and z-polarized spin currents, driven by the spin Hall and spin-orbit precession effects, enable field-free switching of perpendicular magnetization. Notably, the z-polarized spin currents are tunable via the in-plane magnetization of LSIMO. These findings present a promising pathway for the development of energy-efficient spintronic devices, offering improved performance and scalability.Item Zeitschriftenaufsatz Open Access Skeletochronology and isotopic analysis of a captive individual of Alligator mississippiensis Daudin, 1802(2009) Klein, Nicole; Scheyer, Torsten; Tütken, ThomasIn the present study, bone histology and isotope composition (C, N, O) of a femur and three postcranial osteoderms from an approximately 23–25 year-old captive female Alli gator mississippiensis Daudin, 1802 were analyzed to infer the recorded life history. The number of visible annual growth marks in the femur cross-section is less than the known age for the individual concerned, this information clearly shows that skeletochronology has certain limits. However, bone histology reflects very well the traceable life history of this individual and its slow growth in early ontogeny. Bone histology on the basis of the osteoderms shows massive remodeling and an only incompletely preserved growth re cord, reflecting the egg-laying status of this individual. Interestingly, the carbon and espe cially the nitrogen isotope compositions of the osteoderms differ from those of the femur. This presumably reflects dietary changes and/or differences in resorption and remodeling processes during tissue formation of these bones. The N, C, and O isotope composition of the femur is consistent with the food and water the alligator had ingested during the last years of its life. Thus, contrary to the osteoderms, the femur yields reliable data for the reconstruction of an individual’s dietary and environmental history.Item Buchbeitrag Open Access Sorge um die Menschen in der Archäologie – tot, lebendig, ich selbst : Anstoß einer Reflexion(2025) Pahl, JohannaDer Beitrag ist eine Reflexion von Johanna Pahl in der Living Publication "Sorge(n) des Lebens: Herausforderungen der Vergangenheit, Gegenwart und Zukunft aus Sicht der Ancient Studies (Mainz 2022)" hrsg. von Stefan Schreiber und Monika Zöller-Engelhardt. Die Publikation umfasst die Proceedings des gleichnamigen Workshops vom 01.07.2022 an der Johannes Gutenberg-Universität Mainz im Rahmen der Area T1 (Umsorgtes Leben) innerhalb des Profilbereichs "40,000 Years of Human Challenges. Perception, Conceptualization and Coping in Premodern Societies" und wird konstant erweitert. Für die aktuellsten Aufsätze siehe auch https://sorgen-des-lebens.uni-mainz.deItem Zeitschriftenaufsatz Open Access Valley of Whales, Fayum oasis, Egypt : an Eocene window in the evolution of Cetaceans(2023) Helmy, Hassan M.; Tütken, Thomas; Lotfy, HamzaItem Zeitschriftenaufsatz Open Access Tooth enamel nitrogen isotope composition records trophic position : a tool for reconstructing food webs(2023) Leichliter, Jennifer N.; Lüdecke, Tina; Foreman, Alan D.; Bourgon, Nicolas; Duprey, Nicolas N.; Vonhof, Hubert; Souksavatdy, Viengkeo; Bacon, Anne-Marie; Sigman, Daniel M.; Tuüken, Thomas; Martínez-García, AlfredoNitrogen isotopes are widely used to study the trophic position of animals in modern food webs; however, their application in the fossil record is severely limited by degradation of organic material during fossilization. In this study, we show that the nitrogen isotope com position of organic matter preserved in mammalian tooth enamel (δ15Nenamel) records diet and trophic position. The δ15Nenamel of modern African mammals shows a 3.7‰ increase between herbivores and carnivores as expected from trophic enrichment, and there is a strong positive correlation between δ15Nenamel and δ15Nbone-collagen values from the same individuals. Additionally, δ15Nenamel values of Late Pleistocene fossil teeth preserve diet and trophic level information, despite complete diagenetic loss of collagen in the same specimens. We demonstrate that δ15Nenamel represents a powerful geochemical proxy for diet that is applicable to fossils and can help delineate major dietary transitions in ancient vertebrate lineages.Item Zeitschriftenaufsatz Open Access Reply to Ben-Dor and Barkai : a low Zn isotope ratio is not equal to a low Zn content(2023) Jaouen, Klervia; Tütken, Thomas; Bourgon, Nicolas; Lüdecke, Tina; Smith, Geoff M.; Salazar-Garcia, Domingo C.; Hublin, Jean-Jacques; Villalba-Mouco, Vanessa; Méjean, PaulineItem Zeitschriftenaufsatz Open Access Multi-isotope zooarchaeological investigations at Abri du Maras : the paleoecological and paleoenvironmental context of Neanderthal subsistence strategies in the Rhone Valley during MIS 3(2023) Britton, Kate; Jimenez, Elodie-Laure; Le Corre, Mael; Pederzani, Sarah; Daujeard, Camille; Jaouen, Klervia; Vettese, Delphine; Tütken, Thomas; Hublin, Jean-Jacques; Moncel, Marie-HélèneThe exploitation of mid- and large-sized herbivores (ungulates) was central to hominin subsistence across Late Pleistocene Europe. Reconstructing the paleoecology of prey-taxa is key to better understanding procurement strategies, decisions and behaviors, and the isotope analysis of faunal bones and teeth found at archaeological sites represent a powerful means of accessing information about past faunal behaviors. These isotope zooarchaeological approaches also have a near-unique ability to reveal environmental conditions contemporary to the human activities that produced these remains. Here, we present the results of a multi-isotope, multitissue study of ungulate remains from the Middle Paleolithic site of Abri du Maras, southern France, providing new insights into the living landscapes of the Rhône Valley during MIS 3 (level 4.2 = 55 ± 2 to 42 ± 3 ka; level 4.1 = 46 ± 3 to 40 ± 3 ka). Isotope data (carbon, nitrogen) reveal the dietary niches of different ungulate taxa, including the now-extinct giant deer (Megaloceros). Oxygen isotope data are consistent with a mild seasonal climate during level 4.2, where horse (Equus), bison (Bison), and red deer (Cervus elaphus) were exploited year-round. Strontium and sulfur isotope analyses provide new evidence for behavioral plasticity in Late Pleistocene European reindeer (Rangifer) between level 4.2 and level 4.1, indicating a change from the migratory to the sedentary ecotype. In level 4.1, the strong seasonal nature of reindeer exploitation, combined with their nonmigratory behavior, is consistent with a seasonally restricted use of the site by Neanderthals at that time or the preferential hunting of reindeer when in peak physical condition during the autumn.Item Zeitschriftenaufsatz Open Access First application of dental microwear texture analysis to infer theropod feeding ecology(2022) Winkler, Daniela E.; Kubo, Tai; Kubo, Mugino O.; Kaiser, Thomas M.; Tütken, ThomasTheropods were the dominating apex predators in most Jurassic and Cretaceous terrestrial ecosystems. Their feeding ecology has always been of great interest, and new computational methods have yielded more detailed reconstructions of differences in theropod feeding behaviour. Many approaches, however, rely on well-preserved skulls. Dental microwear texture (DMT) analysis is potentially applicable to isolated teeth, and here employed for the first time to investigate dietary ecology of theropods. In particular, we test whether tyrannosaurids show DMT associated with more hard-object feeding than compared to Allosaurus; this would be a sign for higher levels of osteophagy, as has often been suggested. We find no significant difference in complexity and roughness of enamel surfaces between Allosaurus and tyrannosaurids, which conflicts with inferences of more frequent osteophagic behaviour in Tyrannosaurus as compared to other theropods. Orientation of wear features reveals a more pronounced bi-directional puncture-and-pull feeding mode in Allosaurus than in tyrannosaurids. Our results further indicate ontogenetic niche shift in theropods and crocodylians, based on significantly larger height parameters in juvenile theropods which might indicate frequent scavenging, resulting in more bone–tooth contact during feeding. Overall, DMT is found to be very similar between theropods and extant large, broad-snouted crocodylians and shows great similarity in feeding ecology of theropod apex predators throughout the Jurassic and Cretaceous.Item Zeitschriftenaufsatz Open Access A Neandertal dietary conundrum : insights provided by tooth enamel Zn isotopes from Gabasa, Spain(2022) Jaouen, Klervia; Villalba-Mouco, Vanessa; Smith, Geoff M.; Trost, Manuel; Leichliter, Jennifer; Lüdecke, Tina; Méjean, Pauline; Mandrou, Stéphanie; Chmeleff, Jérôme; Guiserix, Danaé; Bourgon, Nicolas; Blasco, Fernanda; Cardoso, Jéssica Mendes; Duquenoy, Camille; Moubtahij, Zineb; Salazar Garcia, Domingo C.; Richards, Michael; Tütken, Thomas; Hublin, Jean-Jacques; Utrilla, Pilar; Montes, LourdesThe characterization of Neandertals’ diets has mostly relied on nitrogen isotope analyses of bone and tooth collagen. However, few nitrogen isotope data have been recovered from bones or teeth from Iberia due to poor collagen preservation at Paleolithic sites in the region. Zinc isotopes have been shown to be a reliable method for reconstructing trophic levels in the absence of organic matter preservation. Here, we present the results of zinc (Zn), strontium (Sr), carbon (C), and oxygen (O) isotope and trace element ratio analysis measured in dental enamel on a Pleistocene food web in Gabasa, Spain, to characterize the diet and ecology of a Middle Paleolithic Neandertal individual. Based on the extremely low δ66Zn value observed in the Neandertal’s tooth enamel, our results support the interpretation of Neandertals as carnivores as already suggested by δ15N isotope values of specimens from other regions. Further work could help identify if such isotopic peculiarities (lowest δ66Zn and highest δ15N of the food web) are due to a metabolic and/or dietary specificity of the Neandertals.Item Zeitschriftenaufsatz Open Access Rapid alteration of cortical bone in fresh- and seawater solutions visualized and quantified from the millimeter down to the atomic scale(2022) Kral, Anna G.; Lagos, Markus; Guagliardo, Paul; Tütken, Thomas; Geisler, ThorstenItem Zeitschriftenaufsatz Open Access Trophic position of Otodus megalodon and great white sharks through time revealed by zinc isotopes(2022) McCormack, Jeremy; Griffiths, Michael L.; Kim, Sora L; Shimada, Kenshu; Karnes, Molly; Maisch, Harry; Pederzani, Sarah; Bourgon, Nicolas; Jaouen, Klervia; Becker, Martin A.; Jöns, Niels; Sisma-Ventura, Guy; Straube, Nicolas; Pollerspöck, Jürgen; Hublin, Jean-Jacques; Eagle, Robert A.; Tütken, ThomasDiet is a crucial trait of an animal’s lifestyle and ecology. The trophic level of an organism indicates its functional position within an ecosystem and holds significance for its ecology and evolution. Here, we demonstrate the use of zinc isotopes (δ66Zn) to geochemically assess the trophic level in diverse extant and extinct sharks, including the Neogene mega tooth shark (Otodus megalodon) and the great white shark (Carcharodon carcharias). We reveal that dietary δ66Zn signatures are preserved in fossil shark tooth enameloid over deep geo logic time and are robust recorders of each species’ trophic level. We observe significant δ66Zn differences among the Otodus and Carcharodon populations implying dietary shifts throughout the Neogene in both genera. Notably, Early Pliocene sympatric C. carcharias and O. megalodon appear to have occupied a similar mean trophic level, a finding that may hold clues to the extinction of the gigantic Neogene megatooth shark.Item Zeitschriftenaufsatz Open Access Combining elemental and immunochemical analyses to characterize diagenetic alteration patterns in ancient skeletal remains(2022) Gatti, L.; Lugli, Federico; Sciutto, Giorgia; Zangheri, M.; Prati, S.; Mirasoli, M.; Silvestrini, S.; Benazzi, S.; Tütken, Thomas; Douka, K.; Collina, C.; Boschin, F.; Romandini, M.; Iacumin, P.; Guardigli, M.; Roda, A.; Mazzeo, R.Bones and teeth are biological archives, but their structure and composition are subjected to alteration overtime due to biological and chemical degradation postmortem, influenced by burial environment and conditions. Nevertheless, organic fraction preservation is mandatory for several archeometric analyses and applications. The mutual protection between biomineral and organic fractions in bones and teeth may lead to a limited diagenetic alteration, promoting a better conservation of the organic fraction. However, the correlation between elemental variations and the presence of organic materials (e.g., collagen) in the same specimen is still unclear. To fill this gap, chemiluminescent (CL) immunochemical imaging analysis has been applied for the first time for collagen localization. Then, Laser Ablation–Inductively Coupled Plasma–Mass Spectrometry (LA–ICP–MS) and CL imaging were combined to investigate the correlation between elemental (i.e., REE, U, Sr, Ba) and collagen distribution. Teeth and bones from various archeological contexts, chronological periods, and characterized by different collagen content were analyzed. Immunochemical analysis revealed a heterogeneous distribution of collagen, especially in highly degraded samples. Subsequently, LA–ICP–MS showed a correlation between the presence of uranium and rare earth elements and areas with low amount of collagen. The innovative integration between the two methods permitted to clarify the mutual relation between elemental variation and collagen preservation overtime, thus contributing to unravel the effects of diagenetic alteration in bones and teeth.Item Zeitschriftenaufsatz Open Access Dental microwear texture analysis correlations in guinea pigs (Cavia porcellus) and sheep (Ovis aries) suggest that dental microwear texture signal consistency is species-specific(2022) Martin, Louise Francoise; Winkler, Daniela Eileen; Ackermans, Nicole Lauren; Müller, Jaqueline; Tütken, Thomas; Kaiser, Thomas; Codron, Daryl; Schulz-Kornas, Ellen; Hatt, Jean-Michel; Clauss, MarcusDental microwear texture (DMT) analysis is used to differentiate abrasive dental wear patterns in many species fed different diets. Because DMT parameters all describe the same surface, they are expected to correlate with each other distinctively. Here, we explore the data range of, and correlations between, DMT parameters to increase the understanding of how this group of proxies records wear within and across species. The analysis was based on subsets of previously published DMT analyses in guinea pigs, sheep, and rabbits fed either a natural whole plant diet (lucerne, grass, bamboo) or pelleted diets with or without added quartz abrasives (guinea pigs and rabbits: up to 45 days, sheep: 17 months). The normalized DMT parameter range (P4: 0.69 ± 0.25; M2: 0.83 ± 0.16) and correlation coefficients (P4: 0.50 ± 0.31; M2: 0.63 ± 0.31) increased along the tooth row in guinea pigs, suggesting that strong correlations may be partially explained by data range. A comparison between sheep and guinea pigs revealed a higher DMT data range in sheep (0.93 ± 0.16; guinea pigs: 0.47 ± 0.29), but this did not translate into more substantial correlation coefficients (sheep: 0.35 ± 0.28; guinea pigs: 0.55 ± 0.32). Adding rabbits to an interspecies comparison of low abrasive dental wear (pelleted lucerne diet), the softer enamel of the hypselodont species showed a smaller data range for DMT parameters (guinea pigs 0.49 ± 0.32, rabbit 0.19 ± 0.18, sheep 0.78 ± 0.22) but again slightly higher correlations coefficients compared to the hypsodont teeth (guinea pigs 0.55 ± 0.31, rabbits 0.56 ± 0.30, sheep 0.42 ± 0.27). The findings suggest that the softer enamel of fast-replaced ever-growing hypselodont cheek teeth shows a greater inherent wear trace consistency, whereas the harder enamel of permanent and non-replaced enamel of hypsodont ruminant teeth records less coherent wear patterns. Because consistent diets were used across taxa, this effect cannot be ascribed to the random overwriting of individual wear traces on the more durable hypsodont teeth. This matches literature reports on reduced DMT pattern consistency on harder materials; possibly, individual wear events become more random in nature on harder material. Given the species-specific differences in enamel characteristics, the findings suggest a certain species-specificity of DMT patterns.Item Zeitschriftenaufsatz Open Access Dental microwear texture gradients in guinea pigs reveal that material properties of the diet affect chewing behaviour(2021) Winkler, Daniela E.; Clauss, Marcus; Rölle, Maximilian; Schulz-Kornas, Ellen; Codron, Daryl; Kaiser, Thomas M.; Tütken, ThomasDental microwear texture analysis (DMTA) is widely used for diet inferences in extant and extinct vertebrates. Often, a reference tooth position is analysed in extant specimens, while isolated teeth are lumped together in fossil datasets. It is therefore important to test whether dental microwear texture (DMT) is tooth position specific and, if so, what causes the differences in wear. Here, we present results from controlled feeding experiments with 72 guinea pigs, which received either fresh or dried natural plant diets of different phytolith content (lucerne, grass, bamboo) or pelleted diets with and without mineral abrasives (frequently encountered by herbivorous mammals in natural habitats). We tested for gradients in dental microwear texture along the upper cheek tooth row. Regardless of abrasive content, guinea pigs on pelleted diets displayed an increase in surface roughness along the tooth row, indicating that posterior tooth positions experience more wear compared with anterior teeth. Guinea pigs feedings on plants of low phytolith content and low abrasiveness (fresh and dry lucerne, fresh grass) showed almost no DMT differences between tooth positions, while individuals feeding on more abrasive plants (dry grass, fresh and dry bamboo) showed a gradient of decreasing surface roughness along the tooth row. We suggest that plant feeding involves continuous intake and comminution by grinding, resulting in posterior tooth positions mainly processing food already partly comminuted and moistened. Pelleted diets require crushing, which exerts higher loads, especially on posterior tooth positions, where bite forces are highest. These differences in chewing behaviour result in opposing wear gradients for plant versus pelleted diets.Item Zeitschriftenaufsatz Open Access Experimental aqueous alteration of cortical bone microarchitecture analyzed by quantitative micro-computed tomography(2021) Kral, Anna G.; Ziegler, Alexander; Tütken, Thomas; Geisler, ThorstenBones are one of the most common vertebrate fossil remains and are widely used as proxy archives in palaeontology and archaeology. Previous histological analyses have shown that bone microarchitecture is mostly well-preserved in fossil remains, but partially or even entirely lost in most archaeological specimens. As a consequence, processes occurring during early diagenesis are pivotal for the preservation of bones and a better understanding of these processes would be required to assess the significance of information stored in fossilized bones. Although much of the changes occur at the nanometer scale, determining the resistance of bone microarchitecture to diagenetic alteration on a microscopic scale constitutes a prerequisite for more detailed studies. Here, results from the first comparative in vitro taphonomy study of cortical bone simulating conditions potentially encountered in early diagenetic settings are presented. In order to accelerate anticipated early diagenetic changes and to facilitate their study in a practical framework, cortical bone samples were exposed to aqueous solutions with temperature, time, and composition of the experimental solutions as controlled parameters. Before and after the experiments, all samples were characterized quantitatively using micro-computed tomography to document structural changes. The results show that the overall change in cortical porosity predominantly occurred in canals with diameters ≤9 µm (∆Ct.Po = ±30%). Furthermore, the data also show that the solution composition had a stronger impact on changes observed than either temperature or time. It was also found that samples from the two experimental series with a freshwater-like solution composition showed a characteristic reaction rim. However, it remains unclear at present if the observed changes have an impact on reactions occurring at the nanometer scale. Nonetheless, the results clearly demonstrate that on a micrometer scale down to 3 μm, bone microarchitecture is largely resistant to aqueous alteration, even under very different physicochemical conditions. In addition, the data illustrate the complexity of the interaction of different diagenetic factors. The results presented here provide a solid framework for future investigations on reaction and transport mechanisms occurring during the early diagenesis of fossil bones.Item Zeitschriftenaufsatz Open Access Zinc isotopes in Late Pleistocene fossil teeth from a Southeast Asian cave setting preserve paleodietary information(2020) Bourgon, Nicolas; Jaouen, Klervia; Bacon, Anne-Marie; Jochum, Klaus Peter; Dufour, Elise; Duringer, Philippe; Ponche, Jean-Luc; Joannes-Boyau, Renaud; Boesch, Quentin; Antoine, Pierre-Olivier; Hullot, Manon; Weis, Ulrike; Schulz-Kornas, Ellen; Trost, Manuel; Fiorillo, Denis; Demeter, Fabrice; Patole-Edoumba, Elise; Shackelford, Laura L; Dunn, Tyler E.; Zachwieja, Alexandra; Duangthongchit, Somoh; Sayavonkhamdy, Thongsa; Sichanthongtip, Phonephanh; Sihanam, Daovee; Souksavatdy, Viengkeo; Hublin, Jean-Jacques; Tütken, ThomasStable carbon and nitrogen isotope ratios of collagen from bone and dentin have frequently been used for dietary reconstruction, but this method is limited by protein preservation. Isotopes of the trace element zinc (Zn) in bioapatite constitute a promising proxy to infer dietary information from extant and extinct vertebrates. The 66Zn/64Zn ratio (expressed as δ66Zn value) shows an enrichment of the heavy isotope in mammals along each trophic step. However, preservation of diet-related δ66Zn values in fossil teeth has not been assessed yet. Here, we analyzed enamel of fossil teeth from the Late Pleistocene (38.4–13.5 ka) mammalian assemblage of the Tam Hay Marklot (THM) cave in northeastern Laos, to reconstruct the food web and assess the preservation of original δ66Zn values. Distinct enamel δ66Zn values of the fossil taxa (δ66Zncarnivore < δ66Znomnivore < δ66Znherbivore) according to their expected feeding habits were observed, with a trophic carnivore-herbivore spacing of +0.60‰ and omnivores having intermediate values. Zn and trace element concentration profiles similar to those of modern teeth also indicate minimal impact of diagenesis on the enamel. While further work is needed to explore preservation for settings with different taphonomic conditions, the diet-related δ66Zn values in fossil enamel from THM cave suggest an excellent long-term preservation potential, even under tropical conditions that are well known to be adverse for collagen preservation. Zinc isotopes could thus provide a new tool to assess the diet of fossil hominins and associated fauna, as well as trophic relationships in past food webs.