Ellie Nelson, Duston White, Lucy Wheeler, Stefan Meng, Marcin Szymanek, Jaqueline Strahl, Michael Hein, Witold P. Alexandrowicz, Brigitte Urban, Samantha Greeves, Mareike Stahlschmidt, Ralf-Dietrich Kahlke, Tobias Lauer, David Colin Tanner & Kirsty Penkman.
December 2025: Open Research Europe
The eastern North European Plain is an important area for studying Quaternary climate change and archaeology; however, providing chronological constraints for deposits can be challenging. Here, the first aminostratigraphies for the eastern North European Plain are presented, incorporating deposits from at least the last ~1 Ma, which are used to assess the current age attributions to Middle and Late Pleistocene interglacials. These aminostratigraphies are then used to explore expected differences in the extent of IcPD due to differing temperature histories across the study area. Correlations of opercula to regional pollen assemblages representative of the Holsteinian, Eemian and Holocene are used to evaluate the temporal resolution achievable by IcPD within a given interglacial. This work has produced four new aminostratigraphies that can now be used as reference datasets for relative age estimation for the late Middle Pleistocene to the Holocene in the eastern North European Plain.
Ellie Nelson, Dustin White, Lucy Wheeler, Joachim Wedel, Christian Hoselmann, Heiner Heggemann, Wolfgang Rähle & Kirsty Penkman.
October 2025: Journal of Quaternary Sciences
This study presents a new aminostratigraphy for the northern Upper Rhine Graben (Germany). This area is an important archive of Quaternary environmental and climatic changes, but has proven challenging to date. The opercula IcPD has been applied to sedimentary horizons from boreholes collected throughout the area. Using a novel statistical approach to the IcPD analysis, horizons were grouped into clusters of equivalent age. The independent chronological evidence associated with each cluster was used to refine the sediment chronology, providing age constraints for key lithostratigraphic units. This new aminostratigraphy was then used to assess the age of important archaeological deposits within the surrounding area.
Patrick Arnold, Doris Döppes, Federica Alberti , Andreas Füglistaler, Susanne Lindauer, Christian Hoselmann, Ronny Friedrich, Irka Hajdas, Marc R. Dickinson, Frank Menger, Johanna L.A. Paijmans , Love Dalén, Daniel Wegmann , Kirsty Penkham, Axel Barlow, Wilfried Rosendahl and Michael Hofreiter.
September 2025: Current Biology
Late Pleistocene European hippo fossils were long thought to date only to the last interglacial and to have disappeared with the onset of the last glacial, but their origins and extinction timing were uncertain. Genetic analyses show that European hippos were the same species as modern African common hippos, and radiocarbon dating reveals they survived in central Europe well into the middle Weichselian, alongside cold-adapted fauna such as mammoths and woolly rhinos. Low genome-wide diversity indicates these hippos formed a small, isolated population persisting in a temperate refugium in the Upper Rhine Graben during intermittent mild phases of the last glacial.
Laila Patinglag, Marc R. Dickinson, Marcus Hill, Kirsty E.H. Penkman, Kirsty J. Shaw
September 2025: Quaternary Geochronology
This study presents a modular microfluidic system that dramatically reduces sample size and processing time while producing amino acid compositions and D/L values comparable to the standard IcPD method. The approach allows less destructive analysis, works across taxa and operators, and opens the possibility of performing IcPD dating in non-specialist laboratories, including within the fossils’ country of origin.
Jarod Hutson, Feliz Bittmann, Peter Fischer, Alejandro Garcia-Moreno, Sabine Gaudzinski-Windheuser, Ellie Nelson, Jose Ortiz, Kirsty Penkman, Zoran Peric, Daniel Richter, Trinidad Torres, Elaine Turner, Artiza Villaluenga, Dustin White & Olaf Joris.
May 2025: Science Advances
The Schoningen 13II-4 horizon has yielded the most complete Palaeolithic wooden hunting spears ever discovered, pointing towards well-organised hunting parties, where individuals undertook coordinated and specific roles to ensure successful kills of larger and more challenging prey. Previous age estimates had been from underlying sediments, but in this study opercula samples taken from the same horizon as the spears showed that they were likely to date from MIS 7, ~ 200 ka ago.
Debra Colarossi, Geoff Duller, Helen Roberts, Rosie Stirling & Kirsty Penkman.
March 2025: Radiation Measurements
In this paper the TL team tested the impact of daylight exposure on the TL signal from the opercula; the lack of impact of daylight exposure on Peak 3 indicates that opercula-bearing samples can be collected and processed in normal daylight conditions. This is a really important finding as it means that museum specimens are suitable for TL dating, provided an associated sediment sample is available for dose rate calculations. However, as a precaution it is still recommended that light exposure is minimised where possible.
Ellie Nelson, Zoltán Püspöki, Dustin White, György Pogácsás, Richard William McIntosh, Bálint Szappanos, Lucy Wheeler, Tamás Fancsik, and Kirsty Penkman
December 2024, Quaternary Science Reviews
In this study, the first aminostratigraphy for Quaternary deposits within the Pannonian Basin was developed. This is the first time IcPD has been applied to terrestrial deep-core material from a region that is known to have a steep geothermal gradient. In addition, the systematic differences in IcPD due to the competing influences of the age of the sample, burial depth, and integrated temperature is investigated.
Lukas Gegg, Laura Jacob, Olivier Moine, Ellie Nelson, Kirsty E.H. Penkman, Fiona Schwahn, Philipp Stojakowits, Dustin White, Ulrike Wielandt-Schuster and Frank Preusser
December 2024, Quaternary Science Reviews
IcPD analysis of opercula, in combination with other chronostratigraphic approaches, is used to constrain the age of a palustrine layer within a core collected from locality of Eppelheim in the Upper Rhine Graben, Germany. IR-IR luminescence dates support a Holsteinian age, whereas pollen biostratigraphy and IcPD support a Cromerian age. In addition, this record provides a glimpse into the interplay between glacial cycles and tectonic processes.
Gulam Bhat, Nick Ashton, Simon Parfitt, Adviat Jukar, Marc R. Dickinson, Bindra Thusu and Johnathan Craig
October 2024, Quatenary Science Reviews
A study uncovering a remarkable Middle Pleistocene site in Pampore, Kashmir, featuring stone tools alongside remains of at least three Palaeoloxodon elephants. Taxonomic analysis revealed unique features in the elephant skulls, while signs of human intervention included bone flakes but no evidence of butchery. The stone tools, including flakes, cores, and prepared blades, suggest advanced technology for the time. Enamel amino acid dating helps to constrain the ages of the elephant remains to the Middle Pleistocene.
Marc R. Dickinson, Neil Adams, Kate Scott, Adrian Lister and Kirsty Penkman
June 2024, Quaternary Geochronology
Tooth enamel has been used to establish a timeline for Quaternary mammalian fossils from the River Thames valley, focusing on elephants, horses, and bison. Analysis of the amino acid breakdown in over 90 teeth, confirmed that enamel provides a reliable relative dates for deposits from the Middle to Late Pleistocene. This approach directly dates fossils, even from older collections or poorly preserved sites.
Debra Colarossi, Geoff A.T. Duller and Helen M. Roberts
April 2024, Radiation Measurements
To measure the thermoluminescence signal from opercula involves heating them at a uniform rate from room temperature to 400 centigrade. This study explores whether a low temperature peak at ~100 °C that is always seen in calcite when it is irradiated in the laboratory can be used to check whether this heating is reproducible. This study confirms that the peak is useful, but only provided that care is taken to ensure that the timing between irradiation and measurement is uniform.
Kirsty E. H. Penkman, Nigel Thew, Sam Presslee, Sheila Taylor, Ellie Nelson, Daniel Kälin, Marcus Büchi, and Gaudenz Deplazes
February 2024 (preprint), EarthArXiv
An aminostratigraphy has been developed for the Early Pleistocene Höhere and Tiefere Deckschotter, and other Quaternary deposits in the Swiss Plateau. Six different biominerals: Bithynia opercula, shell fragments from Fruticola, Arianta and Cepaea, slug plates and worm granules were used to provide a relative chronology for these deposits. The chronology was validated by existing chronostratigraphic data from the Swiss Plateau, and has provided new insights into a few of the sites.
Geoff A.T. Duller and Helen M. Roberts
February 2024, Radiation Measurements
The thermoluminescence signal from opercula has enormous potential for dating and using an electron multiplying charge coupled device camera makes it possible to look for spatial variation in the signal. However, a critical step in data analysis is to align the 20 to 40 images that are collected of each operculum. In the past this has been done by hand, a time consuming and error prone process. This study describes an automated procedure using ImageJ that is able to rapidly and consistently align images.
Geoff A.T. Duller, Helen M. Roberts and Melissa S. Chapot
August 2023, Radiation Measurements
Irradiating samples using a calibrated radiation source is a vital step in all luminescence dating methods. Detailed analysis of the reproducibility of different luminescence instruments revealed that some were less accurate than others. A rapid method for testing the reproducibility of instruments is described, along with strategies of correcting for this problem. This study improves the reliability and accuracy of luminescence measurements.
Emily Millman, Lucy Wheeler, Katharina Billups, Darrell Kaufman, and Kirsty E. H. Penkman
November 2022, Quaternary Geochronology
This study compares the effects of oxidative pre-treatments on different foraminifera species and evaluates the best approach to improve the reliability of amino acid geochronologies generated from this substrate.
Kirsty E. H. Penkman, Geoff A. T. Duller, Helen M. Roberts, Debra Colarossi, Marc R. Dickinson and Dustin White
October 2022, PNAS
This is a review of the two different dating approaches used by the EQuaTe project. The variety of materials that can be used, time ranges covered and signals which can be analysed are discussed, alongside examples of archaeological applications and their future potential.
Lucy Wheeler, Kirsty E. H. Penkman and Hans Petter Sejrup
February 2021, Quaternary Geochronology
This work provides a method for the isolation of the intra-crystalline proteins within the foraminifera species Neogloboquadrina pachyderm (sinistral). Oxidation of inter-crystalline protein reduced variability of D/L values for younger material. This study also provides material-specific regression equations to successfully convert A/I values from ion exchange chromatography analysis to D/L values for aspartic acid, glutamic acid, and alanine from reverse-phase high-performance liquid chromatography analysis.