We report a new relative sea level curve from Inglefield Land, northwest Greenland, to investigate the transition from maximum to minimum loading across Nares Strait. We sampled marine bivalves and terrestrial macrofossils for radiocarbon dating from raised marine terraces in Rensselaer Valley, Inglefield Land (78.58°N, 70.71°W) to constrain relative sea level through the Holocene. The oldest terrestrial macrofossil of 9010–8650 cal yr BP provides a minimum-limiting constraint for the deglaciation. Sea level fell rapidly from the marine limit at 85 ± 4 m to 37.5 ± 4 m above sea level (m asl) between 9010–8650 and 7970–7790 cal yr BP at a rate of 49 m/ka. The rate of sea -level fall decreased to 11 m/ka between 7970–7790 and 5320–5060 cal yr BP, when it fell from 37.5 ± 4 to 9 ± 4 m asl. After 5,320–5,060 cal yr BP, we estimate sea level fell at a lower rate of 2 m/ka to modern sea level. The period of fastest emergence in Inglefield Land is earlier in time than in Hall Land, reflecting earlier deglaciation, and is steeper than in Hall Land and Washington Land. This sea-level history captures the transition from the style of emergence from Pituffik to Hall Land.

We investigated radiocarbon dates of human bone samples from several medieval sites in Trondheim, central Norway. Stable isotope data was used to estimate marine correction for the radiocarbon dates, which is necessary to correct the radiocarbon ages and establish age models for the archaeological layers. We observed that a marine correction without ΔR does not lead to a well-defined model for all sites. Allowing a variable ΔR improves the model, which indicates that food sources and trade routes have changed over time, influencing the mobility of food resources as well as of people. However, this does not work for all sites, indicating that variation of reservoir ages could also be the result of individual preferences for the food and that fish with different ΔR, and thus different geographical origin, was consumed during the same periods. Many radiocarbon and stable isotope (δ13C, δ15N) measurements have been carried out for the project. We calculated %marine consumption from the isotope values and found that it varies greatly, between 7% and 51%, and apparently independent of period, social status, churchyard location or other factors. Based on these data, we determined average reservoir ages for the marine food consumed in Trondheim during different phases, varying between ΔR = –150 and 280 years.

Radiocarbon (14C) dating is a powerful tool for establishing reliable chronologies for proxy records recovered from environmental archives, including lacustrine sediments. However, lacustrine sediments are often limited with respect to availability of material such as terrestrial macrofossils that are traditionally targeted for 14C dating. Flow cytometry, in combination with physicochemical preprocessing, is an emerging technique for the isolation of pollen from terrestrial sediments, holding the promise of pollen recovery of sufficient purity and efficiency for routine 14C analysis. Here, we examine the performance of this approach by undertaking a comprehensive blank assessment for a new pollen isolation protocol and comparing pollen-14C data against established chronologies for two lake records. Our procedure yields consistent values for constant contamination with extraneous carbon of 1.34±0.40 µg C and an F14C of 0.85±0.04, rendering our method suitable for microscale 14C analysis. The pollen-14C data are largely in agreement with age estimates for the same layers of the lake sediment cores based on macrofossil-14C analysis and tephrochronology. However, we also observe that our pollen samples appear to be, on average, slightly older than their macrofossil counterparts. We hypothesize this to be the result of sedimentary and translocation processes that retard pollen transport and lacustrine deposition.

We report new AMS radiocarbon dates of 16 samples from the Holocene deposits of the Vistula Spit, a large coastal barrier landform on the Southern Baltic coast. Collection of the samples was conducted directly from the sedimentary succession excavated during 2020–2022 construction of the Vistula Spit shipping canal. The dated material represents several paleosol horizons and peat lenses buried in the dune deposits, as well as their substrate – beach and shallow marine deposits.

A range of sizes of eight sea urchin species in the Family Echinometridae (Echinostrephus aciculatus, Heliocidaris erythrogramma, Colobocentrotus atratus, Heterocentrotus mamillatus, Heterocentrotus trigonarius, Echinometra mathaei, Echinometra lucunter, and Echinometra vanbrunti) were digitized and their shapes decomposed using elliptical Fourier analysis to quantify shape differences. Coefficients of sines and cosines of harmonics were used in a principal components analysis to show the separation of species. The principal component analysis shows the Echinometridae shape morphospace with the greatest separation of Echinostrephus and Colobocentrotus from other species. Major loadings were related to morphological measurements: height/diameter, lift of the oral surface above the substrate, and position of the ambitus to height. All species showed an increase in height/diameter with size, but only some species showed a correlation of oral lift or position of the ambitus with Fourier coefficients.

The bulk organic-matter content of near-surface sediment is widely used for radiocarbon (14C) dating, despite often containing organic carbon (OC) older than the depositional age. Low-temperature combustion can mitigate the influence of old OC, producing ages closer to the depositional age. We developed a simple method to determine the 14C age of the low-temperature (<250°C) component of bulk sediment. Sediment samples from five Arctic lakes were heated up to 400°C, revealing that at 250°C, about half of the OC combusts, leaving behind the more recalcitrant fraction. We applied this method to 64 samples from late glacial and Holocene sediment cores, analyzing 14C and % OC in two aliquots: one heated at 250°C and one unheated. The low-temperature 14C age was calculated by difference using a two-component mixing model. Accuracy was assessed by comparing ages with macrofossils from 48 samples, and reproducibility was tested using a standard reference material. Results show that low-temperature combustion yields 14C ages with an interquartile range of 115 years, and with reproducibility on par with that of macrofossil dating. On average, the ages differ by 932 years from macrofossils, compared to a 2425-year difference for conventional bulk-sediment ages analyzed in this study. Accuracy improves for samples where the proportion of residual OC after heating is low. This practical and efficient method complements macrofossil dating, supports analysis of a large number of samples, and provides insights into sedimentary carbon cycling.

The mudskipper Boleophthalmus dussumieri (Teleostei, Gobiiformes, Oxudercidae) is an amphibious goby native to the Indian Ocean, from Kuwait Bay and Persian Gulf to the northeast of the Arabian Sea and the western coast of India. This study reports on the first record of B. dussumieri in the Atlantic Ocean, based on morphological and molecular evidence. A single specimen was collected in September 2024 in São Marcos Bay, on the coast of the state of Maranhão (Brazilian Amazon Coast). This is the second exotic species of oxudercid goby reported for the coast of Maranhão, possibly accidentally introduced through ballast water discharge.

The use of ultrafiltration remains a subject of ongoing debate among pretreatment methods employed in radiocarbon dating of mammalian archaeological bone. However, such discourse had not previously extended to the archaeology of the Canary Islands (Spain), where detailed descriptions of laboratory processing methods for collagen purification often remain absent. Our study presents a case study involving a new set of radiocarbon dates obtained from the remains of ancient natives of Tenerife Island. For the first time in this region, we compared the results of ultrafiltered with non-ultrafiltered collagen from the same individuals, focusing on the method’s implications for dating accuracy in the Canaries. Through an examination of the cleaning protocols of ultrafilters and an assessment of the reliability of radiocarbon dating outcomes, we have found that ultrafiltration may influence the accuracy of results. However, given the additional handling required and the potential risk of contaminating the samples, its application should be carefully considered. In the context of the Canary Islands, ultrafiltration may be most relevant for samples associated with early human occupation, though further research is needed to assess its necessity across different biogeographical contexts. This communication further contributes to a broader understanding of preparation methods for radiocarbon dating bone from various environmental contexts, emphasizing the uniqueness of each case. Furthermore, we discuss the implications of our findings for archaeological research in the Canary Islands, highlighting the methodological gaps that persist in the region and underscoring the importance of ensuring the accuracy and reliability of chronological interpretations in archaeological investigations.

The present study aimed to elucidate the extent of microplastic (MP) contamination in the Guandu River basin. Samples were collected from surface waters using a Manta trawl at 11 sites in two seasonal periods. MPs abundance was 6.1 ± 4.9 particles m−3 in the cold-dry season, and 2.3 ± 1.1 particles m−3 in the warm-rainy season. Four shapes and 12 colors were identified, indicating a high degree of particle diversity. Fragments were the most common, followed by fibers. The frequent colors were black, blue and transparent. Eleven plastic polymers were identified using micro-Fourier transform infrared spectroscopy analysis; the dominant ones were polyethylene and polypropylene. Artificial cellulose particles (including the semisynthetic polymer rayon) were also detected in high relative abundance. No significant difference in MP abundance was found between seasons and limnic conditions. There was a significant trend toward higher abundance of MPs near areas with greater urban influence and lower abundance in reservoirs surrounded by less urbanized areas (upstream river). Therefore, MPs appeared to be influenced by land use and occupation, with higher abundance in more urbanized areas, suggesting an urban–rural effect.

Using calibrated radiocarbon dates, this study investigates climate signals recorded in fluvial sedimentary archives from southern Poland, eastern Netherlands, and eastern Germany. Summed probability density functions (PDFs) were constructed and analyzed in the context of INTIMATE stratigraphy. The results indicate that fluvial sedimentation and erosion processes were closely linked to climate fluctuations, particularly during GS/GI and GI/GS transitions. The analyses indicate multi-scale relationships between regional geomorphological processes and global climate trends during the period from 50 to 15 cal kBP. This study provides a reconstruction of Late Pleistocene fluvial activity and highlights the need for more precise radiocarbon dates to refine correlations between regional and global climate events.

Scientists still debate whether small groups of Paleolithic hunter-gatherers caused the extinction of large Ice Age animals like prehistoric elephants, giant sloths and cave lions. Beyond paleontology, this question has deep sociological implications and is relevant for how we understand the role of humankind in today’s environmental crisis. A human-driven megafauna extinction has often fostered the idea of a naturalization of human environmental impacts and the belief that all people (modern or ancient, rich or poor, from any part of the world) share responsibility for the current crisis. But is that true? In the review, I discuss whether a long evolutionary history of impacts really makes us inevitably destructive, compelling humanity to accept a devastating anthropocentric dominance as the fateful destiny natural selection built for us. In contrast, I argue that, while our exceptional ability to shape environments has made us a ‘hyper-keystone’ species, benefiting only a few species and humans, this same ability also has the potential to help us restore balance to the world. That requires rejecting anthropocentric supremacy and placing ecosystems at the center stage of our relationship with nonhuman nature. We may have wiped out the mammoths and mastodons, but human destructiveness is not fate.

The Ordovician Puna retroarc foreland basin in northwestern Argentina accommodated the c. 3500 m thick Puna Turbidite Complex, consisting of the Lower and Upper Turbidite systems. The turbidites accumulated in the Middle Ordovician over 15 Myr. 744 new detrital zircon U-Pb ages obtained from seven medium and fine-sand turbidite layers of the Puna Turbidite Complex reflect a South American provenance from the Terra Amazonica and the early Terra Australis orogens between 2000 Ma and 440 Ma. The most abundant detrital zircon age group consists of Ordovician ages representing the Famatinian orogenic cycle (520–410 Ma), followed by those of the preceding Olmos-Pampean orogenic cycle (650–520 Ma), the Neoproterozoic rifting phase connected to Rodinia dispersal (1000–650 Ma) and the Sunsás orogenic cycle (1200–1000 Ma). The age distributions of fine and medium sand turbidite layers are statistically almost identical and do not display significant effects of sorting. Subchondritic ϵHf(t) values of Ordovician zircon emphasise crustal recycling and reworking as the most significant processes during the Famatinian Orogenic cycle. Hf(TDM2) indicates that crustal material mostly formed as juvenile crust in Mesoproterozoic time, during the Rȏndonia-San Ignacio and Sunsás orogenic cycles. Detrital zircon δ18O data obtained from syndepositional Ordovician zircon are elevated and range between 6.5 and 8.8 ‰. Combined with similar data from the literature on intrusive and orthometamorphic rocks of the Famatinian magmatic arc, these data indicate that crustal recycling and reworking of supracrustal rocks played a major role in the evolution of the Famatinian arc in the southern central Andes.

Mars, one of the most Earth-like celestial bodies in the Solar System, is a key focus in the search for extraterrestrial life. However, pure liquid water – essential for life as we know it – is unstable on its surface today due to low pressure and frigid conditions. Concentrated salt solutions (brines) may form through the deliquescence of hygroscopic salts like chlorates and perchlorates detected on Mars, offering a potential water source for hypothetical halotolerant organisms due to the brines’ lower freezing point and reduced vapour pressure. This study simulates brine formation on Mars using a methodical setup. Martian global regolith simulant MGS-1 was either supplemented with hygroscopic salts such as sodium chloride (NaCl), sodium chlorate (NaClO3), sodium perchlorate (NaClO4) or used without the addition of salts as a control. Samples were inoculated with the halotolerant yeast Debaryomyces hansenii, chosen for its high (per)chlorate tolerance. Desiccated samples were transferred to an environment with constant relative humidity (98%), allowing the salts to absorb water from the atmosphere through deliquescence. The study examined the survival of D. hansenii after desiccation and its ability to grow using water absorbed through deliquescence. The results revealed that D. hansenii survived the desiccation in samples containing NaClO3, NaCl or no additional salt and grew in the control samples as well as in the deliquescent-driven NaClO3 and NaCl brines. No survival was observed in samples containing NaClO4 after the desiccation step. These findings suggest that Mars could potentially harbour life in specific niches where deliquescent brines form, specifically in NaCl or NaClO3 rich areas. NaClO4, at least for the yeast tested in this study, is too toxic to support survival or growth in deliquescene-driven habitats.