Quaternary

For many years, the temporal distribution of pigs in the Pleistocene of Europe drew little attention. This changed when, what became known as, the “suid gap” hypo-thesis was published. Subsequent publications added elements to this hypothesis, while others questioned the hypothesis and even the existence of a “suid gap”. In its most complete form the hypothesis consists of a chain of arguments: (1) pigs are r-selected (a life history trait), (2) therefore fossils of their deciduous teeth are particularly abundant, (3) because being r-selected, pigs are abundant, (4) sites without pig fossils are sure indicators of their absence, (5) at 1.8 Ma, humans dispersed into Europe driving Sus strozzii to extinction in all the continent by competitive displacement, but not in the Middle East, (6) around 1.2 Ma pigs appeared again in Europe, either Sus strozzii, coming from the Middle East, or another species. The proposed link between human and pig ecology increased the interest of this hypothesis. Recently parts of this hypothesis were questioned and a polemic arose. It is the aim of this paper to review the literature and arguments used in favour and against this “suid gap” hypothesis. The hypothesis is rejected, but the life history traits of pigs may prove to be of interest for comparison with humans. Full article

Loess–palaeosol sequences (LPSs) are continuous records of palaeoenvironmental and palaeoclimatic conditions during the Quaternary. This study includes 17 LPS located in the NE of the Iberian Peninsula, irregularly distributed, associated with different river basins: the Ebro Basin, the Mora Basin, and the Ter sub-basin. The soils developed on these loess deposits present a loam–sandy texture, coarser than the typical loess, ochre in colour, with variable thickness (1–12 m), calcareous composition (20–45% CaCO₃ eq.), very low or null organic matter (OM), and basic pH. These deposits have been classified as desert LPS, whose pedogenesis is mainly associated with the redistribution of calcium carbonate and, in some cases, gypsum. Several methodologies have been applied to determine their mineralogical, physical, and chemical characteristics and date them by luminescence techniques. In addition, some relevant pedofeatures (porosity, CaCO₃, gypsum, etc.) have been characterised in detail. The aims of the present study have been to know the pedogenic development of the LPS by defining the main soil-forming factors that have affected them in order to associate these factors with the characteristic palaeoclimatic and palaeoenvironmental conditions reported in this area over time and to improve the understanding of soil evolution. Full article

The architectural artefacts, materials, and techniques used for constructing shelters may share some common properties derived from the architectural culture that has evolved within the human species. This article examines the material features and settlement organisations employed in the nest-building activities of early human species and the shelter forms of indigenous peoples residing in sub-Saharan Africa. It questions whether early modern human notions of architectural heritage, which lack substantiation, might have influenced nest construction, typological differentiation, material utilisation, and the transmission of practices to subsequent generations and habitats. The focus is on home-based spatial organisation and the construction of structures. We recognise the need to clarify some fundamental misunderstandings regarding the nature of cultural and archaeological taxonomies, as well as the misuse of analogical reasoning when comparing contemporary hunter–gatherer populations with certain hominin groups. The paper aims to explore whether the early ‘Homo architecture’ in Africa bears any resemblance to that of modern Africans. The central inquiry of this study is whether indigenous architectural artefacts, materials, and techniques have been passed down throughout the evolution of architectural culture. The discussion suggests that the architectural products found in the settlement remains of early Homo species may exhibit characteristics similar to the huts of the indigenous people, who live as hunter–gatherers in sub-Saharan Africa. Discussing the architectural activities of different human species proves fruitful, as early architectural understanding and principles can be adapted to contemporary placemaking scenarios, urban design approaches, and housing models. We believe that, with further evidence, this foundational idea has the potential to be developed further. Full article

Fossilized body parts of two cold-adapted ground beetle species, Elaphrus lapponicus and Diacheila polita, were identified from a deposit dated to the Late Glacial period in Hokkaido, Japan. The paleoenvironmental reconstruction presented here has been based on modern temperature ranges and environmental conditions, along with paleobotanical evidence from the site. Late Glacial temperatures were at least 6 degrees °C lower than modern temperatures in summer, and the area around the site was mostly covered with forest tundra, which exists only in areas further north than Hokkaido. Full article

Preserved macro-botanical and charcoal remains collected from the Zhumucun site have revealed the paleodiet and agricultural production of a small settlement during the Liangzhu period. Further, they have also helped to reconstruct the landscape and social organization that occurred therein. The plant remains assemblage shows that rice was the main crop at this site; however, the appearance of the millets may also indicate the spread and communication between southern and northern China. An analysis of the discarded spikelets confirmed that rice was locally produced and processed. A study of charcoal helped restore the vegetation landscape in the settlement and provided valuable insights for reconstructing the functional zoning and agricultural production at the site. Following an analysis of the plant distribution and utilization patterns at the site, it became clear that the Zhumucun site functioned as a small agricultural settlement. Compared to other settlements from the Liangzhu period, the Zhumucun site likely supported a smaller population. The site could be divided into smaller groups, including facilities in residential areas, processing areas, tomb areas, and farming areas. Agricultural production at the Zhumucun site appears to have been highly coordinated, with activities carried out in a unified manner and primarily by local households. This efficient system of resource management likely reflects a well-organized labor structure, where food surpluses may have been redistributed to support other higher-level settlements. Full article

Anemone altaica Fisch. ex C. A. Mey., a component of the tertiary boreo-nemoral vegetation complex, exhibits a disjunct distribution from European Russia to Central China. The Khamar-Daban Ridge, extending along Lake Baikal’s southern coast, has served as a refugium preserving mesophilic forest remnants in South Siberia since the Pleistocene. This study aimed to elucidate the phylogenetic relationships and historical biogeography of A. altaica within the Khamar-Daban refugium using plastid DNA markers (trnL + trnL-trnF). Phylogenetic and mismatch distribution analysis revealed polyphyly (more specifically diphyly) among A. altaica lineages, suggesting past hybridization events with related species followed by backcrossing. Estimation of isolation by distance effect, spatial autocorrelation analysis, PCoA, and AMOVA indicated a clear spatial genetic structure for A. altaica on the Khamar-Daban Ridge. The most reliable geographical model suggests that during periods of Pleistocene cooling, A. altaica persisted in at least six microrefugia within the ridge. Populations associated with these microrefugia formed western, central, and eastern genetic supergroups with limited gene flow among them. Gene flow likely occurred more easily during glaciations or early interglacials when the subalpine zone shifted closer to Lake Baikal due to the depression of the snow boundary, allowing adjacent populations to intermingle along the glacial edges and terminal moraines in mountain forest belt. Full article

Dental wear analyses of extinct animals offer key insights into their dietary preferences and in turn contribute substantially to palaeoenvironmental reconstructions, leading to more accurate interpretations about past ecosystems. This study employs dental mesowear analysis on Pliocene and Pleistocene elephants and mammoths from several localities in Northern Greece (Ptolemais Basin, Mygdonia Basin, Drama Basin, and the Neapolis-Grevena Basin), aiming to classify them into three main dietary categories (browsers, mixed-feeders, grazers) and investigate potential niche partitioning. The method relies on documenting the wear pattern of molar surfaces through angle measurements on the enamel ridges, which reflect the average annual diet of the examined taxon and in turn the annual ecological conditions of the studied area. Prior to the palaeodietary study and in order to ensure the taxonomic attribution of the examined specimens, a taxonomic review was conducted which confirmed the presence of the mammoths Mammuthus rumanus, Mammuthus meridionalis (southern mammoth), and Mammuthus trogontherii (steppe mammoth), and the European straight-tusked elephant Palaeoloxodon antiquus. Dental mesowear results indicate a grazing diet for M. (cf.) rumanus, a mainly browsing diet for M. meridionalis but mixed-feeding to grazing for the subspecies Mammuthus meridionalis vestinus, a grazing one for M. trogontherii, and a wide diet spectrum for P. antiquus, including browsing, mixed-feeding and grazing, depending on the locality. This study expands our knowledge on the palaeoecology of Greek proboscideans and further highlights the importance of mesowear analysis on proboscidean teeth for palaeodietary and palaeoenviromental inferences. Full article

A comprehensive database of paleo vegetation from Kundala Lake, Kerala, was used for a palynological study in a 120 cm sedimentary profile from Kundala Lake (1700 mamsl), Palni Hills, to understand the climate and vegetation equilibrium during the last four millennia. On the basis of pollen assemblage and cluster analysis, a relatively high percentage of evergreen vegetation between 4.3 and 3.4 ka (phase I) was inferred to represent the relicts of middle Holocene vegetation during a warmer climate. Subsequently, in the periods of 3.4–2.3 ka (phase II) and 2.3–0.87 ka (phase III), herbs/shrubs dominated. A relative increase in the percentage of arboreals along with herbaceous taxa was again observed from 0.87 to 0.12 ka (phase IV). Later, in phase V (from 1820 AD to present), few new plant taxa were recorded. On the basis of the ‘coexistence approach’, the Mean Annual Temperature (MAT) was inferred to be 22 °C, 15 °C, 15 °C, 20 °C and 22 °C during phases I to V, respectively. The Mean Annual Precipitation (MAP)was 2660 ± 3700 mm from ~4.3 to 0.12 ka; however, it decreased to ~1750 mm between 3.4 and 2.3 ka. However, pollen evidence reveals short-term cooler spells during the 16/17th century AD, which is in concordance with the globally recorded cooler and arid climate that began sometime from ~5.0 to 4.0 ka. A thematic digital elevation map of vegetation reconstructed for the years 2005 and 2018 shows a reduction in evergreen plants and water bodies in the vicinity of Kundala Lake, which was correlated with the results of palynological studies and Indian meteorological data for the last ~100 years in the region. Full article

The timing, cause, and magnitude of mammalian extinctions during the African Middle Pleistocene remain largely unresolved. The demise of Elephas/Palaeoloxodon recki, a lineage that had a great geographic and temporal span, represents a particularly enigmatic case of megafaunal extinction. Previous studies of Early Pleistocene fossil material have proposed that this lineage was a strict C₄-grazer, with its dietary specialization causing its extinction during a period of climatic instability that coincided with the Late Acheulean. Others have associated its disappearance with overhunting by hominins during the same period. We contribute to this debate by analyzing carbon and oxygen isotope data from the tooth enamel of late Early and Middle Pleistocene Palaeoloxodon specimens from various localities in the Afar Rift. To contextualize the isotopic data of Palaeoloxodon within its broader ecosystem, we also provide data from non-elephant species. Carbon isotope values indicate that while C₄ plants dominated diets, varying amounts of C₃ vegetation were also consumed throughout this period. Oxygen isotope values reflect an initial focus on stable water sources that were later broadened to include transient sources. Serially sampled teeth of P. cf. recki recki from Late Acheulean contexts in the Megenta research area show no significant seasonal shifts in δ¹³C or δ¹⁸O values, even during a period of heightened climatic instability regionally. Taken together, our results suggest that Palaeoloxodon was capable of flexibility in diet and drinking habits which belies its morphological specializations. Our results do not support the idea that an inability to adapt to climatic instability caused the extinction of P. recki recki during the Late Acheulean. There is also currently no solid evidence that hominin hunting activities were the cause. However, we cannot discount the potential cumulative impact of climatic-induced environmental pressures and advancements in hominin hunting technologies during the early Middle Stone Age on the eventual extinction of the Palaeoloxodon lineage during the Middle–Late Pleistocene interface. Full article

The Yucatán Peninsula, a key region of the ancient Maya civilization, has long presented challenges in establishing absolute chronological frameworks for its cultural practices. While the central regions of Mesoamerica have been extensively studied, the southern areas, including the Yucatán, remain underexplored. Limekilns, integral to lime production in pre-Hispanic Maya society, are well suited for archaeomagnetic studies due to the high temperatures (>700 °C) required for their operation. This study analyzed 108 specimens from 12 limekilns near Mérida, Yucatán, using rock-magnetic experiments and progressive alternating field demagnetization to refine the absolute chronology and determine the continuity of the lime production technology. Thermoremanent magnetization was predominantly carried by magnetite-like phases. Archaeomagnetic directions were successfully obtained for ten kilns with robust precision parameters. Age intervals were calculated using global geomagnetic models (SHA.DIF.14K, SHAWQ.2K), local paleosecular variation curves, and a Bootstrap resampling method. The analysis identified apparently two distinct chronological clusters: one between 900 and 1000 AD, associated with the Late–Terminal Classic period, and another near 1500 AD, just prior to the Spanish conquest. These findings reveal an apparent 500-year hiatus in lime production, followed by the potential reuse of kilns. Our study refines the chronological framework for Mayan lime production and its cultural and technological evolution. The integration of archaeomagnetic methods demonstrates their far-reaching applicability in addressing questions of continuity, reuse, and technological adaptation, contributing to broader debates on ancient pyrotechnological practices and their socioeconomic implications. Full article

As humans expanded across the globe, the Americas were the last continents to be colonized. While debates persist regarding the timing and mechanisms of this process, it is widely accepted that by the Pleistocene–Holocene transition, the New World was populated from Alaska to Tierra del Fuego. During this period, hunter-gatherer societies demonstrated remarkable cultural and adaptive diversity, particularly in subsistence strategies and technological innovations. The colonization of the Americas offers valuable insights into population dynamics, human–environment interactions, species extinctions, and adaptive capacities. From an interdisciplinary perspective that combines an isotopic analysis of megafaunal remains with archaeological evidence, this study examines human interactions with Pleistocene fauna in the south–central region of South America’s Southern Cone. Isotopic analyses provide information about the diets, adaptations, and climatic challenges faced by megafaunal communities. Archaeological evidence reveals that humans utilized megafauna and other Pleistocene species for food and tool production. These findings are supported by evidence such as cut marks and bone tools, but also by sealed sediment layers and/or indisputable associations of lithic artifacts. This research contributes to our understanding of human dispersal in the Southern Cone during the colonization of the Americas, shedding light on the regional environments and adaptive strategies of early populations. Full article

Although the Late Pleistocene glaciation history of the Fraser Lowland (BC, Canada) is relatively well studied, little is known about ice-flow directions during the last glaciation (Fraser glaciation). Lidar imagery from the western Fraser Lowland was used to identify and interpret previously unrecognized glacial landforms in a heavily urbanized and vegetated area. This indicates patterns of ice flow during the latest stage of the Fraser glaciation (Vashon stade) of the Cordilleran Ice Sheet. The imagery provides a picture of dominant SSE flow from the Strait of Georgia in the western part of the study area, and SSW flow from the southern Coast Mountain valleys in the eastern part, resulting in an overall southward flow, as documented in the uplands in the southern part of our study area. No evidence for a substantially different ice flow could be identified. Three new radiocarbon ages from the Sechelt area ca. 40 km northwest of the Fraser Lowland indicate a proximal ice margin in the Strait of Georgia already ca. 30 cal ka BP, well before the Coquitlam ice advance in the Fraser Lowland. These ages contribute to the unsolved discussion if this ice margin advanced onto the Fraser Lowland, yet further studies are needed. Full article

Based on 88 well-dated and high-resolution paleoclimate records, global and hemispheric stacks of the last deglacial climate were synthesized by utilizing the normalized average method. A sequential relationship between the West Antarctic Ice Sheet Divide ice core CO₂ concentration and the composited proxy-based global–hemispheric climate stacks was detected using the Wilcoxon rank-sum test and wavelet analysis. The results indicate that the climate stack of the Northern Hemisphere started to increase slowly before 22 kabp, possibly due to the enhancement of summer insolation at high northern latitudes, the onset of warming in the Southern Hemisphere occurred around 19 kabp, and the atmospheric CO₂ concentration began to raise around 18.1 kabp. This suggests that the change in northern high-latitude summer insolation was the initial trigger of the last deglaciation, and atmospheric CO₂ concentration was an internal feedback associated with global ocean circulation in the Earth’s system. Both the Wilcoxon rank-sum test and wavelet analysis showed that during the BØlling–AllerØd and the Younger Dryas periods there was no obvious asynchrony between the global climate and atmospheric CO₂ concentration, which perhaps implies a fast feedback–response mechanism. The seesawing changes in interhemispheric climate and the abrupt variations in the atmospheric CO₂ concentration could be explained by the influences of Atlantic meridional overturning circulation strength during the BØlling–AllerØd and the Younger Dryas periods. This reveals that Atlantic meridional overturning circulation played an important role in the course of the last deglaciation. Full article

A first attempt has been made to present a general composition of birds found in Chalcolithic settlements in the plains and lowlands of Bulgaria. Based on data from 21 settlements, 78 bird taxa (including 3 domestic forms) have been identified. Of these, 56 species have been identified to the species level. They constitute 13.4% (almost 1/7) of the 417 recorded bird species in the country. Aquatic birds (waterfowl, grebes, loons, herons, etc.) predominate (29 species). There are 12 species inhabiting woodland landscapes. Ten species are field/openland birds, and five are petrophilous species that inhabit rocky and stony habitats. Five species have disappeared as nesting in the country—bearded vulture, great bustard, common crane, colchic pheasant (native colchicus ssp.), and black grouse. These five species constitute 8.9% of the established composition of birds in the Chalcolithic settlements in the country. One extinct subspecies of the Eurasian coot has been described from one of these settlements. Full article

To study the long-term hydroclimate variability in the Satluj Basin, streamflow data was reconstructed using tree-ring width datasets from multiple taxa available from the Kullu Valley, western (Indian) Himalaya. Five ring-width tree-ring chronologies of three conifer tree taxa (Abies pindrow, Cedrus deodara, and Pinus roxburghii) significantly correlate with the streamflow during the southwest monsoon season. Based on this correlation, a 228-year (1787–2014 CE) June–August streamflow was reconstructed using average tree-ring chronology. The reconstruction accounts for 34.5% of the total variance of the gauge records from 1964 to 2011 CE. The annual reconstruction showed above-average high-flow periods during the periods 1808–1811, 1823–1827, 1833–1837, 1860–1863, 1876–1881, and 1986–1992 CE and below-average low-flow periods during the periods 1792–1798, 1817–1820, 1828–1832, 1853–1856, 1867–1870, 1944–1947, and 1959–1962 CE. Furthermore, a period of prominent prolonged below-average discharge in the low-frequency streamflow record is indicated during the periods 1788–1807, 1999–2011, 1966–1977, 1939–1949, and 1854–1864. The low-flow (dry periods) observed in the present streamflow reconstruction are coherent with other hydroclimatic reconstructions carried out from the local (Himachal Pradesh and Kashmir Himalaya) to the regional (Hindukush mountain range in Pakistan) level. The reconstruction shows occurrences of short (2.0–2.8 and 4.8–8.3 years) to medium (12.5 years) periodicities, which signify their teleconnections with large-scale climate variations such as the El Niño–Southern Oscillation and the Pacific Decadal Oscillation. Full article

According to the “suid gap” hypothesis, suids (Suidae, Mammalia) would have been absent from Europe between 1.8 and 1.2 Ma. This hypothesis has been influential owing to its putative implications for biochronology and paleoecology—Sus scrofa (the modern wild boar) would appear 1.2 Ma in a period of climatic and environmental changes, coinciding with the beginning of the Epivillafranchian and the Early–Middle Pleistocene Transition, and hominins—the arrival of Homo in western Europe would precede the “return” of pigs. However, the “suid gap” hypothesis is based on the wrong premises that suids are abundantly represented in the European fossil record before and after the “suid gap”, that this purported abundance is linked to the suid reproductive potential, and that the paleontological sites dated within the 1.8–1.2 Ma interval yielded enough remains to exclude the notion that the absence of suid is merely accidental. In a recent paper, it is shown that all these assumptions are erroneous and suid material is described from Peyrolles (France), which is dated at 1.47 ± 0.01 Ma, hence perfectly “filling the suid gap”. Some proposers of the “suid gap” hypothesis have now provided comments to this recent paper, casting doubt on the age of Peyrolles and reiterating the arbitrary statement that suids were commonly recorded and abundantly represented in the Pleistocene of Europe. There is no valid reason to question the homogeneity of the faunal assemblage of Peyrolles, which is indeed a key locality for the mammal biochronology of Europe, being the reference for MNQ 19. Suids of comparable chronology have also been found in Krimni (Greece). Moreover, the “suid gap” proposers are basically advocating the use of an interval biozone based on the temporary absence of Sus strozzii—a species not common in the Pleistocene of Europe—providing no ecological explanation for this gap, apart from speculating it would be due to competition with Homo. The defense of the “suid gap” seems motivated by its use from the “suid gap” proposers as a biochronological argument to contend that the localities of Orce in Spain (Barranco León D, Fuente Nueva 3, and Venta Micena) are older than 1.2 Ma, when they postulated suids would “reappear” in the fossil record. However, since the “suid gap” hypothesis was primarily proposed based on the absence of suids from the Orce sites (and, secondarily, from other sites biochronologically correlated with the localities of Orce, like Pirro Nord in Italy), this represents an evident example of circular reasoning. Full article