Discovery of the "Dueling Dinosaurs" and other significant dinosaur localities from remote and isolated exposures of the Hell Creek Formation in central Montana highlight the complexity of establishing stratigraphic context and correlating Hell Creek Formation fossil localities located within and outside of the type area. Stratigraphic correlation is particularly problematic for the lower two-thirds of the Hell Creek Formation, which generally lacks reliable biostratigraphic or magnetostratigraphic zonation and has no dated ash beds. To address these enduring issues for one of the most significant Upper Cretaceous terrestrial fossil-bearing units in North America, detailed stratigraphic sections were established on the Murray Ranch and on McGinnis Butte in central Montana and correlated with other published Hell Creek Formation localities via magnetostratigraphy, biostratigraphy, and radioisotopic dating of ash beds. Results indicate that the K-Pg boundary is not exposed in the study area; however, high-precision U-Pb CA-TIMS zircon ages for two newly discovered ash beds (66.929 ± 0.020 Ma and 66.850 ± 0.026 Ma, 2σ internal uncertainties) that bracket the "Dueling Dinosaurs" quarry provide the first absolute ages for the lower portion of the Hell Creek Formation anywhere. Bayesian age-stratigraphic modelling places the "Dueling Dinosaurs" depositional age at 66.897 + 0.023/-0.028 Ma and suggests that the age of the base of the formation is ~ 67.102 + 0.710/-0.173 Ma (or older) in the study area. Comparison of stratigraphic architecture within the study area with published sections in the type area suggests that named sandstone marker horizons used for lithostratigraphic and sequence stratigraphic correlation in the type area have limited utility for regional correlation and need to be used with caution.

The Falkland Islands, within the South Atlantic Ocean, display expansive Paleozoic sedimentary successions for which affinities with coeval depositional systems in southern Gondwana have been debated. New U-Pb zircon age spectra for ash and sandstone samples from the Falklands successions assist in elucidating relationships. Dating of ash samples shows the Port Sussex Formation (Falklands Islands) is younger than the lower Ecca Group of the Karoo Basin, not contemporaneous, as previously proposed. The Falklands and South African Paleozoic sequences differ only modestly, suggesting their accumulation and subsequent inversions were similar, but they represent discrete, basinal entities. Detrital zircon age spectra for samples from the Falklands successions show remarkable age-related comparability. Those from Silurian-earliest Permian samples are dominated by late Neoproterozoic to Cambrian (650-490 Ma) and mid-Mesoproterzoic-earliest Neoproterzoic (1235-940 Ma) age clusters. Populations from younger, post-glacial, Permian strata are dominated by arc-derived Permian clusters, consistent with the occurrence of ashfall horizons in the Port Sussex Formation, as well as subordinate older zircon grains matching the populations from the older successions. Age spectra from the Falkland successions match those of rock assemblages of the Terra Australis Orogen, which developed across southern Gondwana during the late Neoproterozoic and Paleozoic, indicating enduring, large scale, provenance linkages. Two overlapping Paleozoic superbasinal systems, distributed as linear belts extending for >6000 km are recognized parts of southern Gondwana, stratigraphically separated by a disconformity embracing much of the Carboniferous. A remarkably similar upper-plate subsidence response subduction along this margin is evident from the Silurian to Permian.

We describe Zoslestes gongori, a new species of non-placental eutherian mammal from Upper Cretaceous rocks of Zos Canyon in the Nemegt Basin of the western Gobi Desert, Mongolia. Zoslestes gongori is the largest known zalambdalestid. The Zos Canyon locality, Red Rum, that yielded the specimen is adjacent to beds that have produced several extinct crocodyliforms and the ornithischian dinosaur Haya griva. We provide the first formal stratigraphic description of these fossiliferous Zos Canyon rocks by naming and describing the Zos Formation for the unit at Red Rum. The Zos Formation has a distinct set of sedimentologic associations that differentiate it from the overlying Djadokhta Formation and also has the only fauna in the Nemegt Basin older than that of the Djadokhta Formation. We consider the Zos Formation roughly comparable in age to the Javkhlant Formation of the Eastern Gobi Desert, and likely older than the Alagteeg Formation of the Ulan Nur Basin. Zoslestes gongori is known from the holotype, a well-preserved posterior cranium, worn dentition, and fragmentary postcranial elements, and one referred specimen. The referred specimen consists of a damaged anterior skull and dentition, and a fragmentary left mandible with roots and alveoli, including an enlarged tooth resembling the elongate first lower incisor of zalambdalestids. Zoslestes shares several derived features with zalambdalestids, including the presence of a prominent entoglenoid process that, in ventral view, partly conceals the anteriorly-positioned postglenoid foramen, a large maxillary tuberosity, multiple hypoglossal foramina, a large, elongate i1 with a horizontally directed root extending deep within the mandible, lower molars with mesiodistally compressed trigonids and relatively wide talonids, a relatively large P4, and upper molars that are distinctly wider labiolingually than long mesiodistally and that are not interlocked mesiodistally. The significantly large size of Zoslestes and the large contribution of its jugal to the zygomatic process are autapomorphies distinguishing this taxon from other zalambdalestids. (c) 2025 Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Earth's sedimentary rock record is the primary archive for biotic, environmental, and climatic trends in deep time. Reconstructing these patterns requires a high-resolution geochronologic framework. This remains a significant challenge for many terrestrial ecosystems and an acute problem for some of the world's most important Mesozoic and Cenozoic fossil records. Overcoming this issue requires frontier approaches, such as directly dating fossils, long considered untenable. Here, we test the reliability of novel LA-ICP-MS U-Pb calcite dating and elemental mapping of non-avian dinosaur eggshells to produce accurate "burial ages." We directly dated fossilized dinosaur eggs recovered from the Western Interior Basin of North America, producing ages within 5% of high-precision ages from bracketing ash beds. We then directly dated dinosaur eggs from Upper Cretaceous strata within Mongolia's famous yet poorly age-constrained Gobi Basin, providing the first radioisotopic age for these deposits. Geochemical data coupled with trace elemental mapping indicate early uptake of uranium (U) in non-avian dinosaur eggshells via sediment contact, consistent with findings from Quaternary avian eggs. Calcified eggs, having evolved over 250 million years ago, offers a promising experimental methodology for determining the age of globally distributed fossil assemblages and recovering temporal, environmental, and ecological data from a single fossil.

Dozens of plesiosaur specimens have been recovered from the Upper Cretaceous of the Antarctic Peninsula, yet individuals that include skull material are extraordinarily rare. Here we report a new elasmosaurid partial skeleton from Cape Lamb of Vega Island (James Ross Island Group) that preserves significant parts of the cranium, mandible, and dentition, the semi-articulated anterior cervical series, several additional cervical vertebrae and ribs, caudal vertebrae, and four phalanges. Pertaining to an osteologically immature individual, the specimen is the second plesiosaur preserving skull bones to be reported from the uppermost (lower Maastrichtian) portion of the lower unit of the Cape Lamb Member of the Snow Hill Island Formation, and only the fourth to be discovered from the Cretaceous of Antarctica as a whole. Although most skeletal elements are represented only by natural molds, detailed observations and digital visualizations yield a considerable amount of anatomical information. Phylogenetic analysis recovered the specimen within the clade Weddellonectia, as the sister taxon of the highly derived, large-headed, possibly filter-feeding Aristonectinae. Ontogenetically independent differences in cervical vertebral morphology with Vegasaurus molyi-the only elasmosaurid species currently recognized from the Cape Lamb Member-indicate that the new specimen represents a second taxon of these long-necked marine reptiles within this stratigraphic unit.

Fossils representing Cretaceous lineages of crown clade birds (Aves) are exceptionally rare but are crucial to elucidating major ecological shifts across early avian divergences. Among the earliest known putative crown birds is Vegavis iaai1-5, a foot-propelled diver from the latest Cretaceous (69.2-68.4 million years ago)6 of Antarctica with controversial phylogenetic affinities2,7-10. Initially recovered by phylogenetic analyses as a stem anatid (ducks and closely related species)1,2,11, Vegavis has since been recovered as a stem member of Anseriformes (waterfowl)7-9, or outside Aves altogether10. Here we report a new, nearly complete skull of Vegavis that provides new insight into its feeding ecology and exhibits morphologies that support placement among waterfowl within crown-group birds. Vegavis has an avian beak (absence of teeth and reduced maxilla) and brain shape (hyperinflated cerebrum and ventrally shifted optic lobes). The temporal fossa is well excavated and expansive, indicating that this bird had hypertrophied jaw musculature. The beak is narrow and pointed, and the mandible lacks retroarticular processes. Together, these features comprise a feeding apparatus unlike that of any other known anseriform but like that of other extant birds that capture prey underwater (for example, grebes and loons). The Cretaceous occurrence of Vegavis, with a feeding ecology unique among known Galloanserae (waterfowl and landfowl), is further indication that the earliest anseriform divergences were marked by evolutionary experiments unrepresented in the extant diversity3,11-13.

In this study, we describe new results of excavations in the Dinaledi Subsystem of the Rising Star cave system, South Africa. In two areas within the Hill Antechamber and the Dinaledi Chamber, this work uncovered concentrations of abundant Homo naledi fossils including articulated, matrix-supported skeletal regions consistent with rapid covering by sediment prior to the decomposition of soft tissue. We additionally re-examine the spatial positioning of skeletal material and associated sediments within the Puzzle Box area, from which abundant H. naledi remains representing a minimum of six individuals were recovered in 2013 and 2014. Multiple lines of evidence exclude the hypothesis that skeletal remains from these three areas come from bodies that decomposed on the floor of the chamber or within a shallow depression prior to burial by sediments. The spatial positioning of skeletal material, the topography of the subsystem, and observations on sediments within and surrounding features exclude the hypothesis that rapid burial by sediment was a result of gravity-driven slumping or spontaneous movement of sediments. We present a minimal hypothesis of hominin cultural burial and test the evidence from all three areas, finding that this hypothesis is most compatible with the pattern of evidence. These results suggest that mortuary behavior, including cultural burial, was part of the repertoire of Homo naledi .

On September 18, 1996, Grand Staircase-Escalante National Monument (GSENM) became the first national monument managed by the US Bureau of Land Management (BLM) and one of the first to protect a landscape based partly on its opportunity for scientific discovery. Its creation was a watershed moment in public land management, because to meet the mandates for its first monument, BLM opted to implement unprecedented support of resource investigations for numerous natural and cultural sciences, including establishing its first ever in-house paleontological field program. The rationale for this was taken directly from the establishing presidential proclamation (6920) which called out GSENM’s untapped paleontological treasure trove as “world-class.” The proclamation also singled out the Late Cretaceous vertebrate fossil record of the Kaiparowits Plateau, largely known at the time through the pioneering work of Drs. Jeff Eaton and Rich Cifelli, who had spent years teasing out the mammalian evolutionary story preserved within. Their work on Mesozoic mammals, alongside sporadic work by other institutions (mainly the University of Utah and Brigham Young University) in the 1970s and 1980s, demonstrated that the Kaiparowits Plateau also held a substantial macrovertebrate record that included beautifully preserved dinosaur skeletons. However, a lack of coordinated effort and the difficult nature of fieldwork in the rugged badlands led to what can only be described as desultory results. The leverage that came with monument status, including logistical and financial support provided by BLM, made this resource more accessible to the paleontological community, stimulating a sudden burst of new field research and discovery. Initial, coordinated, and collaborative fossil inventories started in 2000 by joint BLM, Utah Museum of Natural History, Museum of Northern Arizona, and Utah Geological Survey teams led to a cascade of discoveries, including sites preserving plants, invertebrates, trace fossils, microvertebrates, and macrovertebrates, contextualized by new geological insights. Many of these new fossil finds represent species entirely new to science, with some sites preserving intact snapshots of Late Cretaceous ecosystems that are unmatched globally. Unique geologic conditions resulted in spectacular preservation, sometimes even including soft tissue traces. This renaissance in North American Late Cretaceous paleontology would not have been possible without the focused resources and effort facilitated by the creation of GSENM and the subsequent prioritization of inventory and basic research in its mission. In addition to the science, the public benefits of these efforts have been immense, providing opportunities for direct involvement in the scientific process through volunteer programs, training for several generations of future paleontologists and geologists, innumerable educational programs, and exposure in national and international media outlets through articles, television, and interviews. The collaborative and far-reaching paleontological effort at GSENM has highlighted an often overlooked aspect of public lands management: the importance of US public lands for scientific discovery and education.

The Campanian Two Medicine Formation of northwestern Montana, USA, is richly fossiliferous, and discoveries made within the unit over the past century have greatly advanced our appreciation of dinosaur paleobiology and evolution. Previously undifferentiated from a lithostratigraphic perspective, the formation is now subdivided into four new members that include (from base to top) (1) the Rock City Member, (2) the Shields Crossing Member, (3) the Hagans Crossing Member, and (4) the Flag Butte Member. These new formal units and their associated fossil occurrences are also now included in an age model founded on eight high-resolution chemical abrasion-isotope dilution-thermal ionization mass spectrometry (CA-ID-TIMS) U-Pb ages. New age data confirm that the Two Medicine Formation accumulated during much of the Campanian, with deposition spanning ca. 82.4 Ma to 74.4 Ma. New age data further indicate that a major reorganization of depositional systems, marked by a shift from predominantly lacustrine to alluvial facies and accompanied by a dramatic increase in accommodation, transpired near the base of the new Flag Butte Member at ca. 76.3 Ma. This change in depositional regime correlates in age with the Judith River- Belly River discontinuity, which marks the contact between the McClelland Ferry and Coal Ridge Members in the Judith River Formation and coincides with the onset of the Bearpaw transgression in north-central Montana. The new lithostratigraphic and chronostratigraphic framework for the Two Medicine Formation serves to contextualize and calibrate the formation's rich dinosaur fossil record, which can now be interrogated with increased clarity and precision. These results also provide ground truth for numerical models that explore the structure of the fossil record in relation to alluvial architecture and terrestrial sequence stratigraphy.

Long-term trends in fisheries catch are useful to monitor effects of fishing on wild populations. However, fisheries catch data are often aggregated in multi-species complexes, complicating assessments of individual species. Non-target species are often grouped together in this way, but this becomes problematic when increasingly common shifts toward targeting incidental species demand closer management focus at the species level. Species distribution models (SDMs) offer an under-utilised tool to allocate aggregated catch data among species for individual assessments. Here, we present a case study of two shovel-nosed lobsters (Thenus spp.), previously caught incidentally and recorded together in logbook records, to illustrate the design and use of catch allocation SDMs to untangle multi-species data for stock assessments of individual species. We demonstrate how catch allocation SDMs reveal previously masked species-specific catch trends from aggregated data and can identify shifts in fishing behaviour, e.g., changes in target species. Finally, we review key assumptions and limitations of this approach that may arise when applied across a broad geographic or taxonomic scope. Our aim is to provide a template to assist researchers and managers seeking to assess stocks of individual species using aggregated multi-species data.

Paleosols are unrivaled terrestrial archives of paleoclimatic, paleoecological, and paleoenvironmental conditions, yet their full utility and potential for unlocking critical information about past ecosystems, as well as their comparability with other records, is dependent upon the quality and thoroughness of such studies. To help standardize communication and compatibility in and between paleopedology studies, a systematic review was conducted with the goal of providing a “field-guide” for helping investigators approach paleosol identification, description, classification. A paleosol logging sheet template was developed to help standardize field data collection and note taking, which includes a list of 30 items that should ideally be described. An accompanying sample log sheet was also developed to assist with collection of key data during the sampling phase of paleosol investigations. Based on this review, we conclude that examination of fresh surfaces focusing on horizonation, color, structure (peds), pedogenic features, mineral accumulations, and bioturbation (burrows/chambers and root traces) is critical to all paleosol investigations and standard field testing should include color of the paleosol matrix and mottles present, carbonate content, redoximorphic conditions, and presence of organic matter. To further facilitate this work, we have illustrated and tabulated key paleosol features and classification schemes, including horizon determination and classification; ped determination and classification; mottle description; mineral accumulation description/morphology; burrow/chamber morphology and description; and rhizolith morphology and classification. In addition, a review of best practices in the collection of samples for subsequent laboratory analyses and paleoenvironmental interpretations is presented.

Habitat preferences influence partitioning in many marine taxa that can inform fisheries management. Despite this, little is known about how habitat partitioning contributes to spatial distributions in many commercially important species. This study aims to investigate habitat partitioning and influential variables affecting the distribution in Moreton Bay bug species Thenus parindicus and Thenus australiensis for the benefit of management on the east coast of Queensland, Australia. These Scyllarid lobsters spend much of their lives buried within sediment, but little research focuses on what influences the distribution of each species. In this study, a fishery-independent survey was conducted in a key commercial trawling area off the coast of Townsville to determine Thenus species distributions and habitat preferences. Variables used to examine the habitat preferences and distributions of both species included depth, sediment grain size, Trask sorting coefficient and calcium carbonate content. We found that all variables evaluated significantly affected species distributions. Multivariate analyses suggest that Trask sediment sorting coefficient and depth were the strongest influential variables. This contrasts with previous findings that mean grain size is the most important sediment parameter influencing Thenus distributions. The results indicate habitat partitioning between T. parindicus and T. australiensis but not habitat exclusion. These findings, along with the likely influential variables of species' distributions will help better understand the habitat ecology of these lobsters and inform management for the Moreton Bay bug fishery.

ABSTRACT The East African Rift System records a key interval in the evolution of modern African ecosystems, documenting significant floral changes and faunal dispersals in the context of environmental shifts. To date, Miocene-to-Pliocene data from eastern Africa have been derived primarily from richly fossiliferous rift basins along the far north of the Eastern Branch of the rift, with more limited windows emerging from the Malawi Rift and more recently, coastal Mozambique. Here, we present the first quantitative paleoclimate data for the Miocene–Pliocene transition from the Western Branch of the East African Rift System, based on analyses of paleosols from the Rukwa Rift Basin. Paleosols derived from the fossiliferous late Miocene–early Pliocene lower Lake Beds succession in southwestern Tanzania preserve a shallow lacustrine setting grading into a system of alluvial fans and braided rivers with abundant floodplain deposits. Paleoclimate reconstructions using bulk geochemistry and clay mineralogy reveal a highly seasonal, semiarid, mesic climate during the late Miocene, with increased moisture availability in the early Pliocene resulting in a shift to subhumid conditions. Stable-carbon-isotope composition of pedogenic carbonates document a woodland/bushland/shrubland paleoenvironment across the Miocene–Pliocene transition. Results support the presence of Pliocene subhumid to humid habitats, dominated by woody vegetation offering shade, food, and water for faunal dispersal along an inland corridor connecting northern segments of the East African Rift System with southern Africa.

A second K/Pg boundary interval in the northern sector of the Antarctic Peninsula on Vega Island has been proposed, yet cur-rent temporal resolution of these strata prohibits direct testing of this hypothesis. To not only test for the existence of a K/Pg boundary on Vega Island but also provide increased age resolution for the associated vertebrate fauna (e.g., marine reptiles, non -avian dinosaurs, and avian dinosaurs), the Vega Island succession was intensively re -sampled. Stratigraphic investigation of the Cape Lamb Member of the Snow Hill Island Formation, and in particular, the overlying Sandwich Bluff Member of the Lopez de Bertodano Formation, was conducted using biostratigraphy, strontium isotope stratig-raphy, magnetostratigraphy, and detrital zircon geochronology. These data indicate a Late Campanian-early Maastrichtian age for the Cape Lamb Member and present three possible correlations to the global polarity time scale (GPTS) for the overlying Sandwich Bluff Member. The most plau-sible correlation, which is consistent with biostratigraphy, detrital zircon geochronol-ogy, sequence stratigraphy, and all but one of the Sr-isotope ages, correlates the base of the section to C31N and the top of the section with C29N, which indicates that the K/Pg boundary passes through the top of the unit. A second, less plausible option conflicts with the biostratigraphy and depends on a series of poorly defined magnetic reversals in the upper part of the stratigraphy that also cor-relates the section between C31N and C29R and again indicates an inclusive K/Pg bound-ary interval. The least likely correlation, which depends on favoring only a single Sr -isotope age at the top of the section over bio-stratigraphy, correlates the section between C31N and C30N and is inconsistent with an included K/Pg boundary interval. Although our preferred correlation is well supported, we failed to identify an Ir-anomaly, spher-ules/impact ejecta, or other direct evidence typically used to define the precise position of a K/Pg boundary on Vega Island. This study does, however, confirm that Vegavis, from the base of the Sandwich Bluff Member, is the oldest (69.2-68.4 Ma) phylogenetically placed representative of the avian crown clade, and that marine vertebrates and non -avian dinosaurs persisted in Antarctica up to the terminal Cretaceous.

Abstract The Canning Basin is a prospective hydrocarbon frontier basin and is unusual for having limited offshore seismic and well data in comparison with its onshore extent. In this study, seismic mapping was conducted to better resolve the continuity of 13 key stratigraphic units from onshore to offshore to delineate prospective offshore hydrocarbon-bearing units, and better understand the distribution of mafic igneous units that can compartmentalise migration pathways and influence heat flow. The offshore Canning Basin strata are poorly constrained in six wells with limited seismic coverage; hence data availability was bolstered by integrating data from the onshore portion of the basin and adjacent basins into a single 3D seismic stratigraphic model. This model integrates over 10 000 km of historical 2D seismic data and 23 exploration wells to allow mapping of key stratal surfaces. Mapped seismic horizons were used to construct isochores and regional cross-sections. Seven of the 13 units were mapped offshore for the first time, revealing that the onshore and offshore stratigraphy are similar, albeit with some minor differences, and mafic igneous units are more interconnected than previously documented whereby they may constitute a mafic magmatic province. These basin-scale maps provide a framework for future research and resource exploration in the Canning Basin. To better understand the basin’s geological evolution, tectonic history and petroleum prospectivity, additional well data are needed in the offshore Canning Basin where Ordovician strata have yet to be sampled. Key Points Coastlines act as barriers that can prevent parity of stratigraphic interpretations and geoscience data acquisition for adjacent onshore, offshore areas. This study features seismic stratigraphic mapping of 13 key units in the Canning Basin coastal area, including seven units mapped continuously from onshore to offshore for the first time. This research delivers a framework for future exploration and a better understanding of the Canning Basin’s geological history.

Background: Maternal prenatal exposure to air pollution has been associated with adverse birth outcomes. However, previous studies focused on a priori time intervals such as trimesters reported inconsistent associations. Objectives: We investigated time-varying vulnerability of birth weight to fine particulate matter (PM2.5) and nitrogen dioxide (NO2) using flexible time intervals. Methods: We analyzed 1,300 live, full-term births from Maternal–Infant Research on Environmental Chemicals, a Canadian prospective pregnancy cohort spanning 10 cities (2008–2011). Daily PM2.5 and NO2 concentrations were estimated from ground-level monitoring, satellite models, and land-use regression, and assigned to participants from pre-pregnancy through delivery. We developed a flexible two-stage modeling method—using a Bayesian Metropolis–Hastings algorithm and empirical density threshold—to identify time-dependent vulnerability to air pollution without specifying exposure periods a priori. This approach identified critical windows with varying lengths (2–363 days) and critical windows that fell within, or straddled, predetermined time periods (i.e., trimesters). We adjusted the models for detailed infant and maternal covariates. Results: Critical windows associated with reduced birth weight were identified during mid- to late-pregnancy for both PM2.5 and NO2: –6 g (95% credible interval: –11, –1 g) and –5 g (–10, –0.1 g) per µg/m3 PM2.5 during gestational days 91–139 and 249–272, respectively; and –3 g (–5, –1 g) per ppb NO2 during days 55–145. Discussion: We used a novel, flexible selection method to identify critical windows when maternal exposures to air pollution were associated with decrements in birth weight. Our results suggest that air pollution impacts on fetal development may not be adequately captured by trimester-based analyses.

During the Early Cretaceous, Australia was flooded by the epicontinental Eromanga Sea, deposits of which occur across the Great Australian Superbasin. However, the mid‐Cretaceous retreat of this shallow sea, and the resultant palaeogeographic and sediment distribution patterns, are poorly understood. This study chronicles the Eromanga Sea's northward regression through the Carpentaria Basin as captured in the sedimentary record of the Normanton Formation. We achieve this by integrating sedimentary facies analysis of cores from across the Carpentaria Basin with palynology, sandstone petrography and U‐Pb detrital zircon geochronology. Results indicate that the Normanton Formation was deposited between ca. 100 and 96 Ma, and that it represents a large, northward‐prograding, likely river‐dominated delta system. The unit's volcanoclastic nature is exhibited through abundant lithic volcanics and devitrified glass, with a prominent, near‐depositional detrital zircon population attributed to a proximal continental magmatic arc‐derived source hypothesised to parallel the eastern seaboard of Australia at this time. The Normanton Formation is temporally correlative with the lower‐middle portions of the similarly volcanoclastic Winton Formation in the Eromanga Basin, which drained southwards into the Cenomanian‐Santonian Ceduna River Delta system. However, Normanton Formation strata display subtly different provenance signatures and drainage patterns, indicating input from similar, but likely more northern source terrains than much of the contemporaneous Winton Formation. These sediments were unlikely recycled southwards into the Ceduna Delta like those of the Winton Formation; rather they drained northward following the retreat of the Eromanga Sea through the Carpentaria Basin, indicating a Cretaceous drainage divide between two river systems, with distinct northern and southern drainage catchments. The mid‐Cretaceous palaeogeography of eastern Australia is analogous to that of the Late Cretaceous Western Interior Seaway of North America, in which the retreat of a shallow epicontinental sea is marked by the rapid deposition and progradation of multiple large, geographically distinct clastic wedges.

Rising Star Cave in the Cradle of Humankind, South Africa, contains one of the richest hominin-bearing deposits in the world, and is the type locality for the Homo naledi fossils. This paper provides a stratigraphic and geochronological framework, within which published and future fossil finds from Rising Star Cave can be placed. Detailed mapping of flowstone horizons combined with new age constraints based on both U-Th disequilibrium and U-234/U-238 dates and one new OSL date help define seven periods of flowstone formation that punctuate episodes of clastic sedimentation and erosion. Clastic sediments entered the cave through an opening in the roof of the Postbox Chamber from about 600 ka onward, until the opening was choked by coarse breccia blocks, probably sometime after 180 ka. Depositional and erosional events changed the internal morphology of the cave chambers over time, and thereby changed the access route into the Dinaledi Chamber where the bulk of the H. naledi fossils were found. Periods of pervasive flowstone formation at all levels of the cave occurred at >600 ka, similar to 500-400 ka, similar to 225-190 ka and similar to 110-90 ka. Additional periods of localised flowstone growth restricted to individual chambers (or parts thereof) occurred at similar to 300 ka, similar to 160 ka, similar to 70 ka, similar to 50 ka, similar to 30 ka, and similar to 10 ka. Flowstone horizons bracket sedimentary units that include a variety of sediment types that changed with time. The oldest flowstones overlie lithified mud clast breccias (LMCB), which were partly eroded before they were covered by externally derived laminated orange sands (LOS) and 500-400 ka flowstones. These flowstones and sands were removed between 290 ka and 225 ka, with sediment transported to deeper parts of the cave via erosion channels characterised by massive orange sands (MOS). In this period of time, the access route into the Dinaledi Chamber may have further changed due to the collapse of the Dragon's Back block. Deposition of laminated orange-red mud (LORM) from suspension occurred between 225 and 190 ka and temporally overlaps with widespread flowstone formation around similar to 225 ka and similar to 200 ka. The LORM deposits were largely removed from the upper chambers by similar to 110 ka, before the youngest group of flowstones formed in the cave; some of which are still growing today. The U-Th ages from Rising Star Cave, combined with other dating constraints reveal age clusters of flowstone formation, which coincided with warmer interglacial or interstadial periods. The patterns recognised in Rising Star Cave overlap with periods of flowstone formation recognised in nearby caves in the Cradle of Humankind, thereby confirming a regional climatic control on flowstone growth in caves during the past 500 ky. The new ages further constrain the minimum age of H. naledi to similar to 241 ka. Thus, H. naledi entered the cave between 241 ka and 335 ka, during a glacial period, at which time clastic sediments inside the cave were undergoing erosion. H. naledi would probably have entered the cave through an access point in the roof of the Postbox Chamber and made its way along a SW trending fracture towards the Dragon's Back and Dinaledi Chambers.