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During the Pleistocene-Holocene transition, the dominant mammoth steppe ecosystem across northern Eurasia vanished, in parallel with megafauna extinctions. However, plant extinction patterns are rarely detected due to lack of identifiable fossil records. Here, we introduce a method for detection of plant taxa loss at regional (extirpation) to potentially global scale (extinction) and their causes, as determined from ancient plant DNA metabarcoding in sediment cores (sedaDNA) from lakes in Siberia and Alaska over the past 28,000 years. Overall, potential plant extinctions track changes in temperature, in vegetation, and in megafauna extinctions at the Pleistocene-Holocene transition. Estimated potential plant extinction rates were 1.7–5.9 extinctions per million species years (E/MSY), above background extinction rates but below modern estimates. Major potential plant extinction events were detected around 17,000 and 9000 years ago which lag maximum vegetation turnover. Our results indicate that herbaceous taxa and taxa contributing less to beta diversity are more vulnerable to extinction. While the robustness of the estimates will increase as DNA reference libraries and ancient sedaDNA data expand, the available data support that plants are more resilient to environmental changes than mammals. Plant extinctions during the Pleistocene-Holocene transition are poorly documented in the fossil record. Here, the authors present a method to detect plant taxa loss from sedaDNA and demonstrate that herbaceous taxa and taxa contributing less to beta diversity are less vulnerable. [ABSTRACT FROM AUTHOR]

The temporal range of eodiscids and agnostoid arthropods overlaps with several early Paleozoic geological events of evolutionary significance. However, the responses of agnostids to these events and how the perturbations associated with them (both abiotic and/or biotic) may have impacted agnostids remain uncertain. To address this uncertainty, we employ geometric morphometrics to reconstruct morphospace occupation for agnostids, thereby elucidating their evolutionary response to geological events during the early Paleozoic. The results indicate that maximum morphospace occupation was reached by Cambrian Series 2 and then declined soon thereafter. Subsequent reductions in agnostid morphospace occupation coincide not only with significant abiotic changes and associated extinction events, such as the Botoman–Toyonian Extinctions (BTEs), the Redlichiid–Olenellid Extinction Carbon Isotope Excursion (ROECE), the Drumian Carbon Isotope Excursion (DICE), and the Steptoean Positive Carbon Isotope Excursion event (SPICE), but also with major evolutionary episodes, such as the Great Ordovician Biodiversification Event (GOBE). These repeated and periodic declines in agnostid morphological diversity following Cambrian Series 2 suggest that the extinction of agnostids reflects the culmination of an episodic reduction in morphological occupancy for agnostids rather than a singular, sudden event. Accordingly, it cannot be tied to a single cause, either abiotic or biotic. [ABSTRACT FROM AUTHOR]

Fossiliferous carbonate concretions are commonly found in sediments deposited in the Late Cretaceous Western Interior Seaway. Although concretions are diagenetic features, well-preserved fossils from within them have been instrumental in reconstructing the temperature and d18O value of Western Interior Seaway seawater, which is essential for accurate reconstruction of Late Cretaceous climate. Here, we constrain formation conditions of Late Campanian and early Maastrichtian carbonate concretions by combining triple oxygen isotope measurements with carbonate clumped isotope paleothermometry on different carbonate phases within the concretions. We measured both fossil skeletal aragonite and sparry calcite infill from cracks and within macrofossil voids to evaluate differences between "primary" and "altered" geochemical signals. Based on the two temperature-sensitive isotope systems of the primary fossil shell aragonite, the temperature of the Western Interior Seaway was between 20 °C and 40 °C and was likely thermally stratified during the Campanian. The reconstructed d18Oseawater values of ~-1‰ for Campanian Western Interior Seaway waters are similar to those expected for the open ocean during greenhouse climates, while the Maastrichtian Western Interior Seaway may have been more restricted, with a d18Oseawater value of ~2‰, which reflects more evaporative conditions. We reconstructed the diagenetic history of the sparry infill and altered fossils using a fluid-rock mixing model. Alteration temperature, alteration fluid d18O value, and the initial formation temperature were calculated by applying the fluid-rock mixing model to a particle swarm optimization algorithm. We found a different range of initial formation temperatures between the Campanian (25-38 °C) and Maastrichtian (9-28 °C). We also found that alteration in the presence of light meteoric fluids (d18O ≈ -10‰) is required to explain both the sparry infill and the altered fossil isotopic values. Based on our results, both lithification and alteration of the carbonates occurred soon after burial, and light meteoric fluids support prior findings that high-topographic relief existed on the western margin of the Western Interior Seaway during the Late Cretaceous. As one of the first studies to apply these techniques in concert and across multiple mineralogical phases within samples, our results provide important constraints on paleoenvironmental conditions in an enigmatic ocean system and will improve interpretations of the overall health of ecosystems leading into the end-Cretaceous mass extinction. [ABSTRACT FROM AUTHOR]

This work presents four novel entropy-based indices for measuring the community evolution of developer social networks (DSNs) in open source software (OSS) projects. The proposed indices offer a quantitative measure of community split, shrink, merge, and expand events. The indices have proven properties like monotonicity, and they have defined maximum and minimum values that signify meaningful scenarios. These indices can be combined to describe complex community evolution events such as emergence and extinction. Expanding upon these indices, this research proposes a novel machine learning approach, leveraging shapelet mining, to unearth representative patterns of community evolution. The results from real-world OSS projects show that these indices effectively capture various community evolution behaviors with a 94.1% accuracy compared to existing work. They also predict OSS team productivity with a 0.718 accuracy. With the shapelet mining and learning framework, the indices can identify patterns of community evolution and predict the survival of OSS projects with 93% accuracy 3 months before the projects' last observed commits. The findings highlight the potential of these entropy-based indices for understanding OSS project status and predicting future trends, which are valuable for supporting future research on DSNs and OSS communities. [ABSTRACT FROM AUTHOR]

Alongside the Chicxulub meteorite impact, Deccan volcanism is considered a primary trigger for the Cretaceous-Paleogene (K-Pg) mass extinction. Models suggest that volcanic outgassing of carbon and sulfur--potent environmental stressors--drove global temperature change, but the relative timing, duration, and magnitude of such change remains uncertain. Here, we use the organic paleothermometer MBT'5me and the carbon-isotope composition of two K-Pg-spanning lignites from the western Unites States, to test models of volcanogenic air temperature change in the ~100 kyr before the mass extinction. Our records show long-term warming of ~3°C, probably driven by Deccan CO2 emissions, and reveal a transient (<10 kyr) ~5°C cooling event, coinciding with the peak of the Poladpur "pulse" of Deccan eruption ~30 kyr before the K-Pg boundary. This cooling was likely caused by the aerosolization of volcanogenic sulfur. Temperatures returned to pre-event values before the mass extinction, suggesting that, from the terrestrial perspective, volcanogenic climate change was not the primary cause of K-Pg extinction. [ABSTRACT FROM AUTHOR]

At the end of the Middle Permian Guadeloupe series, the Chinese region recorded the only internationally recognized large igneous provincial eruption event, known as the Emeishan LIP. The Yangtze region of South China records a series of short and almost synchronous geological events that accompanied the development of bio-geological events such as large-scale magmatic intrusion, plate rupture, magnetic pole anomalies, and ecological collapse. These events ultimately triggered the extinction of living organisms. However, the current study leaves several questions unanswered. What was the sequence of geological events? Are the global records of these events synchronized? What is the causal relationship between these events? This study discusses the sedimentary responses to various geological events using biofossils, fluid inclusion, carbon isotopic analysis, and astrochronological analysis. The results reflect the following: (i) Mantle plumes: Mantle plumes act as pathways for heated fluids to ascend from the Earth's interior. The mantle plume reached the Moho surface in the mid-Wordian and affected the magnetic field at the Earth's surface; (ii) Magnetic pole anomalies: The anomaly of the Earth's magnetic poles appeared in the mid-Wordian stage, causing the originally stable plates to begin to split. The sea level changes dramatically, and the ancient landform pattern changes dramatically; (iii) Plate rupture: The rifting of plates accelerated the activity of deep hydrothermal fluids; the hydrothermal fluid gradually infiltrated the paleo-ocean after the J. altudaensis zone; (iv) Emeishan LIP: The volcano erupted at 260 Ma, and eventually led to the mass extinction. We aim to identify the initial triggers of various geological events by analyzing the sedimentary record. [ABSTRACT FROM AUTHOR]

The causes of heterogeneity in evolutionary rates are a key question in macroevolution. Origination and extinction rates are closely related to abiotic factors, such as climate 1,2 and geography, 3,4 as well as biotic factors such as taxonomic richness 5,6 and morphology, 7 which are influenced by phylogeny. 8,9 Studies on the relationship between morphology and macroevolution have focused on morphological traits, including body size, 6,7,9 shape, 10 color, 11,12 and complexity, 13,14,15 and have proposed biological laws, such as the zero-force evolutionary law 16 and Cope's rule. 17 However, the relationship between morphological complexity and turnover rates remains poorly defined because of the lack of suitable measures for various subjects. 18,19 Here, we establish a quantitative method, the two-dimensional ornamentation index (2D-OI), which allows the description of the ornamental complexity of ammonoids. Ammonoids are one of the most abundant and well-studied fossil groups, with complex conch structures. 20 Ammonoids display some similarities with trilobites and mammals 21,22 in terms of their high evolutionary rates; however, the underlying mechanisms remain elusive. Moreover, ammonoids exhibit marked heterogeneity in turnover rates across spatiotemporal scales 23 and clades, 23,24 making them key clades for investigating the relationship between turnover rates and morphological complexity. The results show that morphologically complex genera and species often have higher origination and extinction rates than morphologically simple taxa. Diversity fluctuations of taxa with complex ornamentation generally overimprint and control the overall net diversification rates of ammonoids. This double-edged sword of rapid evolution and increased extinction risk driven by complex morphologies has significant implications for our understanding of how species survive over geological timescales. • New method ("2D-OI") to estimate the ornamentation complexity in shelled animals • Complex morphologic ammonoids generally exhibit shorter longevity than simple taxa • Complex morphologic taxa have higher origination and extinction rates than simple taxa • Complex taxa dominate overall fluctuations in ammonoid diversification rates Miao et al. show that morphologically complex ammonoid genera and species generally have shorter longevity and faster rates of turnover than morphologically simple taxa. The diversification rate of taxa with complex morphology controls the apparent overall diversification fluctuations of ammonoids. [ABSTRACT FROM AUTHOR]

The miniaturization of organisms during the Permian-Triassic mass extinction, as an ecological strategy in response to environmental devastation, has been widely recognized in diverse marine invertebrates. Previous studies on the extinction process and miniaturization of foraminifers in the Permian-Triassic interval have relied on the fossil record of the low-latitude Paleotethys or a global database, although data and materials from the high-latitude Neotethys region are still rare. To reveal the evolutionary patterns and spatial variability of foraminifers at different latitudes and paleogeographic contexts, here we investigated the fossil distribution and size variation of foraminifers in the Selong Section of southern Tibet, located in the mid-latitude Neotethys of the Southern Hemisphere during the Permian-Triassic transition. The results show that the foraminifer of the Selong Section experienced a two-pulsed extinction (total species extinction rate of 71%), consistent with the time in South China but with a lower magnitude of extinction. Meanwhile, the data show that foraminiferal test volume was significantly miniaturized following the first pulse of extinction event: the mean size of post-extinction foraminifer was only 15% of that in the pre-extinction, mainly reflected by the disappearance of large forms as well as occurrences of smaller survivors and originators. Combined with the South China record, size data from southern Tibet indicate that the miniaturization of foraminifera is synchronous in the Paleotethys and Neotethys but smaller in magnitude in the Neotethys. We propose that ocean anoxia and acidification may be the environmental pressures leading to local and global foraminiferal miniaturizations, along with global warming, which might play a dominant role. [ABSTRACT FROM AUTHOR]

Polyneoptera includes some of the best-known insect species, such as grasshoppers and cockroaches. While the evolutionary history of many Polyneoptera orders has been thoroughly explored, others have been partially overlooked. This is the case with Xenonomia, a clade consisting of two species-poor insect orders with a relatively recent taxonomic history: Mantophasmatodea and Grylloblattodea. Here, we provide a temporal framework for their evolution, leveraging a mitochondrial phylogenomics approach encompassing all Polyneoptera orders. To strengthen the confidence in our divergence times estimation, we specifically focused on the possible impact of phylogenetic biases, such as long branch attraction, the influence of specific fossil priors, the use of nucleotide or amino acid alignments, and different clock models. Our results consistently support the origin of Xenonomia during the Carboniferous, and the divergence between the two orders is inferred to have happened before the Permian. While Grylloblattodea diversification is inferred to have occurred earlier than that of Mantophasmatodea, extant species of both orders most likely diversified after the Permian/Triassic and Triassic/Jurassic mass extinctions. Our molecular divergence time analyses complement the fossil record and support the ancient relict status of these two polyneopteran orders. [ABSTRACT FROM AUTHOR]

The term 'sixth mass extinction' has become synonymous with the current biodiversity crisis. However, despite a general agreement that current biodiversity declines are severe, no consensus has been reached on whether this constitutes a 'mass extinction event', and thus, whether our current situation is comparable to the catastrophic extinction events of deep time. Here, we suggest that our inability to gauge whether the current biodiversity crisis is a mass extinction event may lie less in quantifiable evidence and more in the language used to define such events. We highlight areas of linguistic contention, vagueness and epistemic dispute, and discuss the role of post hoc decision‐making and language in shaping our understanding and communication of biodiversity loss. Our discussion raises larger questions about how we communicate science to the public, funders and other scientists, and how we use language to both shape awareness and leverage action. The term 'sixth mass extinction' used for the current biodiversity crisis lacks consensus on its accuracy. The epistemic dispute stemming from this ambiguity underscores the importance of clear communication in shaping public awareness and spurring action regarding biodiversity loss. [ABSTRACT FROM AUTHOR]

Habitat association has been proposed to affect evolutionary dynamics through its control on dispersal propensity, which is considered a key trait for lineage survival in habitats of low durational stability. The Habitat Constraint hypothesis predicts different micro‐ and macroevolutionary patterns for stable versus dynamic habitat specialists, but the empirical evidence remains controversial and in insects mostly derives from winged lineages. We here use genome‐wide SNP data to assess the effect of habitat association on the population dynamics of two closely related flightless lineages of the genus Eutagenia (Coleoptera: Tenebrionidae), which are co‐distributed across the Cyclades islands in the Eastern Mediterranean but are associated with habitat types of different presumed stability: the psammophilous lineage is associated with dynamic sandy coastal habitats, while the geophilous lineage is associated with comparatively stable compact soil habitats. Our comparative population genomic and demographic analyses support higher inter‐island gene flow in the psammophilous lineage, presumably due to the physical properties of dynamic sand‐dune habitats that promote passive dispersal. We also find consistent bottlenecks in the psammophilous demes, suggesting that lineage evolution in the dynamic habitat is punctuated by local extinction and recolonisation events. The inferred demographic processes are surprisingly uniform among psammophilous demes, but vary considerably among geophilous demes depending on historical island connectivity, indicating more stringent constraints on the dynamic habitat lineage. This study extends the Habitat Constraint hypothesis by demonstrating that selection on dispersal traits is not the only mechanism that can drive consistent differences in evolutionary dynamics between stable versus dynamic habitat specialists. [ABSTRACT FROM AUTHOR]

In the face of unprecedented global transformations, unravelling the intricate mechanisms governing biodiversity patterns is imperative for predicting and interpreting species responses. An important element in this interplay is fragmentation and the spatial mosaic or arrangement of suitable sites within the landscape. Beyond its well-documented impact on biodiversity loss, fragmented landscapes also influence the origin of biodiversity, by influencing speciation dynamics. This research employs a model that integrates spatial configuration and dispersal abilities of individuals to investigate the impact of landscape configuration on species' evolutionary trajectories. Specifically, we propose a microevolutionary model where individuals are characterized by their dispersal ability and a genome, allowing population evolution and diversification. Space is explicitly characterized by suitable and unsuitable sites that define fragmented landscapes. Our model demonstrates how intermediate dispersal abilities enhance diversification. However, simulations of more fragmented landscapes result in a lower total number of individuals and a lower percentage of occupied sites by individuals, particularly when species have limited dispersal abilities. Furthermore, we have found that intermediate levels of fragmentation can stimulate greater species richness, while higher levels of speciation and extinction events tend to occur under higher fragmentations. Our results also show a non-monotonic dependence of richness on dispersal, supporting the intermediate dispersal hypothesis as a promotor of diversification, demonstrating the synergistic effects of landscape configuration and species dispersal ability in the processes of speciation, extinction, and diversification. This impact of fragmentation poses a real challenge for biodiversity in the context of a dynamic world. [ABSTRACT FROM AUTHOR]

The processes that generate biodiversity start on a microevolutionary scale, where each individual's history can impact the species' history. This manuscript presents a theoretical study that examines the macroevolutionary patterns that emerge from the microevolutionary dynamics of populations inhabiting two patches. The model is neutral, meaning that neither survival nor reproduction depends on a fixed genotype, yet individuals must have minimal genetic similarity to reproduce. We used historical sea level oscillation over the past 800 thousand years to hypothesize periods when individuals could migrate from one patch to another. In our study, we keep track of each speciation and extinction event, build the complete and extant phylogenies, and characterize the macroevolutionary patterns regarding phylogeny balance, acceleration of speciation, and crown age. We also evaluate ecological patterns: richness, beta diversity, and species distribution symmetry. The balance of the complete phylogeny can be a sign of the speciation mode, contrasting speciation induced by migration and isolation (vicariance). The acceleration of the speciation process is also affected by the geographical barriers and the duration of the isolation period, with high isolation times leading to accelerated speciation. We report the correlation between ecological and macroevolutionary patterns and show it decreases with the time spent in isolation. We discuss, in light of our results, the challenge of integrating present-time community ecology with macroevolutionary patterns. [ABSTRACT FROM AUTHOR]

Simple Summary: Primary themes in intergenerational justice are a healthy environment, the perpetuation of Earth's biodiversity, and the sustainable management of the biosphere. These goals demand transformative changes to biodiversity management, especially when considering the predicted sixth mass extinction. Reproduction and advanced biotechnologies, biobanks of germplasm and somatic cells, and conservation breeding programs (RBCs) provide a transformative change to perpetuate biodiversity irrespective of environmental targets, ecosystem collapses, and other sixth mass extinction drivers. Future potentials for RBCs include assisted evolution, species restoration, and the extension of the biosphere through interplanetary and interstellar colonization. We address these themes with amphibian models to introduce the MDPI Special Issue, The Sixth Mass Extinction and Species Sustainability through Reproduction and Advanced Biotechnologies, Biobanking, and Conservation Breeding Programs. Primary themes in intergenerational justice are a healthy environment, the perpetuation of Earth's biodiversity, and the sustainable management of the biosphere. However, the current rate of species declines globally, ecosystem collapses driven by accelerating and catastrophic global heating, and a plethora of other threats preclude the ability of habitat protection alone to prevent a cascade of amphibian and other species mass extinctions. Reproduction and advanced biotechnologies, biobanking of germplasm and somatic cells, and conservation breeding programs (RBCs) offer a transformative change in biodiversity management. This change can economically and reliably perpetuate species irrespective of environmental targets and extend to satisfy humanity's future needs as the biosphere expands into space. Currently applied RBCs include the hormonal stimulation of reproduction, the collection and refrigerated storage of sperm and oocytes, sperm cryopreservation, in vitro fertilization, and biobanking of germplasm and somatic cells. The benefits of advanced biotechnologies in development, such as assisted evolution and cloning for species adaptation or restoration, have yet to be fully realized. We broaden our discussion to include genetic management, political and cultural engagement, and future applications, including the extension of the biosphere through humanity's interplanetary and interstellar colonization. The development and application of RBCs raise intriguing ethical, theological, and philosophical issues. We address these themes with amphibian models to introduce the Multidisciplinary Digital Publishing Institute Special Issue, The Sixth Mass Extinction and Species Sustainability through Reproduction Biotechnologies, Biobanking, and Conservation Breeding Programs. [ABSTRACT FROM AUTHOR]

Evolutionary relationships of fossil gastropods have largely been inferred using taxonomic systematics. Phylogenetic relationships between extinct gastropod groups and their relationship to extant groups are largely unresolved. Here we reconstruct the phylogeny of Pleurotomariida, which has the longest fossil record among extant gastropod clades and represents one of the most diverse Palaeozoic gastropod groups. Bayesian (fossilized birth–death [FBD] model) and parsimony analyses were performed using 93 morphological shell characters comprising 109 pleurotomariidan species representing 80 genera/subgenera ranging from the Ordovician to Recent. Parsimony analysis failed to reconstruct stratigraphically congruent trees and many nodes have poor support. The FBD model incorporates the stratigraphical ages of taxa for tree reconstruction and therefore better fits the stratigraphical record. According to the FBD phylogeny, Pleurotomariida was represented by three distinct lineages during the Palaeozoic: Eotomariini, Wortheniellini and Pleurotomariini. Pleurotomariini and Wortheniellini survived the end-Permian mass extinction. Although Wortheniellini showed a higher diversification during the Triassic recovery period, only Pleurotomariini survived until the present day, suggesting that resilience to extinction was not dependent on diversification dynamics in this clade. The FBD analysis indicates that groups that have an exclusively Triassic fossil record originated during the Permian and that the origination and extinction rates increased from the Ordovician to the Jurassic and dropped subsequently. Sampling standardized diversity analysis of Pleurotomariida corroborates that they were one of the most diverse gastropod groups in the late Palaeozoic and that their diversity significantly dropped after the end-Permian mass extinction. Early ontogenetic shell characters are more conservative (phylogenetically more informative) compared to late ontogenetic shell characters. In contrast to previous assumptions, axial characters are not more homoplastic than spiral shell characters, as indicated by higher consistency index values. The data further revealed that adult gastropod shell size depends significantly on the protoconch size and the initial whorl size. [ABSTRACT FROM AUTHOR]

The diversification of Palaeozoic stromatoporoid sponges was interrupted by the Late Ordovician glaciation, which caused the first of the five major extinctions during the Phanerozoic. Glaciation and the subsequent expansion of anoxia during deglaciation are interpreted to have resulted in a persistent scarcity of stromatoporoids during the Hirnantian. Previously, Hirnantian stromatoporoids were only known from two regions: Estonia in Baltica and Anticosti Island in eastern Laurentia. Here we report stromatoporoids from the upper Hirnantian Shiqian Formation of South China, adding to the rare fossil record of Hirnantian stromatoporoids. Three new stromatoporoid taxa are identified: Ecclimadictyon ancipitum Jeon sp. nov., Camptodictyon contortus Jeon & Kershaw sp. nov., and Cystostroma rallus Jeon sp. nov. The appearance of these stromatoporoids in South China is stratigraphically later than solitary rugose corals, but coincides with tabulate corals in the aftermath of the end-Ordovician mass extinction. Compared to the wider palaeogeographical and environmental distributions of rugose and tabulate corals during the Hirnantian, stromatoporoids presumably had a narrower environmental tolerance. The stromatoporoid assemblage in South China during the Hirnantian is dominated by clathrodictyids, which exhibit similar faunal patterns to those found in Baltica and Laurentia during the same period. The rise of clathrodictyid-dominated assemblages began in the middle to late Katian of the Late Ordovician, particularly in peri-Gondwanan regions, and rapidly expanded worldwide during the subsequent Hirnantian and Silurian onwards. The Late Ordovician glaciation significantly hastened the global Ordovician–Silurian stromatoporoid transition, as evidenced by the disappearance of numerous labechiid-type stromatoporoids and the expansion of clathrodictyid-type stromatoporoids in the Hirnantian and the subsequent Silurian. [ABSTRACT FROM AUTHOR]

During the Late Ordovician period, changes in climate and mass extinctions were observed; however, the factors influencing these phenomena have not been fully understood. In order to understand the relationships among redox water conditions, climates, and mass extinctions in the Late Ordovician, this study analyzes the chemical index of alteration (CIA) in shales and 87Sr/86Sr in carbonate leachates as proxies of changes in chemical weathering intensity and chemical weathering rate in the Late Ordovician (mainly from Katian to Hirnantian). The results show that an enhanced chemical weathering rate (increased 87Sr/86Sr ratios) and decreased chemical weathering intensity (decreased CIA values) characterized the late Katian, which might be attributed to the global orogenesis and enhanced precipitation/runoff under the warming climate (late-Boda warming). This enhanced chemical weathering rate contributed to the CO2 drawdown in the P. pacificus biozone, corresponding to the initiation of cooling and further glaciation. Meanwhile, the enhanced weathering-induced high primary productivity could have contributed to the expansion of anoxic seawater in the Katian, which further caused the Katian extinction. The Hirnantian Glaciation was characterized by high 87Sr/86Sr ratios in carbonates and extremely low CIA values in shales, which were likely related to the exposure of continents during low sea level and the glacial grinding of unweathered rocks. This study shows that the highest denudation rate and lowest chemical weathering intensity in the Hirnantian stage might have resulted in enhanced CO2 release and contributed to the end of glaciation. [ABSTRACT FROM AUTHOR]

The Upper Ordovician (Katian) Neda Formation, a phosphatic ironstone, records a widespread but short‐lived shift to ferruginous waters across a vast epicontinental area. Lithofacies and stratigraphic reappraisal indicate that Neda ironstone deposition occurred on a storm‐dominated ramp when coastal upwelling emplaced eutrophic ferruginous waters that mixed with oxygenated surface water. This stimulated primary productivity and precipitated Fe‐(oxyhydr)oxides in the water column that formed phosphorous and iron‐rich mud. Remobilization of iron beneath the seafloor led to the syndepositional authigenic precipitation of P and Fe minerals in the sediment, preferentially coating grains and forming granular ironstone in the top few decimetres of the sediment. The top of the Neda Formation is a pronounced unconformity punctuated by laterite that formed as sea level fell during the Hirnantian Glaciation. The transition from oxygenated to ferruginous conditions that led to ironstone deposition is interpreted to have been caused by an increase in the equator‐to‐pole temperature gradient and concomitant reorganization of thermohaline circulation during the Katian. This intensified upwelling off the Laurentian margin with upwelled waters transported into the midcontinent where ironstone accumulated through the Sebree Trough. The Neda ironstone's deposition coincident with, and potentially caused by, the same drivers as global oceanographic and biotic change during the Late Ordovician both adds greater insight into the major changes in the oceans preceding the Late Ordovician Mass Extinction and Hirnantian Glaciation, and also furthers an emerging model tying ironstone deposition throughout the Phanerozoic to major Earth system events. [ABSTRACT FROM AUTHOR]

ABSTRACT A species' vulnerability to extinction is influenced by both extrinsic threats (e.g., habitat loss and invasive species) and intrinsic biological traits (such as life‐history traits, reproductive mode, and reproductive output). In this study, we investigated the roles of intrinsic biological traits in determining the risk of extinction across 960 oviparous species of non‐avian reptiles. Our findings revealed that vulnerability to extinction is negatively correlated with clutch size, but positively correlated with egg size when controlling for body size. Surprisingly, we found that body size alone is not a predictor of extinction risk. Additionally, we observed a nonsignificant relationship between the activity phase and vulnerability to extinction across oviparous species. These results suggest that the increased risk of endangerment in oviparous reptiles may stem from declining population density due to decreasing clutch size and increasing egg mass. [ABSTRACT FROM AUTHOR]

Following the end-Cretaceous mass extinction, mammals underwent an increase in body size, taxonomic diversity and ecological specialization throughout the Paleocene, exemplifying their adaptability. One especially enigmatic group is the "Triisodontidae", medium- to large-sized ungulate-like placentals from the Paleocene which are best known from their teeth that exhibit adaptations towards carnivory. The "triisodontids" were the first large carnivorous mammals and pre-date, and may have given rise to, Mesonychia, a group of more specialized placental carnivores. The "triisodontids" have been well-described from dental material, although very little is known about their postcrania. Here, we describe the postcrania of Triisodon crassicuspis–the most completely represented species of the genus to date–from a specimen (NMMNH P-72096) recovered from basal Torrejonian strata of the Nacimiento Formation in the San Juan Basin, New Mexico. Anatomical comparisons reveal that the forelimb long bones of Tri. crassicuspis are robust relative to its size, more so than other "triisodontids". Attachment sites on the ulna are evidence of well-developed muscles involved in powerful extension and flexion of the manus. In Tri. crassicuspis, the range of pronation-supination was limited as evident from the humeroradial morphology. Qualitative functional assessment of osteological features of the forelimb of Tri. crassicuspis is suggestive of terrestrial locomotion with at least moderate digging ability. Re-analyses of the dentition confirmed that Tri. crassicuspis had specializations for carnivory, and provide a body mass estimate of ca. 32–44 kg based on dental proxies. In summary, Tri. crassicuspis was a relatively large and powerful terrestrial animal, and one of the first known placentals to fill a largely carnivorous niche. [ABSTRACT FROM AUTHOR]

Liassophlebiidae is an extinct family of damsel-dragonflies found in Upper Triassic and Lower Jurassic strata of Europe, Asia and Antarctica. Whilst Liassophlebiidae is well represented by Lower Jurassic fossils, their lowest occurrence in the Upper Triassic has hitherto only been suggested by three fragmentary specimens. These were originally ascribed to two species: Liassophlebia withersi and Liassophlebia batheri, but the latter is now considered nomen dubium. Here we describe a fourth, better preserved specimen that is likely to be Rhaetian (Late Triassic) in age. The specimen, BRSMG Cg3101 a+b, was collected from Bowdens Quarry, Somerset, UK, from the lower part of the White Lias Formation. The specimen comprises an incomplete forewing attributed to Liassophlebia due to: the small number of antenodals, antesubnodals and crossveins between RP and MA based RP3/4 in the base of RP2 opposite the subnodus; a straight and elongate secondary longitudinal vein in the postdiscoidal area; numerous cells and secondary veins in radial and median areas. The specimen is likely to represent a new species and provides stronger evidence than the previous three specimens of the presence of Liassophlebiidae during the late Rhaetian. Its stratigraphical position suggests that Liassophlebiidae arose in the immediate aftermath of the Triassic-Jurassic mass extinction. [ABSTRACT FROM AUTHOR]

Analysis of a Devonian contourite depositional system in the eastern Anti-Atlas of Morocco reveals the formation of widespread erosional hiatuses and organic-rich bioclastic contourites (ORCs) coinciding with the expansion of an anoxic water mass during Frasnian bioevents, ultimately culminating in the Kellwasser crisis (Frasnian–Famennian extinction event). The identified contourite terrace formed on the uppermost slope of the northern passive margin of Gondwana. Its inner part was bounded by an alongslope contourite channel and a small mounded drift at its downslope margin. Facies- and drift-scale contourite features evidence northwest-directed bottom currents driven by repeated overflows of dense, highly saline, anoxic water originating from the northern Gondwana Epicontinental Sea. These periodic overflows were channeled through the Ougarta trough, then deflected westward over the Tafilalt contourite terrace by the Coriolis force and cascaded downslope until reaching a density equilibrium level, probably forming an intermediate water mass. The cascading of dense, anoxic shelf water supports the photic-zone eutrophication (top-down) model proposed for the Kellwasser crisis and related Devonian anoxic events. We propose a direct link between the anoxic overflows and the Devonian evolutionary events. [ABSTRACT FROM AUTHOR]

Pterocarya (Juglandaceae) is disjunctly distributed in East Asia and the Caucasus region today, but its fossils are widely distributed in the Northern Hemisphere. We first inferred phylogeny with time estimation of Pterocarya under node‐dating (ND) based on plastomes of all eight extant species and tip‐dating (TD) based on plastomes and 69 morphological characters of 19 extant and extinct species, respectively. We compared the biogeographical reconstructions on the timetrees from ND and TD, respectively, and then compiled 83 fossil records and 599 current occurrences for predicting the potential distributions for the past and the future. The most recent comment ancestor of Pterocarya is inferred in East Asia at 40.46 Ma (95% highest posterior density [HPD]: 28.04–54.86) under TD and 26.81 Ma (95% HPD: 23.03–33.12) under ND. The current distribution was attributed to one dispersal and one vicariant event without fossils, but as many as six dispersal, six vicariant, and 11 local extinction events when considering fossils. Pterocarya migrated between East Asia and North America via the Bering Land Bridge during the early Oligocene and the early Miocene periods. With the closure of Turgai Strait, Pterocarya dispersed between East Asia and Europe through the Miocene. The potential distribution analyses indicated that Pterocarya preferred warm temperate regions across the Northern Hemisphere since the Oligocene, but the drastic temperature decline caused its extinction in high latitudes. Except for Pterocarya fraxinifolia and Pterocarya stenoptera, suitable habitats for this genus are predicted to contract by 2070 due to climate change. [ABSTRACT FROM AUTHOR]

Simple Summary: The phylogenetic relationship and origin time of Phasmatodea have been discussed by many researchers. In this study, five mitogenomes of Phasmatodea were newly sequenced and the disputes about their phylogenetic relationships were explored. Additionally, five reliable fossil calibration points were used to explore the origin and diversification time of Phasmatodea. Stick and leaf insects are widely distributed in tropical and subtropical regions, with only a few species distributed at high latitudes. We collected a Phraortes liaoningensis (Phasmatodea: Lonchodidae) from Anshan City, Liaoning Province, China, to analyze whether its mitochondrial genes were under selective pressure to adapt to a low-temperature environment. Stick and leaf insects are a group among the Insecta that are famous for their extraordinary mimicry ability. Since the establishment of the Phasmatodea, their internal classification has been constantly revised. Mitochondrial genes as molecular markers have been widely used for species classification, but the phylogenetic relationships within the Phasmatodea remain to be thoroughly discussed. In the present study, five mitogenomes of Phasmatodea ranging from 15,746 bp to 16,747 bp in length were sequenced. Bayesian inference (BI) and maximum likelihood (ML) analyses were carried out based on a 13 PCGs data matrix (nt123) and a combined matrix of 13 PCGs and two rRNA genes (nt123_rRNA). The present study supports the conclusion that Phylliidae was the basal group of Neophasmatodea and confirms the monophyly of Lonchodinae and Necrosciinae, but it shows that Lonchodidae was polyphyletic. A sister group of Bacillidae and Pseudophasmatidae was also recovered. The phylogenetic tree based on the nt_123 dataset showed higher node support values. The construction of a divergent time tree in this study supported the conclusion that extant Phasmatodea originated in the Jurassic (170 Mya) and most lineages diverged after the Cretaceous–Paleogene extinction event. To explore whether the mitochondrial genes of Phraortes liaoningensis collected from high latitudes where low temperatures occur for eight months of the year are under selection pressure, this study used the branch-site model and the branch model to analyze the selection pressure on the 13 mitochondria protein-coding genes (PCGs). We found that both ND2 and ND4L of Ph. liaoningensis exhibited positive selection sites using the branch-site model. This study shows that a low-temperature environment causes mitochondrial genes to be selected to meet the energy requirements for survival. [ABSTRACT FROM AUTHOR]

Today, the most taxonomically rich bivalve clade is Imparidentia. However, 300 million years ago, Imparidentia's sister clade, Anomalodesmata, was dominant among marine bivalves, while Imparidentia was much less diverse. Both clades are ecologically diverse but infaunal suspension-feeding is the dominant mode of life in each. When taxonomic diversity and morphological disparity are plotted through time for each clade, Imparidentia diversified faster in the Mesozoic than Anomalodesmata until the K/Pg boundary, when the extinction event interrupts the pattern, and both clades then diversified in parallel through the Cenozoic. In this paper, I test the hypothesis that life mode has an effect on morphological disparification and taxonomic diversification, that by ecologically separating themselves from the dominant infaunal suspension-feeding mode, some 'divergent' anomalodesmatan lineages may have been able to free themselves from direct competition with imparidents and once more start to rise in morphological and taxonomic diversity. During the Cenozoic, morphological disparity of divergent Anomalodesmata does increase compared to their infaunal suspension-feeding relatives. However, taxonomic diversity does not differ between divergent and infaunal suspension-feeding anomalodesmatan lineages. This suggests that functional partitioning drives morphological disparification, but not taxonomic diversification. [ABSTRACT FROM AUTHOR]

With planet-wide environmental unravelling ideas of multispecies and planetary justice are gaining multidisciplinary attention. They frame a set of ethical, moral and political obligations to life-on-Earth. While it is clear it is humans who bear the duties and obligations of justice, who or what is the subject of justice-beyond-human varies widely: Some limit the subject to sentient animals, others include all living things. We argue for a more expansive subject that includes both living and non-living matter. We claim that privileging living/life is an anthropocentric categorisation embedded in the foundational epistemologies and ontologies driving environmental damages, resource conflicts and mass extinction. An exclusion of matter from concerns of justice ignores multiple fundamental more-than-human relationships in humans' every-day material lives. We argue that the subject of planetary justice must be expansive – addressing sentient or not, living or not, animal, vegetable, mineral, and elemental – to be inclusive, applied, plural, and sustainable. [ABSTRACT FROM AUTHOR]

The Neotropics are the most species-rich region on Earth, and spectacular diversification rates in plants are reported in plants, mostly occurring in oceanic archipelagos, making Neotropical and island plant lineages a model for macro-evolutionary studies. The genus Lycium in the Solanaceae family, originating from the Neotropics and exhibiting a unique disjunct geography across several islands, is therefore expected to experience exceptional diversification events. In this study, we aimed to quantify the diversification trajectories of the genus Lycium to elucidate the diversification events within the genus. We compiled a DNA matrix of six markers on 75% of all the species in the genus to reconstruct a dated phylogeny. Based on this phylogeny, we first revisited the historical biogeography of the genus. Then, we fitted a Compound Poisson Process on Mass Extinction Time model to investigate the following key evolutionary events: speciation rate, extinction rate, as well as mass extinction events. Our analysis confirmed that South America is the origin of the genus, which may have undergone a suite of successive long-distance dispersals. Also, we found that most species arose as recently as 5 million years ago, and that the diversification rate found is among the slowest rates in the plant kingdom. This is likely shaped by the multiple speciation and extinction rate shifts that we also detected throughout the evolutionary history of the genus, including one mass extinction at the early stage of its evolutionary history. However, both speciation and extinction rates remain roughly constant over time, leading to a gradual species accumulation over time. [ABSTRACT FROM AUTHOR]

The Mississippian was an epoch of strong earth system changes, both tectonic and climatic. During the Mississippian, the marine faunas experienced a recovery after the late Devonian mass extinctions, and the rugose corals are a conspicuous example. This study tries to give a general view of the utility of rugose coral to reconstruct the palaeogeography in the Western Palaeotethys during the Mississippian. The methodology includes a database with the genera and species recorded in that area and time period, compiled using more than 700 articles and revisions of several collections in Europe. We worked with the six sub-provinces defined in previous studies for the Western Palaeotethys. A generic-level analysis was performed using paired group hierarchical clustering, building clusters for the Tournaisian, early Visean, late Visean and Serpukhovian. With that information, palaeomaps for those intervals have been illustrated and discussed. The rugose corals have some deficits for the reconstruction of the biogeography because of their strong palaeoecologic control and their insufficient and unequal record, but they provide important information that improves the knowledge on the palaeogeography of the studied region. [ABSTRACT FROM AUTHOR]

A recent article by DePalma et al. reported that the season of the End-Cretaceous mass extinction was confined to spring/summer on the basis of stable isotope analyses and supplementary observations. An independent study that was concurrently under review reached a similar conclusion using osteohistology and stable isotope analyses. We identified anomalies surrounding the stable isotope analyses reported by DePalma et al. Primary data are not provided, the laboratory where the analyses were performed is not identified, and the methods are insufficiently specified to enable accurate replication. Furthermore, isotopic graphs for carbon and oxygen contain irregularities such as missing data points, duplicate data points, and identical-length error bars for both elements despite different scales, that appear inconsistent with laboratory instrument outputs. A close examination of such methodological omissions and data irregularities can help to raise the standards for future studies of seasonality and prevent inaccurate claims or confirmation bias. [ABSTRACT FROM AUTHOR]

Managerial cognition research is becoming more prevalent in the corporate sustainability literature, providing insights as to how functioning of the mind impacts decision‐making. As we witness catastrophic decline of the planet's natural capital, entering the sixth wave of mass extinction, this study investigates decision‐making related to natural resource consumption through interviews with 32 decision‐makers in the construction/infrastructure and manufacturing industries. Drawing on mindset theory and interview data, we develop the concept of an operational mindset and a societal mindset. The study also identifies the occurrence of individuals switching between operational and societal mindsets when asked to consider the sustainability of key natural resources for the interviewees' organisations. While similarities exist with the prominent business case and paradoxical cognitive frames concept, a number of differences are identified by drawing on the foundations of mindset theory and extensive empirical research from its application in other business disciplines. [ABSTRACT FROM AUTHOR]

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Sagenopteris is the most common fossil organ attributed to Caytoniales and is represented by compound leaves having several (usually four) lanceolate leaflets in pseudo‐palmate arrangement. Since Presl's description of Sagenopteris in 1838, at least 82 species have been identified worldwide. However, most were established on a few isolated leaflets without sufficient details for confident segregation from other forms. After a global evaluation of the character states, nomenclature and taxonomic validity of all described Sagenopteris species, only five can be retained as nomenclaturally valid and morphologically distinct: Sagenopteris acuminata (lectotype species), S. colpodes, S. hallei, S. phillipsii and S. pualensis. Comprehensive assessment of Sagenopteris foliage based on historical studies and institutional collections shows a high degree of morphological plasticity within individual leaf populations. Multivariate plots of key leaf characters show broad morphotypes within populations that, if selectively sampled, might readily result in the recognition of multiple fossil‐species. Cuticular features are more stable for species‐level differentiation. Temporo‐spatial analysis of Sagenopteris suggests it originated in the European (palaeo‐subtropical) region by the Anisian (Middle Triassic) and underwent significant range expansion during the Late Triassic. Surviving the end‐Triassic mass extinction, Sagenopteris quickly became one of the dominant gymnosperms in the aftermath of the biotic crisis, reaching its peak abundance during the Early and Middle Jurassic. This taxon began to decline in floristic importance from the Late Jurassic to Late Cretaceous. The youngest occurrences of Sagenopteris, globally, are from Cenomanian–Campanian assemblages of middle to high northern latitudes. No examples are known from the Cenozoic. [ABSTRACT FROM AUTHOR]

Fissure fill deposits from the Late Triassic to Early Jurassic of England and Wales preserve a diverse small tetrapod fauna including procolophonids, an important group of Permian and Triassic parareptiles that radiated across Pangaea following the end‐Permian extinction event. Procolophonids are currently known from two fissure fill sites: incomplete and isolated remains from Ruthin Quarry (Wales) and type and referred material of Hwiccewyrm trispiculum from Cromhall Quarry (southwest England). The age of the Cromhall fissure deposits has been debated but recent radiometric dating suggests a Carnian age for at least some of the fossil assemblages. Here, we present material from several fissure assemblages at Cromhall, which are interpreted as stratigraphically older than the assemblage that yielded Hwiccewyrm. We describe a new species of leptopleuronine procolophonid based on partial remains with unique tooth morphology. Threordatoth chasmatos gen. et sp. nov. is characterized by maxillae with a reduced number of complex tricuspid teeth along with dentaries that bear labiolingually compressed monocuspid teeth and in some cases have a peculiar edentulous tip. These distinct tooth morphologies occlude closely, perhaps facilitated by a flexible dentary symphyseal connection. This unique combination of characters may suggest a high degree of oral food processing of a mode unlike other procolophonids, occurring among the broader leptopleuronine adaptation towards diets of high‐fibre herbivory/omnivory and insectivory. Phylogenetic analysis places the remains of Threordatoth as a derived leptopleuronine, sister taxon to Hwiccewyrm, in a clade with taxa including Soturnia, Hypsognathus, Libognathus and two unnamed leptopleuronines from the southwest USA. [ABSTRACT FROM AUTHOR]

The long-term effects of the Central Atlantic Magmatic Province, a large igneous province connected to the end-Triassic mass-extinction (201.5 Ma), remain largely elusive. Here, we document the persistence of volcanic-induced mercury (Hg) pollution and its effects on the biosphere for ~1.3 million years after the extinction event. In sediments recovered in Germany (Schandelah-1 core), we record not only high abundances of malformed fern spores at the Triassic-Jurassic boundary, but also during the lower Jurassic Hettangian, indicating repeated vegetation disturbance and stress that was eccentricity-forced. Crucially, these abundances correspond to increases in sedimentary Hg-concentrations. Hg-isotope ratios (δ202Hg, Δ199Hg) suggest a volcanic source of Hg-enrichment at the Triassic-Jurassic boundary but a terrestrial source for the early Jurassic peaks. We conclude that volcanically injected Hg across the extinction was repeatedly remobilized from coastal wetlands and hinterland areas during eccentricity-forced phases of severe hydrological upheaval and erosion, focusing Hg-pollution in the Central European Basin. This study provides evidence for long-term effects of volcanic emissions of large quantities of gaseous mercury (Hg) and plant mutagenesis by recording high abundances of malformed fern spores across the Triassic-Jurassic boundary and Early Jurassic. [ABSTRACT FROM AUTHOR]

We are living in an era of environmental change with undeniable parallels with past mass extinctions. To improve our understanding of planetary health and resilience, we must expand our research beyond traditional lab models. Forecasting the future of biological diversity relies on extrapolation of past trends, which necessitates the study of a wider range of biological systems. The 'Unconventional and Emerging Experimental Organisms for Cell and Developmental Biology' meeting, which took place in Dorking, UK, in September 2023, emphasized the importance of this broader approach. Discussions centered on evolutionary innovation, robustness and diversity, underscoring the need for broader taxon sampling and novel experimental models to address current and future challenges. [ABSTRACT FROM AUTHOR]

Allokotosauria (Trilophosauridae + Azendohsauridae) is a clade of Early – Late Triassic quadruped, sprawling archosauromorphs with diverse dietary habits, known from Madagascar, India, Morocco, North America, and Europe. We conducted the first quantitative biogeographic analysis of the clade to reconstruct its ancestral areas and dispersal events. The results estimated the India + Tanzania area as ancestral for Allokotosauria. Eastern North America was reconstructed as the ancestral area of Trilophosauridae, implying an Early Triassic Southern to Northern Hemisphere dispersal. Subsequently, trilophosaurids were restricted to the Northern Hemisphere, and at least two dispersal events from Europe to western North America are estimated during the early Anisian and probably during the early Carnian, respectively. Azendohsauridae retained the ancestral area of India + Tanzania during much of its evolutionary history. Two dispersal events to western and eastern North America, respectively, are reconstructed during the Carnian – early Norian, likely during or in the aftermath of the Carnian Pluvial Episode (CPE). This pattern mirrors that of early dinosaurs, which were restricted to the Southern Hemisphere with dispersals to the Northern Hemisphere not recorded until the end of the CPE. This study informs about biogeographic patterns involved in the biotic recovery after the end-Permian mass extinction and the early evolutionary radiation of Archosauromorpha. [ABSTRACT FROM AUTHOR]

Fungus-farming ants cultivate multiple lineages of fungi for food, but, because fungal cultivar relationships are largely unresolved, the history of fungus-ant coevolution remains poorly known. We designed probes targeting >2000 gene regions to generate a dated evolutionary tree for 475 fungi and combined it with a similarly generated tree for 276 ants. We found that fungus-ant agriculture originated ~66 million years ago when the end-of-Cretaceous asteroid impact temporarily interrupted photosynthesis, causing global mass extinctions but favoring the proliferation of fungi. Subsequently, ~27 million years ago, one ancestral fungal cultivar population became domesticated, i.e., obligately mutualistic, when seasonally dry habitats expanded in South America, likely isolating the cultivar population from its free-living, wet forest-dwelling conspecifics. By revealing these and other major transitions in fungus-ant coevolution, our results clarify the historical processes that shaped a model system for nonhuman agriculture. [ABSTRACT FROM AUTHOR]

Burrowed discontinuity surfaces associated with condensed fossil concentrations demarcate breaks (hiatuses) in the Phanerozoic marine sedimentary record. Such intervals may be difficult to interpret in view of complex anatomy and varied fossil signatures. Transformation of a discontinuity surface into a heavily burrowed 'pseudobreccia' may further complicate the record, but this issue has remained unexploited to date. The richly fossiliferous Cretaceous–Paleogene (Maastrichtian–Danian) boundary interval exposed in Poland provides opportunities to test the influence of burrow-generated pseudobreccia on the preservation of associated hiatal fossil concentrations. Here, we document pseudobreccia anatomy and fossil-sediment relationships by three-dimensional X-ray computed tomography imaging. In the pseudobreccia zone, we identify a distinctive assemblage of late Maastrichtian fossils, which underwent subsurface preparation by burrowers in a hitherto unreported ichno-taphonomic process. Recognition of pseudobreccia is a prerequisite for the interpretation of the stratigraphy, sedimentology and fossil record of such intervals, which is of special interest for periods of major biotic turnovers, like the end-Cretaceous mass extinction. [ABSTRACT FROM AUTHOR]

Mass extinctions are considered to be quintessential examples of Court Jester drivers of macroevolution, whereby abiotic pressures drive a suite of extinctions leading to huge ecosystem changes across geological timescales. Most research on mass extinctions ignores species interactions and community structure, limiting inference about which and why species go extinct, and how Red Queen processes that link speciation to extinction rates affect the subsequent recovery of biodiversity, structure and function. Here, we apply network reconstruction, secondary extinction modelling and community structure analysis to the Early Toarcian (Lower Jurassic; 183 Ma) Extinction Event and recovery. We find that primary extinctions targeted towards infaunal guilds, which caused secondary extinction cascades to higher trophic levels, reproduce the empirical post-extinction community most accurately. We find that the extinction event caused a switch from a diverse community with high levels of functional redundancy to a less diverse, more densely connected community of generalists. Recovery was characterised by a return to pre-extinction levels of some elements of community structure and function prior to the recovery of biodiversity. Full ecosystem recovery took ~7 million years at which point we see evidence of dramatically increased vertical structure linked to the Mesozoic Marine Revolution and modern marine ecosystem structure. Mass extinctions have repeatedly restructured communities through geological time, but biotic interactions are rarely considered in investigations of extinction dynamics and ecosystem recovery. Here the authors present evidence that secondary extinction cascades were important during a Jurassic hyperthermal extinction event and that it took over 7 million years for community structure to fully recover. [ABSTRACT FROM AUTHOR]

Zygaenidae, also known as burnet, forester, smoky, or leaf skeletonizer moths, are a family of mainly diurnal moths well known for their aposematic colouration and the ability to release hydrogen cyanide as a defence mechanism. So far, few attempts have been made to understand the evolutionary history of the global zygaenid fauna. Here, we inferred the most comprehensive molecular phylogeny for Zygaenidae to date and estimated the lineage timing‐of‐divergence with a Bayesian approach. Building on earlier work, we significantly increased the taxon and gene sampling for the family, which here included data from 30 gene fragments, recovered from public databases or newly sequenced, for almost 30% of the species representing 92 genera (49%) and all five subfamilies. We recovered strong support for the monophyly of Zygaenidae, Chalcosiinae, and Zygaeninae. Procridinae were recovered as monophyletic with low support, whereas the monophyly of Callizygaeninae remains untested as we sampled only one of the two genera. In the core dataset, we recovered Procridinae as sister to Callizygaeninae + Chalcosiinae. This large clade is the sister lineage to Zygaeninae. The position of Inouelinae could not be resolved. The lineage leading to the extant Zygaenidae appears to have diverged in Late Cretaceous (ca. 86 Ma), while the divergence among the subfamilies occurred several million years before the Cretaceous–Paleogene mass extinction event (ca. 66 Ma). Additionally, we provide a review of known fossil Zygaenidae as Appendix S1. Our results form a strong basis for future studies of zygaenid biosystematics, including their ecology, evolution, and behaviour. [ABSTRACT FROM AUTHOR]

Temnospondyli appeared in the early Carboniferous, became extinct in the Early Cretaceous and reached high diversity especially during the Permian and Triassic. After the end-Permian mass extinction, almost only Stereospondyli survived (with the exception of the dissorophoid Micropholis). This clade radiated and gave rise to several successful groups: Plagiosauroidea, Trematosauroidea, Metoposauroidea, Capitosauria, and Brachyopoidea. While Brachyopoidea survived into the Early Cretaceous, the other groups were thought to have gradually disappeared during the Late Triassic, going extinct before the Rhaetian. This hypothesis was supported by the lack of unambiguously dated Rhaetian localities with Stereospondyli fossils. This gap was filled by the discovery of the Bonenburg clay pit in North Rhine-Westphalia (Germany). This locality has been unequivocally dated to the late middle Rhaetian and had yielded a temnospondyl fossil assigned to Capitosauria. Here we describe further Stereospondyli fossils from Bonenburg, including diagnostic bones such as a dentary, a pterygoid, a parietal, and eight other bones in different states of preservation. These fossils belong to at least two taxa of Capitosauria and one taxon of Plagiosauridae and represent the geologically youngest remains of both clades. The specimens are described morphologically, and for the long bones, a clavicle fragment, and an unidentified dermal bone, histological analysis was used to further confirm the morphological analysis. These results shed light on the extinction of two major groups of Stereospondyli, documenting that some non-brachyopoid temnospondyls survived until the end of the Triassic. [ABSTRACT FROM AUTHOR]

Scientific evidence has documented we are undergoing a mass extinction of species, caused by human activity. However, allocating conservation resources is difficult due to scarce evidence on damages from losing individual species. This paper studies the collapse of vultures in India, triggered by the expiry of a patent on a painkiller. Our results suggest the functional extinction of vultures—efficient scavengers that removed carcasses from the environment—increased human mortality by over 4 percent because of a large negative shock to sanitation. We quantify damages at $69.4 billion per year. These results suggest high returns to conserving keystone species such as vultures. (JEL I12, O13, O15, Q53, Q57, Q58) [ABSTRACT FROM AUTHOR]

Ocean anoxia is considered a key driver of the end‐Permian mass extinction (EPME). However, it is much debated whether there was an ocean reoxygenation phase during, and in the aftermath, of the EPME. Evidence for ocean reoxygenation is often inferred from the absence of framboidal pyrite in some boundary marine sediments (termed the "framboid gap"). To reconstruct ocean redox evolution across the EPME, we investigated the carbon isotopic, sedimentological, and redox records of the Ruichang and Ehtan sections in South China. These documents two negative δ13Ccarb excursions and the development of anoxia associated with deepening leading up to the Permian‐Triassic boundary. Above the level at which most siliceous organisms became extinct, pyrite framboid and iron proxies indicate that water column redox conditions were predominantly oxygenated but sporadically anoxic/ferruginous [non‐sulfidic, free Fe(II) in the water] at Ruichang, while ferruginous conditions were more widely developed at Ehtan. These contrasting redox states are characteristic of a dynamic ocean redox landscape in the extinction interval. The "framboid gap" is seen in strata deposited under both oxic and ferruginous conditions, suggesting that the availability of decomposable organic matter for sulfate reduction additionally controlled framboid genesis. Our data confirm that oxygenated conditions were developed in some deep water basins during the EPME. Plain Language Summary: Ocean oxygen levels across the Permian‐Triassic boundary, which saw Earth's greatest mass extinction (the End Permian Mass Extinction; EPME) have long been debated. Oxygen‐poor (anoxic) conditions are widely implicated in the EPME. A gap in the record of pyrite framboids (small aggregates of pyrite that are commonly found in sedimentary rocks that were deposited in oxygen‐poor marine environments) in some settings during the EPME is generally considered to be a function of reoxygenation at that time. We analyzed iron phase partitioning proxies (which can reveal ocean oxygen levels at the time of deposition) from two chert‐bearing sections in South China. Our iron data indicate that the "framboid gap" is manifest in marine sedimentary archives that were not only well oxygenated at the time of deposition but also anoxic and ferruginous (non‐sulfidic, free Fe(II) in the water). This highlights the ambiguity of the "framboid gap" in implying oxygenated conditions as well as the heterogeneous spatial nature of ocean oxygen states during the EPME. Key Points: Water column reoxygenation during the end‐Permian mass extinction (EPME) is controversialRedox proxies reveal large redox heterogeneity, with deep waters experiencing oxygenated conditions during the extinction intervalBoth ocean reoxygenation and the development of ferruginous conditions contributed to the Lower Triassic pyrite framboid gap [ABSTRACT FROM AUTHOR]

In the wake of the greatest mass extinction in Earth's history, the End-Permian Mass Extinction, the Triassic was a time of recovery and innovation. Aided by warm climatic conditions and favorable ecological circumstances, many reptilian clades originated and rapidly diversified during this time. This set the stage for numerous independent invasions of the marine realm by several reptilian clades, such as Ichthyosauriformes and Sauropterygia, shaping the oceanic ecosystems for the entire Mesozoic. Although comparatively less speciose, and temporally and latitudinally more restricted, another marine reptile clade, the Thalattosauriformes, stands out because of their unusual and highly disparate cranial, dental and skeletal morphology. Research on Thalattosauriformes has been hampered by a historic dearth of material, with the exception of rare material from Lagerstätten and highly fossiliferous localities, such as that from the UNESCO world heritage site of Monte San Giorgio. Consequently, their evolutionary origins and paleobiology remain poorly understood. The recent influx of new material from southwestern China and North America has renewed interest in this enigmatic group prompting the need for a detailed review of historic work and current views. The earliest representatives of the group may have been present from the late Early Triassic onwards in British Columbia. By the Ladinian the group had achieved a wide distribution across the northern hemisphere, spanning the eastern Panthalassic as well as the eastern and western Tethyan provinces. Distinct morphological and likely ecological differences exist between the two major clades of Thalattosauriformes, the Askeptosauroidea and the Thalattosauroidea, with the latter showing a higher degree of cranial and skeletal morphological disparity. In-group relationships remain poorly resolved beyond this bipartition. Overall, thalattosaurs may be closely related to other marine reptile groups such as ichthyopterygians and sauropterygians. However, their exact position within Diapsida remains elusive. Future focal points should utilize modern digital paleontological approaches to explore the many fragmentary specimens of otherwise poorly sampled localities. [ABSTRACT FROM AUTHOR]

The ultimate driver of the end-Permian mass extinction is a topic of much debate. Here, we used a multiproxy and paleoclimate modeling approach to establish a unifying theory elucidating the heightened susceptibility of the Pangean world to the prolonged and intensified El Niño events leading to an extinction state. As atmospheric partial pressure of carbon dioxide doubled from about 410 to about 860 ppm (parts per million) in the latest Permian, the meridional overturning circulation collapsed, the Hadley cell contracted, and El Niños intensified. The resultant deforestation, reef demise, and plankton crisis marked the start of a cascading environmental disaster. Reduced carbon sequestration initiated positive feedback, producing a warmer hothouse and, consequently, stronger El Niños. The compounding effects of elevated climate variability and mean state warming led to catastrophic but diachronous terrestrial and marine losses. [ABSTRACT FROM AUTHOR]

For the philosopher Timothy Morton, the origin of religion has been narrated as the beginning of agricultural time, an origin in sin. Before the fall, there was no scarcity in the garden. Cursed was the ground as punishment for original sin, and there was no possibility of return: Cherubims and a flaming sword which turned every way were placed at the east of Eden (Gen. 3.24). Such a curse would instill a fear of barren land, of famine, of futile labor. The solution would eventually become monocropping and industrial farming that threaten to cause mass extinction. But how can industrial agriculture fail to produce more food? How can the solution be the new problem? These reflections and questions will explore (com)promised lands in two Latin American novels now lost to the canon —Ramón Amaya Amador's Prisión verde (1945), and Ernesto L. Castro's Campo arado (1953)—, as well as in the classic and very canonical Doña Bárbara (1929) by Romulo Gallegos, and in an Iberian television series, Mar de plástico (2015-2016) that also calls attention to toxic, lawless farming. The intention is not so much to provide answers here for the open questions, but rather to think through the knots, the tangles, the interactions. This paper is an effort to go beyond dualistic representational systems such as farmer-herder, Cain-Abel, nature-culture, industrial-organic, lawless-law-abiding, heedful-unwary, carnivore-vegetarian. [ABSTRACT FROM AUTHOR]

Anticosti Island (Québec, Canada) contains one of the thickest Ordovician/Silurian boundary sections in the world, providing a fossiliferous and well-preserved record of the Late Ordovician mass extinction; however, the absence of a comprehensive correlation framework for the island prevents the full incorporation of data from across Anticosti into a global understanding of the extinction event. Here, we combine sedimentological, stratigraphic, and chemostratigraphic data to develop a sequence stratigraphic framework for the Ellis Bay and lowermost Becscie formations along the northeastern shore of Anticosti Island. These formations record six fourth-order (∼100–400 k.y.) depositional sequences bounded by regionally traceable unconformities. Evidence of subaerial weathering and exposure at many of these unconformities is subtle and has long gone unrecognized, which highlights the complexity of correlation in this and other stratigraphically thin icehouse records. Quartz pebble lags that mantle these surfaces punctuate the otherwise fine-grained, mixed carbonate–siliciclastic strata of the Ellis Bay Formation and provide the means to trace unconformities across localities; these surfaces are also marked by depleted carbon isotopic values, meteoric cement, microkarst, and incised valleys. This sequence stratigraphic framework provides the first correlation framework for exposures from the eastern end of this classic Ordovician/Silurian boundary section, and thus enables the integration of paleobiological, stratigraphic, and geochemical data into a basin-wide perspective of the Late Ordovician mass extinction. Critically, comparison to sequence stratigraphic frameworks from coeval sections suggests that other regions may be incomplete at the level of the fourthorder cycles recorded on Anticosti Island and may contain similarly cryptic unconformities. [ABSTRACT FROM AUTHOR]