Mass Extinction Research Articles

Terrestrial evidence for volcanogenic sulfate-driven cooling event ~30 kyr before the Cretaceous-Paleogene mass extinction.

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.

First discovery of actinopterygian cutting-edged teeth from the middle Norian (Late Triassic) at the Tulong section, southern Tibet, China

Actinopterygians (ray-finned fishes) successfully passed through the Permian-Triassic Mass Extinction (PTME) and flourished in the Triassic with diverse feeding specializations and occupation of various trophic levels. Birgeria, one of the largest actinopterygian fish of the Triassic, was characterized by a strong, blunt rostrum and three rows of sharp cutting-edged teeth, making them the top predators in the Early Mesozoic oceanic ecosystem. These fishes rapidly radiated and diversified globally during the Early and Middle Triassic, but the fossil record is rare for the Neo-Tethys in the Late Triassic. Here, we report new actinopterygian teeth with cutting edges from Norian-age strata in the Tulong section, which was located on the northern margin of the Indian Plate at that time. The tooth features, such as the polished acrodin cap, the ratio of the acrodin cap in length, and the tiny vertical striae at the tooth base, suggest an affinity with Birgeria, which is reported in this region for the first time. Furthermore, we infer that the carnivorous Birgeria, which co-occurred with the enigmatic ichthyosaur Himalayasaurus tibetensis, played the role of predator in this part of the Neo-Tethys marine realm during the Late Triassic. These new findings increase the known diversity of actinopterygians during the Late Triassic and provide further insight into the marine fauna of this epoch.

Pseudosuchia: Masters of survival and diversification.

In the context of an increasing interest for Pseudosuchia, we have compiled a Special Issue, comprising 14 collaborative studies that deepen our understanding of pseudosuchian evolution. These contributions range from the description of a new taxon to exhaustive reviews of thermometabolism, morphological adaptation, systematics, and detailed investigations into ontogeny, paleoneurology, paleohistology, and paleobiology. Through these papers, we explore the evolutionary history of pseudosuchian archosaurs, spotlighting their rise and diversification following the end-Permian mass extinction.

Chitinozoan biostratigraphy through the Aeronian–Telychian boundary interval on Anticosti Island, Canada

Abstract. The well-preserved Llandovery (lower Silurian) succession of Anticosti Island (Quebec, eastern Canada) contains an expanded Aeronian–Telychian boundary interval when compared to other coeval basins. This boundary interval on Anticosti Island also includes two of the most important Llandovery biogeochemical events, the late Aeronian and Valgu events. These two events were previously documented in the Jupiter and Chicotte formations through the study of conodont, graptolite, and brachiopod biostratigraphy and δ13C chemostratigraphy. Despite these multiple investigations, the exact position of the Aeronian–Telychian stage boundary on Anticosti Island has not been firmly established. Here we locally define and globally correlate chitinozoan biozones to refine the position of this stage boundary. The Ancyrochitina ramosaspina biozone, recognized in the Ferrum Member of the Jupiter Formation, correlates with the global Conochitina alargada biozone and indicates an Aeronian age. The Eisenackitina dolioliformis biozone suggests mostly a Telychian age for the Pavillon Member of the Jupiter Formation and the Chicotte Formation. Three new species are defined, namely Conochitina asselinae sp. nov., Spinachitina glooscapi sp. nov., and Ancyrochitina wilsonae sp. nov. (registration date: 4 December 2024, publication LSID: urn:lsid:zoobank.org:pub:11184506-F273-4D7A-BC28-A1BB4BC8FCD8, asselinae LSID: D282DA9D-6A9C-4B9E-AA6C-9ADC4473E95B, glooscapi LSID: 5801DC12-4EA1-439F-B7C8-FAF7C1B9D2C7, wilsonae LSID: 549EEF2F-7F19-4E6D-9F8E-384594B2FE65). Our new chitinozoan data, combined with previous studies, allow a comparison with the well-studied Baltic succession, confirming that limited unconformities mark the Aeronian–Telychian boundary interval on Anticosti Island, in contrast to the less complete coeval location. Our refined age model for the Aeronian to Telychian succession of Anticosti Island provides a solid baseline to study further Llandovery biochemical events in the aftermath of the Late Ordovician mass extinction.

The Milky Way as seen by classical Cepheids II: Spiral structure

As a relatively young and bright population and the archetype of standard candles, classical Cepheids are an ideal population on which to trace the non-axisymmetric structure in the young stellar disk to large distances. We used the new distances derived in Paper I based on mid-IR WISE photometry for a selected sample of 2857 dynamically young Cepheids to trace the spiral arms of the Milky Way. The Perseus and Sagittarius-Carina arms are clearly evident in the third and fourth Galactic quadrants, while the Local and Scutum arms are much weaker, and extinction severely limits our view of the latter innermost spiral arm. Pitch angles were derived for each arm over various ranges of Galactic azimuth, each covering at least 90 in azimuth. Our method of detecting spiral arms and deriving pitch angles does not rely on pre-assigning sources to specific arms. While the spiral structure in the first and second quadrant is not obvious in part because of extinction effects, it is not inconsistent with the structure seen in the third and fourth quadrants. In summary, the Cepheids allow us to map spiral structure in the third and fourth Galactic quadrants where currently few masers have astrometric parallaxes, significantly extending our understanding of the Milky Way at large scales.

Rapid pyrolysis of paleo-oil pools recorded by fluid inclusions in an Ediacaran carbonate reservoir, southern China: Implications for the end-Guadalupian mass extinction

Thermogenic greenhouse gas emission associated with large igneous province emplacement has previously been hypothesized as a possible contributor to global warming that triggered mass extinctions in Earth’s history, yet this issue remains inadequately understood due to a lack of robust evidence. We present a well-preserved mineralogical, fluid inclusion, and geochemical record indicating a rapid pyrolysis of vast paleo-oil pools in an Ediacaran carbonate reservoir in the central Sichuan Basin (southern China) relating to the eruption of the Emeishan large igneous province that potentially contributed to the end-Guadalupian extinction (ca. 259 Ma). We conclude that the pyrolysis of the paleo-oil pools occurred at ca. 258.4 ± 7.3 Ma associated with the emplacement of the Emeishan large igneous province, causing a rapid increase of temperature and pressure with an estimated transient reservoir pressure of nearly twice that of the lithostatic pressure. A subsequent drop in the formation pressure occurred as the temperature continued to rise, indicating that massive over-pressured methane in the reservoir had been rapidly emitted into the atmosphere along faults or magmatic pipes, ultimately contributing to the end-Guadalupian extinction. Our study highlights the significance of massive emission of thermogenic methane related to large igneous provinces for climate change, carbon cycling, and biological evolution in Earth’s history.

A Sixth Mass Extinction? How Linguistic Uncertainty Shapes Our Understanding of the Biodiversity Crisis.

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.

Arthropod Food Webs in the Foreland of a Retreating Greenland Glacier: Integrating Molecular Gut Content Analysis With Structural Equation Modelling.

The Arctic has warmed nearly four times faster than the global average since 1979, resulting in rapid glacier retreat and exposing new glacier forelands. These forelands offer unique experimental settings to explore how global warming impacts ecosystems, particularly for highly climate-sensitive arthropods. Understanding these impacts can help anticipate future biodiversity and ecosystem changes under ongoing warming scenarios. In this study, we integrate data on arthropod diversity from DNA gut content analysis-offering insight into predator diets-with quantitative measures of arthropod activity-density at a Greenland glacier foreland using Structural Equation Modelling (SEM). Our SEM analysis reveals both bottom-up and top-down controlled food chains. Bottom-up control, linked to sit-and-wait predator behavior, was prominent for spider and harvestman populations, while top-down control, associated with active search behavior, was key for ground beetle populations. Bottom-up controlled dynamics predominated during the early stages of vegetation succession, while top-down mechanisms dominated in later successional stages further from the glacier, driven largely by increasing temperatures. In advanced successional stages, top-down cascades intensify intraguild predation (IGP) among arthropod predators. This is especially evident in the linyphiid spider Collinsia holmgreni, whose diet included other linyphiid and lycosid spiders, reflecting high IGP. The IGP ratio in C. holmgreni negatively correlated with the activity-density of ground-dwelling prey, likely contributing to the local decline and possible extinction of this cold-adapted species in warmer, late-succession habitats where lycosid spiders dominate. These findings suggest that sustained warming and associated shifts in food web dynamics could lead to the loss of cold-adapted species, while brief warm events may temporarily impact populations without lasting extinction effects.

Pseudoconocardium licharewi Zavodowsky, 1960, the latest representative of the extinct class Rostroconchia (Mollusca)

Rostroconchs are one of the “minor classes” of the phylum Mollusca. They were especially diverse in Early and Middle Palaeozoic, but by the end of Late Palaeozoic the group’s diversity had sharply declined. This study shows that rostroconchs completely disappeared from the fossil record before the great end-Permian mass extinction event. The paper offers the first review of all Permian rostroconch localities in Northeast Russia and discusses their possible depositional settings. All records are precisely referenced to the zonal bivalve scale of Northeast Asia, calibrated and correlated with the International Chronostratigraphic Chart using SHRIMP and ID-TIMS dating, taking into account δ13Corg chemostratigraphic data. All Permian rostroconchs in this region are represented by different forms of preservation of the same species — Pseudoconocardium licharewi Zavodowsky, 1960 and are distributed in the interval: the second half of the Artinskian — the lower part of the Changhsingian. Thus, the species in question is the latest known representative of rostroconch in the world. The type series of Pseudoconocardium licharewi, type species of the genus Pseudoconocardium Zavodowsky, 1960, as well as specimens housed in the collection of the Borissiak Paleontological Institute of the Russian Academy of Sciences, are examined. Based on a detailed study of shell morphology, an emended generic diagnosis and a new description are presented here. It is also shown that the genus Pseudoconocardium is monotypic.

Calcium isotopes support spatial redox gradients on the Tethys European margin across the Triassic-Jurassic boundary

The end-Triassic mass extinction was among the most severe biotic crises of the Phanerozoic. It has been linked with the global expansion of marine anoxia, and the prolongation of these conditions within epeiric seas has been proposed as a cause for the suppression of biodiversity during the Hettangian. Testing this interpretation is complicated by spatially heterogeneous patterns of local marine redox conditions within the western Tethys European Epicontinental Shelf. In this study, we assess the redox state within this region by focusing on two carbonate successions in Italy, a peritidal platform at Mount Sparagio, Sicily, and an offshore ramp deposit at Val Adrara in the Southern Alps. Based on previously published I/Ca ratios, these locations record distinct local background redox conditions, with Val Adrara showing a notably lower pre-extinction oxygen saturation state than Mount Sparagio. Here, we measure δ13C and δ18O at Mount Sparagio and δ44Ca and trace element ratios at both sites to identify the roles of mineralogical and diagenetic effects on the preservation of primary redox signals. A numerical framework of multiple elemental (Sr, Mg, Mn, I) and isotopic (δ13C, δ18O, δ44Ca, δ238U, and δ34SCAS) ratios was constructed to recognize modes of carbonate diagenesis and source-mixing in the data. While diagenesis is impossible to completely rule out, our state-of-the-art approach provides robust evidence against common forms of diagenetic alteration as the main drivers of the overall paleoredox proxy trends.Where the redox signals are largely preserved, we interpret differences in pre-extinction I/Ca between the two sites to reflect distinct local oxygenation states. Drawing from published Community Earth System Model simulations, we propose that ocean circulation and hydrological regime could have been important drivers of spatial heterogeneity in paleo-redox conditions across the European Epicontinental Shelf.

Unveiling Biodiversity: The current status of marine species barcoding in Red Sea Metazoans

Preserving biodiversity is a global challenge. Censuses of marine biodiversity are indispensable for monitoring the responses of marine life to environmental changes induced by human activities. Ongoing extinction events affect both species and populations amid unprecedented environmental changes induced by climate shifts and habitat degradation. These changes result in substantial declines in biodiversity. In addition, our understanding of oceanic life remains incomplete, especially regarding elusive, rare, delicate, or understudied organisms. One example for this is the biodiversity of the Red Sea which remains largely unexplored and poorly understood. In an attempt to evaluate the current status of known versus COI-barcoded marine animal species in the Red Sea we used online taxonomic and genetic databases to provide a comprehensive analysis of the region's described marine life, focusing on the occurrence data of marine animal species to identify disparities in COI barcoding coverage at the phylum level. Our analysis reveals that barcoding coverage varies significantly among phyla, with Nematoda, Platyhelminthes, Bryozoa, and Porifera being highly underrepresented compared to Chordata. While over 6,000 metazoan species from 22 phyla are known to inhabit the Red Sea, only 49.77% appear to be barcoded. COI barcoding helps preserve biodiversity by providing a reliable and standardized method for accurately identifying and monitoring species, including those that are cryptic or newly discovered, thereby informing and enhancing conservation efforts and guiding future research efforts toward understudied regions and organisms.

Surviving the Tide: Assessing Guiana dolphin persistence amidst growing threats in a protected estuary in South-eastern Brazil

This study investigated the population viability of Sotalia guianensis in the Cananéia Estuarine-Lagoon Complex, considering current and potential future scenarios. Simulations, using VORTEX software v. 10.5.5.0, spanned 100 years and were iterated 1000 times. Scenarios encompassed adjustments to demographic and environmental factors, evaluating population trajectories (baseline; increase fisheries; increase tourism; and increase harbour activity scenarios). Findings revealed a potential stochastic growth rate and population stabilization in baseline and increase tourism scenarios when major threats were absent. Conversely, increase fishing and harbour activity scenarios exhibited population decline, leading to eventual extinction within 100 years. Projected growth rates for all Scenarios were 0.0298 (SD=0.0424), −0.2650 (SD=0.2825), 0.0294 (SD=0.0654), and −0.0334 (SD=0.1145) respectively, with extinction probabilities of 0.0 for baseline and increase tourism scenarios, 1.0 for increase fishing scenario with mean estimated extinction time at 14 years, and 0.4430 for increase harbour activity scenario with mean estimated extinction time at 80.1 years. Sensitivity testing identified the percentage of adult females breeding and female mortality as the parameters most significantly impacting population trends. The simulations provided important insights into the primary factors impacting the viability of Sotalia guianensis and lay the groundwork for future population assessments and conservation plans.

Exceptionally preserved burrows of ichnogenus Asterosoma from the lower Silurian of south China: systematic ichnology, palaeoecology and implications for ecosystem recovery following the late Ordovician mass extinction

Exceptionally preserved complex burrows are described from the lower Silurian of South China, and they are identified as Asterosoma ludwigae Schlirf, 2000 , which is characterized by straight or curved bulbs that bud from an axial, vertical or horizontal, cylindrical burrow following a dichotomous or fan-like pattern. Striae and concentric lamination of burrow fills indicate that the special mining behaviour of the tracemaker reflects appendages that imprinted the burrow wall during their activities, implying that polychaetes or holothuroids could be strong candidates for the tracemaker of A . ludwigae . Abundant organic-matter-rich peloids and muddy matrix in burrow fills may consist of tracemaker's secretions or excrement. Abundant extracellular polymeric substance and clay minerals in filling sediment indicate the possible presence of microbes, implying that Asterosoma is not a simple fodinichnion, but rather created a beneficial symbiosis between tracemakers and microbes in burrows. Phanerozoic spatiotemporal distributions indicate that Asterosoma was distributed in broad habitats from deep sea to delta, but showed a strong preference for the shallow sea. Compilation of new ichnofossils and previously reported ichnotaxa from South China reveals that ichnospecies richness, burrow size and complexity all increased significantly during the late Aeronian, indicating a full recovery after the late Ordovician mass extinction.

Late Ordovician ironstone and its relation to ocean redox instability, climate and glaciation

AbstractThe 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.

Functional and phylogenetic signals in the pectoral girdle of Thalattosuchia and Dyrosauridae (Crocodylomorpha).

Crocodylomorphs have colonized various environments from fully terrestrial to fully aquatic, making it an important clade among archosaurs. A remarkable example of the rich past diversity of Crocodylomorpha Hay, 1930 is the marine colonization undergone by several crocodylomorph lineages, particularly Thalattosuchia Fraas, 1901 during the Early Jurassic-Early Cretaceous, and Dyrosauridae de Stefano, 1903 during the Late Cretaceous-Early Eocene. Thalattosuchia represents the most impressive and singular marine radiation among Crocodylomorpha, occupying various ecological niches, before enigmatically disappearing in the Cretaceous. Dyrosauridae, on the other hand, is known for surviving the end-Cretaceous mass extinction in abundance but subsequently vanished. The evolutionary path undertaken by crocodylomorphs into the aquatic environments and the reasons for their disappearance outside marine extinction events during the Mesozoic remains a mystery. Despite a well-preserved fossil record, attention has primarily centered on craniodental adaptations, overlooking the swimming-related adaptations recorded in the postcranial skeleton. This research primarily involves a comprehensive examination of the pectoral girdle of the most representative members of Thalattosuchia and Dyrosauridae, highlighting their evolutionary trajectories over time. Additionally, this work aims to test the phylogenetic signal residing in the postcranial anatomy of Crocodylomorpha. As such, the most recent and complete Crocodylomorpha phylogenetic dataset has been repurposed: 42 new postcranial characters have been added and several others have been revised to address our phylogenetic question. We stress that postcranial anatomy constitutes an important tool supply to better understand the relations of extinct crocodyliforms, but also offers insights on their development, ecology, and biomechanics.

An exceptionally preserved fossil assemblage from the early Jurassic of Chongqing (China) reveals a complex lacustrine ecosystem

One of the five greatest mass extinction events in the history of life occurred at the end of the Triassic (~ 201 million years ago), as confirmed by profound loss of life in marine realm. Terrestrial ecosystems were also suffered but the extent of life loss and timing of subsequent recovery remain equivocal, largely because of scarcity of fossil record. Here we report an exceptionally-preserved fossil assemblage, Yuzhou Biota, from the Sinemurian (~ 199–193 Ma), Early Jurassic lacustrine deposits of northern Chongqing, China. The biota documents the first known trophically complex lacustrine ecosystem after the end-Triassic extinction in China, including various representative species ranging from primary consumers (e.g., ostracods, conchostracans, gastropods and bivalves) to large predators (e.g., a variety of jawed fishes and pliosauroids). The most striking feature is its diversified aquatic vertebrates; the hybodontiforms, ceratodontiforms, ptycholepiformes, ginglymodians and pliosauroids from the biota all represent their first occurrences above the Triassic-Jurassic boundary in China. As such, the discovery enriches our understanding of the faunal turnover of aquatic vertebrates following the end-Triassic mass extinction, and provides a novel window on the Early Jurassic lacustrine ecosystems.

Obscured star clusters in the inner Milky Way. How many massive young clusters are still awaitingdetection

Milky Way star clusters provide important clues about the history of star formation in our Galaxy. However, the dust in the disk and in the innermost regions hides them from the observers. Our goal is twofold. First, to detect new clusters -- we have applied the newest methods of detecting clusters with the best available wide-field sky surveys in the mid-infrared because they are the least affected by extinction. Second, we address the question of cluster detection's completeness, for now limiting it to the most massive star clusters. This search is based on the mid-infrared Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE), to minimize the effect of dust extinction. The search Ordering Points To Identify the Clustering Structure (OPTICS) clustering algorithm was applied to identify clusters, after excluding the bluest, presumably foreground sources, to improve the cluster-to-field contrast. The success rate for cluster identification was estimated with a semi-empirical simulation that adds clusters, based on the real objects, to the point source catalog, to be recovered later with the same search algorithm that was used in the search for new cluster candidates. As a first step, this was limited to the most massive star clusters with a total mass of sim 10$^4$\,M$_ odot$. Our automated search, combined with inspection of the color-magnitude diagrams and images, yielded 659 cluster candidates; 106 of these appear to have been previously identified, suggesting that a large hidden population of star clusters still exists in the inner Milky Way. However, the search for the simulated supermassive clusters achieves a recovery rate of 70-95\,&lt;!PCT!&gt;, depending on the distance and extinction toward them. The new candidates -- if confirmed -- indicate that the Milky Way still harbors a sizeable population of unknown clusters. However, they must be objects of modest richness, because our simulation indicates that there is no substantial hidden population of supermassive clusters in the central region of our Galaxy.

Tracing the range shifts of African tree ferns: Insights from the last glacial maximum and beyond

African tropical forests are experiencing rapid decline as a result of several factors, including increasing population pressure, recurrent wildfires, selective logging practices, land use changes, intensified agricultural activities, and other social and economic issues. Using MaxEnt, paleoclimatic data, and future climate scenarios, the present study seeks to explore the presence of tree ferns in tropical and Saharan Africa during the Last Glacial Maximum, African Holocene Humid Period (AHHP; ca. 14,500–5000 years ago) and to project the effects of climate change on the distribution of tree ferns in Africa under two future climatic scenarios, Representation Concentration Pathways (RCP) 4.5 and 8.5. Our study reveals that despite a significant increase in precipitation during the AHHP, precipitation distribution was variable and insufficient to support the five tree fern species examined in this study. While some tree fern species have experienced range shifts over time, we found that most of them have maintained their presence within refuge areas that probably endured the late Pleistocene extinction event. These refugia provided a haven for some tree ferns, allowing them to persist and survive amidst challenging and varying environmental conditions. This highlights tree ferns' remarkable adaptability in changing climate as well as the critical importance of these refugial areas in safeguarding their populations during climatic upheaval. Our study further demonstrates that different species respond to climate change differently, with some experiencing minimal range contractions of 2.0 %, up to more than 57.0 % range expansion in other species. Preserving refugia not only safeguards tree fern populations but also contributes to conserving overall forest biodiversity and ecosystem functioning. This knowledge is crucial for implementing targeted conservation actions that promote sustainable forest management and can mitigate the threats posed by climate change and anthropogenic activities in African closed wet forests.

Young Children Moving through Ecological Anxiety and Grief: Dancing with Demolition

ABSTRACT As the extent of planetary unraveling becomes increasingly apparent, scholars are beginning to document responses to the loss of ecological systems, mass extinctions, and climate change. However, there are few studies documenting children’s eco-anxiety responses. In this study, children’s eco-anxiety and grief became apparent when they expressed dismay at the imminent demolition of a derelict building. Children were concerned for the fate of the building, the land on which it stood, and the myriad others it sheltered. Using participatory and creative methodologies including dance, this project worked with children to tell a more-than-human story of becoming-with children-building-weeds-graffiti-dust-researchers-unhoused-bacteria-rats-and unloved others, which culminated in a video work. In this article Butler’s concept of “grievability” is extended to include those not typically thought to be “grievable.” The article concludes with a discussion about how dance improvisation allowed children to express feelings of loss and move through their eco-anxiety and grief.

Molecular Innovations Shaping Beak Morphology in Birds.

The beak, a pivotal evolutionary trait characterized by high morphological diversity and plasticity, has enabled birds to survive mass extinction events and subsequently radiate into diverse ecological niches worldwide. This remarkable ecological adaptability underscores the importance of uncovering the molecular mechanisms shaping avian beak morphology, particularly benefiting from the rapidly advancing archives of genomics and epigenomics. We review the latest advancements in understanding how genetic and epigenetic innovations control or regulate beak development and drive beak morphological adaptation and diversification over the past two decades. We conclude with several recommendations for future endeavors, expanding to more bird lineages, with a focus on beak shape and the lower beak, and conducting functional experiments. By directing research efforts toward these aspects and integrating advanced omics techniques, the complex molecular mechanisms involved in avian beak evolution and morphogenesis will be deeply interpreted.