• Precise kinetic parameters for modeling thermal ∆ 47 resetting. • Internally consistent kinetic dataset for biogenic and abiogenic calcites. • Snapshot experiments to choose suitable kinetic parameters. • High-resolution FTIR maps on water and OM distribution in belemnite rostrum. Carbonate clumped isotope (∆ 47 ) thermometry is a powerful tool to reconstruct paleotemperatures. However, episodes of heating or cooling can alter original ∆ 47 values through diffusive C O bond reordering—i.e., isotopic exchange between neighboring carbonate groups within the mineral lattice—and/or oxygen-isotope exchange between carbonate groups and water (collectively termed “thermal resetting”). Nevertheless, if precise kinetic constraints are available, altered ∆ 47 values can be utilized to reconstruct thermal histories of sedimentary basins or to restore primary ∆ 47 values from carbonates which experienced thermal resetting in their geological history. Here, we present new high-resolution heating experiments on optical (abiogenic) and belemnite (biogenic) calcite. By capturing early signals and conducting experiments at lower temperatures than in previous studies, we derive new precise disordered kinetic parameters for both materials [optical calcite: µ E = 216.47 ± 6.95 kJ mol -1 , σ E = 14.51 ± 1.22 kJ mol -1 , and v 0 = 28.61 ± 1.12 ln(min) -1 ; belemnite calcite: µ E = 180.15 ± 7.94 kJ mol -1 , σ E = 22.24 ± 2.62 kJ mol -1 , and v 0 = 27.76 ± 1.43 ln(min) -1 ]. Additionally, we present new FTIR data on pristine and heated belemnite calcite that confirms the presence of intracrystalline water and organic matter that is suggested to facilitate its faster thermal resetting. Complementary “snapshot” experiments on a diverse suite of materials reveal a systematic difference in thermal resetting behavior between biogenic and abiogenic calcites, highlighting the importance of structural and compositional characteristics in controlling resetting kinetics. These snapshot experiments can complement petrographic and geochemical methods in assessing the pristine nature of calcite samples and provide guidance for selecting the appropriate kinetic parameters for thermal modeling of different calcites.

Genomic insights into adaptation and microevolution of two novel non-AOA Nitrososphaeria, Acidarchaeum fankouense and Thermosulfuris yongpingense, in acid mine drainage ecosystems.

The Middle Jurassic represents a critical transition from greenhouse to coolhouse conditions, with a cooling episode recorded in the Callovian Stage linked to declining atmospheric CO 2 concentrations ( p CO 2 ) and notable geological activity. However, the relationship between p CO 2 fluctuations and terrestrial evidence remains unclear. Here, we report the first in situ zircon U−Pb ages from volcanic interbeds at the coal-bearing Wanbao Formation of the Mangniuhai Coal Mine, Tuquan County, Inner Mongolia, NE China. A weighted-mean age of 163.6 ± 1.2 Ma firmly placed these deposits in the Callovian. Moreover, we present the first quantitative epidermal study of Ginkgoites longifolius in this region, focusing on its abaxial stomatal parameters. Stomatal-based paleo- p CO 2 reconstruction yielded a value of 688.5 ± 140.3 ppmv, indicating relatively low p CO 2 value and a cooler climate consistent with previously recognized Callovian cooling phases. Considering the paleogeographic distribution of its habitats, these results suggest that Ginkgoites longifolius was adapted to and confined within strongly seasonal temperate−subtropical regimes. These findings are crucial for elucidating the paleoenvironmental context underlying feathered dinosaur diversification and early mammalian evolution during the Callovian. • The first in situ zircon U–Pb geochronological data 163.6 ± 1.2 Ma was reported. • Stomatal-based palaeo- p CO 2 reconstruction yields 688.5 ± 140.3 ppmv, consistent with the Callovian cooling events. • The paleogeographic distribution of Ginkgoites longifolius suggests that it was confined within seasonal temperate−subtropical regimes.

• Dike eruptibility scales with magma intrusion volume, overpressure and volatiles. • Thick crust and steep geotherms suppress dike formation. • Thicker Southern highlands crust hindered volcanic resurfacing compared to North. • Thinner Noachian crust: high & low degree melts erupt, showing variable alkalinity. • Amazonian basalts: low alkalinity, only high degree melts can traverse thick crust. Martian volcanism exhibits two key global trends: magmas evolved from alkali- and silica-rich compositions in the Noachian epoch to alkali depleted mafic compositions in the Amazonian, while spatially, young (Amazonian) volcanic resurfacing is confined to the Northern hemisphere and the Tharsis region, with no evidence of recent volcanism in the Southern highlands. A unifying model linking these observations has been lacking. Here, we investigate the relationship between spatio-temporal variations in volcanic resurfacing and the evolution of magma chemistry throughout martian geological history. By analyzing the physical conditions required for volcanic eruptions to be sourced from magma reservoirs located within the martian crust, we model how these conditions influence mantle-derived magma compositions. Our results show that dike propagation from magma chambers is controlled by crustal rheology, with dike height depending on chamber size, magma overpressure, and volatile exsolution (both in the reservoir and within the dike). During the Noachian, the thin crust allowed eruptions of both low- and high-degree mantle melts, consistent with the diverse alkalinity of ancient surface rocks. In contrast, the thickened Amazonian crust selectively filtered low-degree melts, necessitating high recharge rates in large magma reservoirs for eruptions. This filtering effect explains the alkali – depleted compositions of Amazonian basalts, as only high-degree melts could reach the surface. Our study provides a holistic framework connecting magma reservoir dynamics, crustal evolution, and the observed geochemical and spatio-temporal trends in martian volcanism.

Abstract We present comprehensive photometric and spectroscopic observations of a transitional Type Ia supernova (SN Ia), SN 2024aedt, discovered by the 2.5 m Wide Field Survey Telescope within 1 day of the explosion. Its light curve is characterized by a peak absolute magnitude of M B = −18.49 ± 0.03 mag and a decline rate of Δ m 15 ( B ) = 1.53 ± 0.36 mag, placing the object on the Δ m 15 ( B )– M B diagram in the transition region between normal and subluminous SNe Ia. Furthermore, the early color evolution and host galaxy environment of SN 2024aedt underscore its transitional nature, sharing properties with both normal and SN 1991bg–like SNe Ia. Light-curve modeling with MOSFiT yields a synthesized 56 Ni mass of 0.414 ± 0.042 M ⊙ and a total ejecta mass of 0.548 ± 0.108 M ⊙ . A comparison with theoretical models suggests that the evolutionary trend can be broadly explained by both delayed-detonation and double-detonation (DDet) scenarios, while possible early-excess emissions predicted by DDet cannot be identified given the limited detections soon after the SN explosion. Although the overall spectral evolution of SN 2024aedt is similar to that of other transitional SNe Ia, the spectroscopic comparison reveals diversity in the early-phase blue-end features, which becomes more homogeneous at later phases. This result indicates the importance of early-time observations in understanding the origin of SN Ia diversity.

The origin of the Testudo graeca complex has been suggested to be in the Caucasus. Poor fossil records and incomplete preservation of available fossils limit deep-time reconstructions of the paleobiogeographic history of the complex. The present work describes recently discovered tortoise species found from the Early Pliocene Jradzor site, Armenia. Apart from being one of the few well-preserved and complete species of the genus in the fossil record, the Jradzor species is the only well-dated (∼4.16 and 3.98 Ma) form among fossil representatives of the genus. The tortoise material is numerous and comprises several complete and partial shells, including some rare cranial elements and numerous postcranial bones, including the presence of bony thigh spurs. The material clearly belongs to a testudinid taxon, based on the alternating neural plates, the coincidence between the costal/peripheral sutures and the pleural/marginal sulci, the presence of a well-developed epiplastral lip, and the complete fusion of the trochanters of the femur, reaching an average carapace length of 30 cm. Furthermore, the presence of a clear hypo-xiphiplastral hinge on the plastron indicates that the Jradzor tortoise is a member of the true Testudo (or sensu stricto ) lineage. Our morphological and phylogenetic analysis placed the Jradzor tortoise within the context of the Eurasian Testudinini, showing that the recovered material should be described as a new species, that is phylogenetically placed as a sister group to the extant Testudo graeca complex. The new material allows an evaluation of the validity of previously known and relevant taxa and their inclusion in a new phylogenetic analysis like Testudo eldarica and Testudo kuchurganica , excluding Testudo burtsсhaki that should be considered as a nomen dubium. The new material presented herein sheds light on the origin and early evolution of the modern Mediterranean tortoises.

The behavior of subducted slabs in the deep mantle is crucial for understanding Earth's evolution and mantle dynamics. Seismic observations reveal widespread slab stagnation at around 1000 km, yet no major phase transitions have been found at that depth, leaving the underlying mechanisms enigmatic. Here we show that sluggish kinetics of the post-garnet transformation could induce a critical density deficit within subducting slabs. This deficit sustains metastable garnet over tens of millions of years, effectively stalling slabs at the uppermost lower mantle. Our results reveal that slab stagnation at this depth is transient and inherently tied to delayed phase transformation kinetics, consistent with geophysical inferences. This offers an alternative explanation for slab stagnation in a pyrolitic mantle without requiring long-standing rheological or chemical explanations alone. These findings highlight a critical, yet underexplored, role of phase transformation kinetics in slab behavior and deep mantle dynamics.

The organic matter (OM) of the coal-bearing terrigenous strata of the Tunguska Group (C2–P) and the Khanar Formation (C2–3) as well as the Devonian carbonate rocks of the North Tunguska oil and gas region (OGR) has a complex geologic history due to strong heating by traps. This explains the reduced values of genetic biomarker parameters, such as n-C27/n-C17 (n-alkanes), C29/C27 (steranes), and hopanes/tricyclanes, in a number of terrestrial bitumens and the possible change in tricyclane index ITC as a result of the accumulation/dispersion of migrating low-molecular compounds. The sterane maturity coefficient in most samples has undergone thermal inversion and is unfit for determining the grade of catagenesis. Devonian samples probably contain marine OM (low δ13C; high HI in the insoluble residue and kerogen; in the Pr/n-C17–Ph/n-C18 diagram of kerogen, the H/Cat values lie at the boundary or in the field of type II kerogen; also, low n-C27/n-C17 and C29/C27 values are typical), although the isotope and pyrolytic characteristics of the kerogen of the Manturovka Formation (D1) are distorted, probably because of high-grade catagenesis. The coal-bearing strata contain terrestrial OM (with a low HI of kerogen; in the Khanar Formation, it is additionally characterized by high n-C27/n-C17, C29/C27 steranes, and hopanes/tricyclanes ratios). The genetic characteristics of the saturated fractions of bitumens (n-C27/n-C17, C29/C27 steranes, and hopanes/tricyclanes) in several upper Paleozoic samples are significantly distorted because of the catagenetic redistribution of compounds, with a predominance of low-molecular ones. According to the elemental composition of kerogen, a half of the samples of the Khanar Formation and the Tunguska Group can be assigned to type III kerogen, and the other half, to type IV kerogen. Because of trap intrusions, the catagenesis grade of Carboniferous–Permian OM generally increases upsection from MC2 to apocatagenesis (which is evidenced by the changes in RVto, MPI-1 of the aromatic fraction of bitumen, and H/Cat of kerogens and asphaltenes).

ABSTRACT The deep carbon cycle and carbon reservoir in the Earth’s lower mantle are of great interest in high-pressure mineral physics since they are thought to have important contributions to the dynamical and chemical evolution of the solid Earth. A high-pressure silicate-carbonate, CaSiC2O7, has recently been discovered, but its stability in reactions with surrounding mantle materials remains unclear. To investigate this, we perform ab initio density functional calculations assuming several reactions with deep mantle mineral components. The calculated results show that this new class of carbon-bearing silicate compound is stabilized by the reactions of CaCO3 and MgCO3 with SiO2, CaSiO3 perovskite, and MgSiO3 bridgmanite at different pressures and inversely inhibits the stabilization of CaCO3, MgCO3, and CaC2O5 above 60 GPa. These results suggest that CaSiC2O7 represents an important host for carbon in the Earth’s deep mantle and influences the form in which carbon is stored and transported under lower mantle conditions.

Abstract. Physics-based morphodynamic modeling is essential for advancing river management science and understanding Earth's geomorphological evolution processes. However, their computational demands and long processing times hinder long-term applications. This paper introduces and tests a robust Deep Learning (DL) framework that opens the door to overcoming these challenges through integrating convolutional neural networks (CNNs) with long short-term memory (LSTM) architectures, trained using outputs from the physics-based HEC-RAS model. This framework facilitates rapid and continuous spatiotemporal predictions of hydrodynamic parameters and morphodynamic responses of flood events. Hydrodynamic predictions showed strong performance across the testing dataset, with mean RMSEs of 0.15 m and 0.04 m s−1 for water depth and flow velocity, respectively. Bed change predictions also demonstrated promising results, with normalized RMSE of 27 % and R2 of 0.93. This novel approach generates predictions 4700 times faster than traditional physics-based computational models, representing a paradigm shift in long-term river evolution simulations and opening new opportunities for fluvial morphodynamic modeling.

The Middle-Late Jurassic Yanliao Biota and the Early Cretaceous Jehol Biota in northeastern China are renowned for their numerous exceptional fossils of feathered non-avian dinosaurs and early avialans, which are pivotal for elucidating the origins and evolutionary trajectories of birds. The Early Cretaceous witnessed a rapid diversification of terrestrial biotas, with the Jehol Biota serving as one of the most typical and famous assemblages in China from this era. In this report, we present two isolated feather specimens recovered from the oldest sedimentary strata of the Dabeigou Formation, located within the Luanping Basin in northern Hebei Province, China. Both feather specimens are preserved as carbonized residues, and morphological analyses indicate that they represent some of the earliest feathered theropods from the Jehol Group reported to date, potentially including avian taxa. This discovery not only enriches the evidence for diverse terrestrial vertebrate groups of the Jehol Biota but also signifies the establishment of a complex ecosystem during the biota's early evolutionary stages.

Abstract We report the discovery of a radio-quiet to radio-loud transition in the narrow-line Seyfert 1 galaxy J1105+1452. The source has undergone a long-term evolution from a radio-quiet state in the 1990s to a persistently radio-bright state after 2017. Post-2017 flux densities in the 0.8–7 GHz range cluster between 32 and 43 mJy, whereas the 144 MHz flux density is only 1.94 ± 0.23 mJy. This indicates strong low-frequency suppression from a compact, absorbed component. Modeling the radio spectral energy distribution with a synchrotron self-absorption model yields a turnover frequency ν p = 0.48 ± 0.03 GHz and a peak flux density S p = 38.9 ± 4.7 mJy. These parameters classify J1105+1452 as a megahertz peaked-spectrum source, consistent with the new episode of an early-stage compact jet. Under the assumption of equipartition, we derive an intrinsic physical radius R ∼ 0.68 pc and an average apparent expansion velocity β app ≈ 0.64. The observed brightness temperature T b ≈ 6.0 × 10 11 K necessitates a Doppler factor δ ≈ 12, implying a relativistic jet viewed at θ ≲ 5°. Despite the dramatic radio evolution, the X-ray spectrum remains stable and steep (Γ ≃ 3.0), suggesting that the X-ray emission remains dominated by the disk/corona, while the radio band has become jet dominated. Our results identify J1105+1452 as a rare radio changing-state NLSy1, providing a unique laboratory for studying the birth and early evolution of relativistic jets at high Eddington ratios.

The flexible job shop scheduling problem (FJSP) has been extensively researched over the past decade. However, the integration of preventive maintenance (PM), transportation times, and energy efficiency remains under-explored. This paper addresses the energy-efficient flexible job shop scheduling problem with preventive maintenance and transportation times (EFJSP-PMT). To minimize both makespan and total energy consumption, a multi-population optimization algorithm with adaptive strategy and competition (MPOA-ASC) is proposed, featuring distinct early and later evolution phases. In the early evolution phase, we develop a hybrid heuristic initialization method, a new population division strategy, an adaptive mechanism for crossover and mutation probabilities, and three specialized local search operators. In the later phase, a novel inter-population competition mechanism is introduced to optimize the allocation of computational resources and enhance convergence performance. Extensive experimental results demonstrate that the proposed MPOA-ASC significantly outperforms state-of-the-art algorithms in solving the EFJSP-PMT.

Abstract Determining the sequence of the transmitted founder virus, the virus that establishes infection in a new host, is critical for understanding early viral dynamics and evolution. Methods to estimate transmitted founder virus sequences using ancestral sequence reconstruction (ASR) require either sequences collected early in infection or longitudinal samples that can capture the evolutionary history of the viral sequences, which can be challenging to collect. In human immunodeficiency virus (HIV) infection, viral genomes are integrated into host cells which can persist, creating a proviral archive of the evolutionary history of the virus. We can potentially utilize these proviral sequences, which can be collected later during infection and while the individual is on therapy, to perform ASR to estimate founder virus sequences. We analyzed a previously described data set of twelve participants from Zambia who had HIV sequences collected within months of infection and proviral sequences collected before and after suppressive therapy initiation. We investigated the accuracy of root placement and founder virus sequence reconstruction in these individuals from their proviral sequences using a variety of phylogenetic methods. We had limited success in reconstructing founder virus sequences across all ancestral sequence reconstruction and rooting methods. However, we observed lower error in founder virus sequence reconstruction with participants that had proviral sequences similar to their founder sequence. Our results highlight a need for new methods to be developed in order to effectively reconstruct founder virus sequences from proviral sequences.

Detecting chromosomal copy-number alterations together with protein-defined cell states in intact tissue is critical for understanding early clonal evolution and microenvironmental interactions in cancer. We developed ORION-FISH, which integrates high-plex tissue imaging with a morphology-preserving DNA-FISH workflow and single-cell registration, yielding measurements concordant with clinical FISH. In High Grade Serous Ovarian Carcinoma (HGSOC), ORION-FISH recapitulated known chromosomal changes while revealing subclonal heterogeneity missed by targeted sequencing. Applied to serous tubal intraepithelial carcinomas (STICs), precursors of HGSOC, ORION-FISH identified intermixed epithelial cells with MYC or CCNE1 copy-number gains, as well as concurrent alterations associated with distinct immune microenvironments. In addition, epithelial cells with MYC and CCNE1 copy-number gains were detected in morphologically normal fallopian tube epithelium, along with rare MDM4 increases across epithelial lineages. Together, ORION-FISH provides a framework linking chromosomal copy number states to protein-defined phenotypes within preserved tissue architecture, enabling context-aware interrogation of early copy-number diversification at single-cell resolution.

ABSTRACT Numerous Palaeozoic ophiolites occur in the Changning – Menglian suture zone in southwestern Yunnan Province, China, which are important for reconstructing the evolution of the Proto- and Paleo-Tethys oceans. In this study, zircon U-Pb age and whole-rock geochemical data were acquired for amphibolites in the Nantinghe ophiolites within this suture zone, to constrain the timing of closure of the Proto-Tethys Ocean. The amphibolites can be classified into epidote amphibolites and migmatitic garnet-bearing amphibolites, with the latter containing leucocratic and melanocratic domains. Zircon U-Pb dating yielded 206Pb/238U ages for zircon cores of 466–456 and 480.8 ± 5.1 Ma (weighted-mean), which represent the protolith age. Zircon rims have ages of 445–436 Ma, which date metamorphism or anatexis. The epidote amphibolites have relatively low SiO2 and high Al2O3, MgO, and TFe2O3 contents, are light rare earth element (REE) enriched and heavy REE depleted, and have negative Rb, Th, Nb, Ta, Zr, and Hf anomalies in trace element diagrams. These geochemical affinities suggest a protolith origin from arc-related magmatism. Synthesizing documented records of Early Palaeozoic calc‑alkaline igneous rocks, these rock suites demonstrate that subduction of the Paleo‑Tethys Oceanic lithosphere had initiated in the Early Ordovician with its peak activity occurring in the Middle Ordovician (466–456 Ma).The metamorphic ages (445–436 Ma) of the garnet-bearing amphibolites are comparable to those of garnet amphibolites in Taoxinghu and high-pressure mafic granulites in Xiangtaohu in the Longmucuo – Shuanghu area. They record the timing of continental collision accompanying closure of the Proto-Tethys Ocean. The Longmucuo – Shuanghu – Changning – Menglian suture zone had a similar Early Palaeozoic tectonic evolution to that of the Proto-Tethys Ocean in areas such as North Qilian, East Kunlun, and northern Qaidam.

Abstract In this paper we present 16 early-phase type Ia supernovae (SNe Ia) discovered during the pilot survey of the 2.5-meter Wide Field Survey Telescope ("WFST-PS") from March 4 to July 10, 2024, including three SNe Ia with early-excess emission features (EExSNe Ia). The discovery magnitude of the 16 WFST-PS early-phase SNe is at least 3 mag fainter than their peak brightness. A large scatter of color indices is found in approximately the first 10 days of supernova explosions, indicating diverse photometric behaviors in the early phase. Three EExSNe Ia show relatively brighter peak luminosities and longer rise time compared to those of non-EExSNe Ia. The results indicate that current theoretical models require further refinement to fully capture the early photometric evolution of SNe Ia. Based on the initial high-cadence ugr-band data from the WFST-PS survey, we emphasize that early near-ultraviolet (NUV) observations are indispensable for placing tight constraints on the explosion mechanisms and progenitor systems of SNe Ia.

The analysis has been made on the modern data about the Neoproterozoic – Early Paleozoic geodynamic evolution of the southern flank of the Siberian Platform in order to identify the probable time and place of formation of hydrocarbons in sedimentary basins and their further migration from the foci of oil and gas formation to the zones of their accumulation, namely to the sedimentary deposits of the Chora formation of the Vendian Moty group (productive Parfenovo horizon). The conditions for the accumulation of hydrocarbons could arise in sedimentary basins of the passive margin of the Siberian craton, formed in the Neoproterozoic (710–650 Ma) after the breakup of the supercontinent Rodinia, separation of the Siberian craton therefrom and opening of the Paleoasian Ocean, as well as in the peripheral foreland basin, formed after the transformation of this passive margin at about 610 Ma ago. In the Baikal part of the Siberian Platform, the accumulation of hydrocarbon-containing sediments could occur in the rocks of the Uluntuy and Kachergat formations of the Baikal group, formed in the basin of the passive continental margin and the foreland basin, respectively. As a result of the large-scale Late Cambrian-Ordovician accretion-collision events that mark the formation of the Central Asian Orogenic Belt, hydrocarbons migrated westward from the Vendian deposits of the Uluntuy and Kachergat formations to the sedimentary sequences of the Chora formation of the Moty group, having formed the deposits of the Angara-Kovykta oil and gas accumulation zone (Angara-Lena oil and gas bearing region). Since over 90 % of the world hydrocarbon reserves are confined to sedimentary sequences of passive margins and foreland basins, it can be assumed that the proposed hypothesis may explain the nature of the origin of hydrocarbons, their migration, and accumulation in the deposits of the Angara-Lena oil and gas region. Subsequent processes, which significantly affected the redistribution of hydrocarbons specifically within this oil and gas region, were caused by neotectonic activation, which contributed to the formation of deposits in the Angara-Kovykta oil and gas accumulation zone.

Cnidarians are classically defined by a single oral opening, a hallmark of the "blind gut" model in early animal evolution. Here, we identify a pressure-sensitive aboral valve in Nematostella vectensis that operates independently of egestion. This valve dissipates elevated hydraulic pressure during morphogenesis, expelling fluid through transient epidermal ruptures triggered by muscular ring opening. This unexpected function was revealed by a comprehensive analysis of mesogleal basement membrane biogenesis. We show that the global dynamics of this extracellular matrix transduce muscular hydraulics to drive tissue rearrangement and stabilize shape, while localized FGFRb-dependent matrix remodeling establishes the aboral valve. By positioning the mesoglea as an integrator of biomechanics, tissue remodeling, and aboral valve function, these findings expand nonbilaterian openings beyond the digestive paradigm as a hydraulic regulator.

Cooperation in social insect colonies depends on complex chemical communication, requiring a large array of chemosensory receptors. Ant odorant receptors (ORs) were dramatically expanded compared to other insects, most notably in the "9-exon" subfamily, which was implicated in responding to cuticular hydrocarbons, a major class of signalling compounds. These observations indicate adaptive evolution of olfactory functions, but this process was never studied in the context of the evolution of specific sociobiological traits. The Global Ant Genomics Alliance has compiled 163 high-quality ant genomes, enabling detailed study of OR evolution in unprecedented detail. Analysing 55,068 ORs across the phylogeny, we tested for association between sociobiological traits and adaptive evolution of ORs, including gene duplication and adaptive sequence evolution. We identified strong enrichment of positive selection on 9-exon ORs in the ancestor of the formicoid clade, which evolved larger colonies and greater reproductive division of labour. This result indicates a key role of chemical communication in the early evolution of complex social organization. We also observed enrichment of positive selection on 9-exon ORs associated with the recent evolution of continuous worker polymorphism in multiple lineages. Surprisingly, the evolution of other sociobiological traits was associated with reduced positive selection on ORs. These results suggest that worker polymorphism involves more extensive adaptation of chemical communication compared to other aspects of ant sociobiology. By analysing the most comprehensive OR dataset to date, we provide new insights into the specific context in which ORs played a major role in the elaboration of social traits in ants.