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We investigate the influence of earthquake source characteristics and geological site parameters on fault scarp morphologies for thrust and reverse fault earthquakes using geomechanical models. A total of 3434 distinct element method (DEM) model experiments were performed to evaluate the impact of the sediment depth, density, homogeneous and heterogeneous sediment strengths, fault dip, and the thickness of unruptured sediment above the fault tip on the resultant coseismic ground surface deformation for a thrust or reverse fault earthquake. A machine learning model based on computer vision (CV) was applied to obtain measurements of ground surface deformation characteristics (scarp height, uplift, deformation zone width, and scarp dip) from a total of 346,834 DEM model stages taken every 0.05 m of slip. The DEM dataset exhibits a broad range of scarp behaviors, generating monoclinal, pressure ridge, and simple scarps—each of which can be modified by hanging wall collapse. The parameters that had the most influence on surface rupture patterns are fault displacement, fault dip, sediment depth, and sediment strength. The DEM results comprehensively describe the range of historic surface rupture observations in the Fault Displacement Hazards Initiative (FDHI) dataset with improved relationships obtained by incorporating additional information about the earthquake size, fault geometry, and surface deformation style. We suggest that this DEM dataset can be used to supplement field data and help forecast patterns of ground surface deformation in future earthquakes given specific anticipated source and site characteristics. 

Abstract Locomotor evolution in synapsids involved numerous functional shifts associated with the transition from sprawled to erect limb postures on the line to therian mammals. Given that bone structure frequently reflects functional requirements, this study investigated evolutionary changes in synapsid humerus and femur proportions as a lens to evaluate functional shifts through time. A total of 936 bones were measured, representing 330 species across the full 320+ million years of synapsid history. This dataset was used to test whether transformations in stylopod proportions are consistent with inferred changes in bone loading mechanics, alignment of joint and muscle forces, muscular control of the shoulder and hip, and differential support of body weight by the fore‐ and hindlimbs. As variation in bone dimensions may also correlate with bone or body size, this study first developed a novel approach for calculating species‐specific, size‐corrected measures of bone proportions. By disentangling the effect of body size from functional signals recorded in bone geometry, this then enabled a node‐to‐node appraisal of how bone allometry itself evolved through time. Ancestral state reconstruction of size‐corrected stylopod proportions reveals trends that broadly support many hypothesized shifts in locomotor biomechanics along the therian stem lineage. However, patterns of transformation are frequently complex, suggesting functional mosaicism, and stylopod proportions that typify therians as a whole are often not achieved until crown Theria itself. Several instances of temporary trend reversal are also inferred, particularly within non‐mammalian cynodonts, indicating greater functional or ecological diversification in this group. 

ABSTRACT Contractualist moral theories view morality as a matter of mutually beneficial agreements among rational agents. Compared to its rivals in moral philosophy–consequentialism, deontology, and virtue ethics–contractualism has only recently started to attract attention in empirical work on the cognitive science of morality. Is it fruitful to adopt a contractualist lens to better understand how moral cognition works? After introducing the main contractualist theories in contemporary moral philosophy, I present five reasons to take inspiration from this family of normative theories to develop descriptive accounts of morality. Then, I review how the contractualist framework has been used to contribute to our understanding of moral cognition at three interrelated levels of analysis: Morality's evolutionary logic, its cognitive organization, and the specific cognitive processes and forms of reasoning involved in moral judgment and decision making. First, several evolutionary accounts of morality argue that its evolutionary logic must be understood in contractualist terms. Second, resource‐rational contractualism proposes that the subcomponents of moral cognition–including well‐studied rule‐ and outcome‐based mechanisms, and much less studied agreement‐based processes–are organized to efficiently approximate the outcome of explicit negotiation under resource constraints. Third, recent empirical developments suggest that three characteristically contractualist forms of reasoning–virtual bargaining, we‐reasoning, and universalization–can be involved in producing moral judgments and decisions in a variety of contexts. Beyond the traditional distinction between rules and consequences, these various research programs open a third way for the cognitive science of morality, one based on agreement. This article is categorized under:Psychology > Reasoning and Decision MakingEconomics > Interactive Decision‐MakingPhilosophy > Value 

Abstract Following large earthquakes, viscoelastic stress relaxation may contribute to postseismic deformation observed at Earth's surface. Mechanical representations of viscoelastic deformation require a constitutive relationship for the lower crust/upper mantle material where stresses are diffused and, for non‐linear rheologies, knowledge of absolute stress level. Here, we describe a kinematic approach to representing geodetically observed postseismic motions that does not require an assumed viscoelastic rheology. The core idea is to use observed surface motions to constrain time‐dependent displacement boundary conditions applied at the base of the elastic upper crust by viscoelastic motions in the lower crust/upper mantle, approximating these displacements as slip on a set of dislocation elements. Using three‐dimensional forward models of viscoelastically modulated postseismic deformation in a thrust fault setting, we show how this approach can accurately represent surface motions and recover predicted displacements at the base of the elastic layer. Applied to the 1999 Chi‐Chi (Taiwan) earthquake, this kinematic approach can reproduce geodetically observed displacements and estimates of the partitioning between correlated postseismic deformation mechanisms. Specifically, we simultaneously estimate afterslip on the earthquake source fault that is similar to previous estimates, along with slip on dislocations at the base of the elastic layer that mimic predictions from viscous stress dissipation models in which viscosity is inferred to vary three‐dimensionally. A use case for the dislocation approach to modeling viscoelastic deformation is the estimation of spatiotemporally variable fault slip processes, including across sequential interseismic phases of the earthquake cycle, without assuming a lower crust/upper mantle rheology. 

Abstract This essay examines how the now-adult children of the disappeared in The Gambia express their grief through various art forms, focusing on the elegy. Peter Sacks, defines the elegy as “a poem of mortal loss and consolation” (Sacks 3). The traditional functions of the elegy—lament, praise, and consolation—respond to loss by expressing grief and honoring the deceased. The essay explores the mourning process of three young adults through songwriting, letter writing, and memorial tattoos dedicated to their fathers who disappeared during Yahya Jammeh’s dictatorship. In an Islamic context, where retaining objects of the deceased is discouraged, these children find ways to remember their lost parents without material objects. Cathy Caruth argues that “to be traumatized is precisely to be possessed by an image or event” (Caruth 4–5). Here, it is the absence of a clear image and event that haunts these children, leading to artistic creation through elegiac writing and embodied meaning-making. 

Abstract Geologic and geodetic observations provide constraints on tectonic and earthquake cycle kinematics. Block models offer one approach to integrating the effects of plate rotations, elastic strain accumulation, applied basal displacements, internal block strain, and idealized pressure sources. Here, we describe the construction of block models where spatially variable slip rates are parameterized by distance‐weighted eigenmodes operating over meshes of triangular dislocation elements. This dimensionally reduced model is recast as a quadratic programming problem with upper and lower bounds on both geologic fault slip rates and spatially variable slip deficit rates. We propose iterating over successive quadratic programming estimates with evolving slip rate bounds to find a solution consistent with specified coupling at all points on geometrically complex fault surfaces. 

This Editorial introduces the Virtual Issue ‘Nectar and nectaries’ that includes the following papers: Ballarinet al.(2024), Griersonet al.(2024), Grof‐Tiszaet al.(2025), Landucci & Vannette (2025), Liaoet al.(2025), MacNeillet al.(2025), Magneret al.(2023, 2024, 2025), Minet al.(2019), Mouet al.(2025), Parkinsonet al.(2025), Quevedo‐Caraballoet al.(2025), Ramoset al.(2025), Romero‐Bravo & Castellanos (2024), Soareset al.(2025), Turneret al.(2025), Zhaiet al.(2025), Zhanget al.(2020). Access the Virtual Issue atwww.newphytologist.com/virtualissues. 

Summary Nectar is a central bridge between angiosperms and animal mutualists. It is produced by specialized structures termed nectaries, which can be found on different plant organs. Consumption of floral nectar by pollinators and the subsequent transfer of pollen contribute to the reproductive success of both angiosperms and their pollinators. Floral nectaries have evolved many times independently, feature diverse structural organizations, and produce nectars with various compositions, which cater to a wide range of pollinators. While the nectary and its nectar have been documented for two millennia, many aspects of nectary biology are still unknown. Recent advances in genetics, genomics, and comparative analyses across diverse species have accelerated our understanding of floral nectary structures and the genetic circuits behind their formation and evolution. In this review, we summarize the recent breakthroughs in nectary research and provide a macroevolutionary framework of floral nectary evolution, focusing on the genetic mechanisms that drive nectary development and shape nectary diversity.