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Abstract Spatial patterns of stellar elemental abundances encode rich information about a galaxy’s formation history. We analyze the radial, vertical, and azimuthal variations of metals in stars, both today and at formation, in the FIRE-2 cosmological simulations of Milky Way (MW)-mass galaxies, and we compare them with the MW. The radial gradient today is steeper (more negative) for younger stars, which agrees with the MW, although radial gradients are shallower in FIRE-2. Importantly, this age dependence was present already at birth: radial gradients today are only modestly (≲0.01 dex kpc⁻¹) shallower than at birth. Disk vertical settling gives rise to negative vertical gradients across all stars, but vertical gradients of mono-age stellar populations are weak. Similar to the MW, vertical gradients in FIRE-2 are shallower at larger radii, but they are overall shallower in FIRE-2. This vertical dependence was present already at birth: vertical gradients today are only modestly (≲0.1 dex kpc⁻¹) shallower than at birth. Azimuthal scatter is nearly constant with radius, and it is nearly constant with age ≲8 Gyr ago but increases for older stars. Azimuthal scatter is slightly larger (≲0.04 dex) today than at formation. Galaxies with larger azimuthal scatter have a stronger radial gradient, implying that azimuthal scatter today arises primarily from the radial redistribution of gas and stars. Overall, spatial variations of stellar metallicities show only modest differences between formation and today; spatial variations today primarily reflect the conditions of stars at birth, with spatial redistribution of stars after birth contributing secondarily. 

Abstract Using the FIRE-2 cosmological zoom-in simulations, we investigate the temporal evolution of gas-phase metallicity radial gradients of Milky Way–mass progenitors in the redshift range of 0.4 <z< 3. We pay special attention to the occurrence of positive (i.e., inverted) metallicity gradients—where metallicity increases with galactocentric radius. This trend, contrary to the more commonly observed negative radial gradients, has been frequently seen in recent spatially resolved grism observations. The rate of occurrence of positive gradients in FIRE-2 is about ∼7% for 0.4 <z< 3 and ∼13% at higher redshifts (1.5 <z< 3), broadly consistent with observations. Moreover, we investigate the correlations among galaxy metallicity gradient, stellar mass, star formation rate (SFR), and degree of rotational support. Metallicity gradients show a strong correlation with both sSFR and the rotational-to-dispersion velocity ratio (v_c/σ), implying that starbursts and kinematic morphology of galaxies play significant roles in shaping these gradients. The FIRE-2 simulations indicate that galaxies with high sSFR ( $\log \left(\mathrm{sSFR}\right[{\mathrm{yr}}^{-1}\left]\right)\gtrsim -9.2$) and weak rotational support (v_c/σ≲ 1) are more likely—by ∼15%—to develop positive metallicity gradients. This trend is attributed to galaxy-scale gas flows driven by stellar feedback, which effectively redistribute metals within the interstellar medium. Our results support the important role of stellar feedback in governing the chemo-structural evolution and disk formation of Milky Way–mass galaxies at the cosmic noon epoch. 

Abstract Management of the Colorado potato beetle (Leptinotarsa decemlineata) is reliant on conventional insecticides that can negatively affect non-target arthropods. Calantha™ (active ingredient: ledprona) is a sprayable double-stranded RNA biopesticide specific forL decemlineataproteasome subunit beta 5 gene that triggers the RNA-interference pathway and is designed to have limited non-target effects. To test this hypothesis, we conducted two years of field trials in Idaho, Wisconsin, and Maine comparing arthropod responses to different insecticide regimes, with and without Calantha, targeting the Colorado potato beetle. Comparisons of arthropod abundance among treatments showed no evidence of effects of Calantha on non-target arthropods, including beneficials (predators, parasitoids), “neutrals” (i.e., non-pests), and other beetle species. Conventional insecticides generally showed more non-target effects, and responses were always stronger for arthropods from vacuum samples than pitfall samples. Insecticide programs featuring Calantha, especially in rotation with other biorational products, may reduce pests while preserving beneficial arthropods and contribute to biological control of arthropod pests in potato fields. 

Abstract Marine sedimentary rocks of the late Eocene Pagat Member of the Tanjung Formation in the Asem Asem Basin near Satui, Kalimantan, provide an important geological archive for understanding the paleontological evolution of southern Kalimantan (Indonesian Borneo) in the interval leading up the development of the Central Indo-Pacific marine biodiversity hotspot. In this paper, we describe a moderately diverse assemblage of marine invertebrates within a sedimentological and stratigraphical context. In the studied section, the Pagat Member of the Tanjung Formation records an interval of overall marine transgression and chronicles a transition from the marginal marine and continental siliciclastic succession in the underlying Tambak Member to the carbonate platform succession in the overlying Berai Formation. The lower part of the Pagat Member contains heterolithic interbedded siliciclastic sandstone and glauconitic shale, with thin bioclastic floatstone and bioclastic rudstone beds. This segues into a calcareous shale succession with common foraminiferal packstone/rudstone lenses interpreted as low-relief biostromes. A diverse trace fossil assemblage occurs primarily in a muddy/glauconitic sandstone, sandy mudstone, and bioclastic packstone/rudstone succession, constraining the depositional setting to a mid-ramp/mid to distal continental shelf setting below fair-weather wave base but above storm wave base. Each biostrome rests upon a storm-generated ravinement surface characterized by a low-diversityGlossifungitesorTrypanitestrace fossil assemblage. The erosional surfaces were colonized by organisms that preferred stable substrates, including larger benthic foraminifera, solitary corals, oysters, and serpulid annelid worms. The biostromes comprised islands of high marine biodiversity on the mud-dominated Pagat coastline. Together, the biostromes analyzed in this study contained 13 genera of symbiont-bearing larger benthic foraminifera, ~40 mollusk taxa, at least 5 brachyuran decapod genera, and 6 coral genera (Anthemiphyllia,Balanophyllia,Caryophyllia,Cycloseris,Trachyphyllia, andTrochocyathus), as well as a variety of bryozoans, serpulids, echinoids, and asterozoans. High foraminiferal and molluscan diversity, coupled with modest coral diversity, supports the hypothesis that the origin of the diverse tropical invertebrate faunas that characterize the modern Indo-Australian region may have occurred in the latest Eocene/earliest Oligocene. 

Premise of research. The Neogene collision of the Australian tectonic plate (Sahul) with Southeast Asia (Sunda) restructured the vegetation of both regions. The rarity of plant macrofossils from Sunda has limited the understanding of precollision vegetation and plants that migrated from Sunda to Sahul. Despite the importance of legumes in the living flora, no Malesian reproductive or pre-Neogene fossils of the Fabaceae are known.Methodology. We collected 47 plant macrofossils from the Tambak Member of the Tanjung Formation (middle-late Eocene) while surveying the Wahana Baratama coal mine near Satui, South Kalimantan, Indonesian Borneo. These fossils represent Southeast Asian forests before the Sahul-Sunda collision. We studied three isolated large (up to 72 mm in length) seeds from the upper Tambak Member, along with 43 fossil leaves and two palynological samples from the lower Tambak Member.Pivotal results. We describe the extinct legume Jantungspermum gunnellii gen. et sp. nov. The J. gunnellii seeds are flattened on one side, bilobed, and heart shaped with a long hilum (~60 mm) overlain on the suture, closely resembling Castanospermum, the Australian black bean tree. The leaves represent seven morphotypes, which include Fabaceae but are otherwise unidentifiable. One specimen preserves in situ cuticle. The palynoflora includes diverse ferns and palms, Typhaceae, Onagraceae, and forest taxa, including Podocarpaceae, Sapindaceae, and Fabaceae, indicating a largely freshwater coastal swamp environment in the lower Tambak Member.Conclusions. The Jantungspermum seeds are double the length of Castanospermum seeds, representing a closely related but extinct papilionoid taxon. The discovery suggests a Sundan precollision history, a much later Sunda-Sahul migration, and an eventual Asian extinction for the Castanospermum lineage, which today inhabits coastal rainforests of northern Australasia. The seeds represent the only known fossil relative of Castanospermum, the oldest legume fossils from Malesia, and one of the largest fossil angiosperm seeds. The new seeds, leaves, and palynomorphs provide a window into Eocene Malesian vegetation and rare macrofossil evidence of Sundan history for a living Australasian lineage. 

Abstract—The diverse and spectacular Hibisceae tribe comprises over 750 species. No studies, however, have broadly sampled across the dozens of genera in the tribe, leading to uncertainty in the relationships among genera. The non-monophyly of the genusHibiscusis infamous and challenging, whereas the monophyly of most other genera in the tribe has yet to be assessed, including the large genusPavonia.Here we significantly increase taxon sampling in the most complete phylogenetic study of the tribe to date. We assess monophyly of most currently recognized genera in the tribe and include three and thirteen newly sampled sections ofHibiscusandPavonia,respectively. We also include five rarely sampled genera and 137 species previously unsampled. Our phylogenetic trees demonstrate thatHibiscus, as traditionally defined, encompasses at least 20 additional genera. The status ofPavoniaemerges as comparable in complexity toHibiscus. We offer clarity in the phylogenetic placement of several taxa of uncertain affinity (e.g.Helicteropsis,Hibiscadelphus, Jumelleanthus,andWercklea). We also identify two new clades and elevate them to the generic rank with the recognition of two new monospecific genera: 1)BlanchardiaM.M.Hanes & R.L.Barrett is a surprising Caribbean lineage that is sister to the entire tribe, and 2)AstrohibiscusMcLay & R.L.Barrett represents former members ofHibiscus caesiuss.l.CraveniaMcLay & R.L.Barrett is also described as a new genus for theHibiscus panduriformisclade, which is allied toAbelmoschus. Finally, we introduce a new classification for the tribe and clarify the boundaries ofHibiscusandPavonia. 

Abstract Dryland ecosystems cover 40% of our planet's land surface, support billions of people, and are responding rapidly to climate and land use change. These expansive systems also dominate core aspects of Earth's climate, storing and exchanging vast amounts of water, carbon, and energy with the atmosphere. Despite their indispensable ecosystem services and high vulnerability to change, drylands are one of the least understood ecosystem types, partly due to challenges studying their heterogeneous landscapes and misconceptions that drylands are unproductive “wastelands.” Consequently, inadequate understanding of dryland processes has resulted in poor model representation and forecasting capacity, hindering decision making for these at‐risk ecosystems. NASA satellite resources are increasingly available at the higher resolutions needed to enhance understanding of drylands' heterogeneous spatiotemporal dynamics. NASA's Terrestrial Ecology Program solicited proposals for scoping a multi‐year field campaign, of which Adaptation and Response in Drylands (ARID) was one of two scoping studies selected. A primary goal of the scoping study is to gather input from the scientific and data end‐user communities on dryland research gaps and data user needs. Here, we provide an overview of the ARID team's community engagement and how it has guided development of our framework. This includes an ARID kickoff meeting with over 300 participants held in October 2023 at the University of Arizona to gather input from data end‐users and scientists. We also summarize insights gained from hundreds of follow‐up activities, including from a tribal‐engagement focused workshop in New Mexico, conference town halls, intensive roundtables, and international engagements. 

Abstract Extreme heat events are a threat to human health, productivity, and food supply, so understanding their drivers is critical to adaptation and resilience. Anticyclonic circulation and certain quasi-stationary Rossby wave patterns are well known to coincide with heatwaves, and soil moisture deficits amplify extreme heat in some regions. However, the relative roles of these two factors in causing heatwaves is still unclear. Here we use constructed circulation analogs to estimate the contribution of atmospheric circulation to heatwaves in the United States in the Community Earth System Model version 1 (CESM1) preindustrial control simulations. After accounting for the component of the heatwaves explained by circulation, we explore the relationship between the residual temperature anomalies and soil moisture. We find that circulation explains over 85% of heatwave temperature anomalies in the eastern and western United States but only 75%–85% in the central United States. In this region, there is a significant negative correlation between soil moisture the week before the heatwave and the strength of the heatwave that explains additional variance. Further, for the hottest central U.S. heatwaves, positive temperature anomalies and negative soil moisture anomalies are evident over a month before heatwave onset. These results provide evidence that positive land–atmosphere feedbacks may be amplifying heatwaves in the central United States and demonstrate the geographic heterogeneity in the relative importance of the land and atmosphere for heatwave development. Analysis of future circulation and soil moisture in the CESM1 Large Ensemble indicates that, over parts of the United States, both may be trending toward greater heatwave likelihood. 

Hybrid yeast strain co-produces isobutanol and ethanol at high yields. Reducing hydrolysis enzyme loading and enhancing xylose conversion greatly impact the economic potential of the biorefinery.