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Synopsis Over the course of development, sensory systems must integrate specialized cells and tissues to generate a functional unit. A robust example of this type of integration is the lateral line, a mechanosensory system in fishes and amphibians that senses changes in water movement. Over the past century, numerous reports noted that the principal organs of the lateral line—neuromasts—co-localize to the position of ossification centers for bones of the facial skeleton. More recent work in the freshwater model system, Astyanax mexicanus, revealed facial bones of the suborbital complex frequently fuse in a manner consistent with approximated neuromasts. In cave dwelling morphs, which lack a structural eye, positioning of the neuromasts encircling the orbit differ from closely related, eyed surface-dwelling morphs. This suggests facial bone fusion patterns are a function of eye regression, which interferes with neuromast positioning early in development. Here, we compared adult bone fusion patterns from individuals derived from three cavefish populations derived from at least two independent cave colonizations—the Pachón, Tinaja, and Molino caves. Interestingly, despite established asymmetries impacting the cavefish craniofacial complex, no asymmetric bias was observed in facial bone fusion. Surface fish showed minimal fusion, however cave morphs showed substantial facial bone fusion, which varied in severity by cave population. Facial bone fusion is therefore not a simple function of eye regression, since each eyeless cavefish population harbored different patterns of fusion severity. We propose intra-population variation in bone fusion is a function of the timing of eye degeneration. Early and rapid eye degeneration (as in Pachón cavefish) likely has a more profound effect on neuromast positioning, and consequential bone fusion patterns. Tinaja and Molino cavefish have slower and more gradual eye regression, likely interfering less with neuromast positioning. This results in fewer approximated neuromasts, and fusions between neighboring facial bones. This study showcases the integrated nature of sensory-skeletal development, a poorly understood phenomenon. Moreover, aberrations impacting this integration—such as eye loss in cave dwelling fish—can lead to remarkable intraspecific (and intra-population) variation. 

Can AI systems trained on the scientific record up to a fixed point in time forecast the scientific advances that follow? Such a capability could help researchers identify collaborators and impactful research directions, and anticipate which problems and methods will become central next. Weintroduce PreScience—a scientific forecasting benchmark that decomposes the research process into four interdependent generative tasks: collaborator prediction, prior work selection, contribution generation, and impact prediction. PreScience is a carefully curated dataset of 98K recent AIrelated research papers, featuring disambiguated author identities, temporally aligned scholarly metadata, and a structured graph of companion author publication histories and citations spanning 502K total papers. We develop baselines and evaluations for each task, including LACERScore, a novel LLM-based measure of contribution similarity that outperforms previous metrics and approximates inter-annotator agreement. We find substantial headroom remains in each task—e.g. in contribution generation, frontier LLMs achieve only moderate similarity to the ground-truth (GPT5, averages 5.6 on a 1-10 scale). When composed into a 12-month end-to-end simulation of scientific production, the resulting synthetic corpus is systematically less diverse and less novel than human-authored research from the same period. 

Adhesives that excel in wet or underwater environments are critical for applications ranging from healthcare and underwater robotics to infrastructure repair. However, achieving strong attachment and controlled release on difficult substrates, such as those that are curved, rough, or located in diverse fluid environments, remains a major challenge. Here, an octopus‐inspired adhesive with strong attachment and rapid release in challenging underwater environments is presented. Inspired by the octopus's infundibulum structure, a compliant, curved stalk, and an active deformable membrane for multi‐surface adhesion are utilized. The stalk's curved shape enhances conformal contact on large‐scale curvatures and increases contact stress for adaptability to small‐scale roughness. These synergistic mechanisms improve contact across multiple length scales, resulting in switching ratios of over 1000 within ≈30 ms with consistent attachment strength of over 60 kPa on diverse surfaces and conditions. These adhesives are demonstrated through the robust attachment and precise manipulation of rough underwater objects. 

As DNA sequencing technology continues to rapidly improve, studies investigating the microbial communities of host organisms (i.e., microbiota) are becoming not only more popular but also more financially accessible. Across many taxa, microbiomes can have important impacts on organismal health and fitness. To evaluate the microbial community composition of a particular microbiome, microbial DNA must be successfully extracted. Fecal samples are often easy to collect and are a good source of gut microbial DNA. Additionally, interest in the avian preen gland microbiome is rapidly growing, due to the importance of preen oil for many aspects of avian life. Microbial DNA extractions from avian fecal and preen oil samples present multiple challenges, however. Here, we describe a modified PrepMan Ultra Sample Preparation Reagent microbial DNA extraction method that is less expensive than other commonly used methodologies and is highly effective for both fecal and preen oil samples collected from a broad range of avian species. We expect our method will facilitate microbial DNA extractions from multiple avian microbiome reservoirs, which have previously proved difficult and expensive. Our method therefore increases the feasibility of future studies of avian host microbiomes. 

Abstract Among closely related species, host phylogenetic relationships are typically a stronger predictor of gut microbiome composition than environmental variation. However, the relative impact of genetic admixture caused by hybridization versus environmental variation on gut microbiome communities is poorly understood. To explore this knowledge gap, we used fecal metabarcoding to characterize chickadee gut microbiomes along a hybrid zone transect in natural environments and after transfer to a common, controlled environment. We collected fecal samples from nestling black‐capped (Poecile atricapillus), Carolina (Poecile carolinensis), and hybrid chickadees immediately after removal from their nests and twice after entering captivity and experiencing common diet and environmental conditions. To characterize gut microbiome communities, we extracted fecal DNA and sequenced the V3–V4 region of the 16S rRNA gene using Illumina MiSeq. Overall,FirmicutesandProteobacteriawere the major microbial phyla present across host species groups. Our analysis of alpha diversity showed that the transition to common environmental conditions significantly impacted host gut microbiome richness. In contrast, the change in host environment did not impact the community composition (i.e., beta diversity) of the gut microbiomes. Although not statistically significant, host ancestry may influence the microbiome composition more than host environment. Additional analyses suggest chloroplast 16S rRNA sequences accurately characterized host diets in captivity. In certain cases, 16S rRNA sequences can provide reliable characterization of habitat and dietary variation in wild birds. Although environment more strongly shapes microbiome richness and evenness, host ancestry may have a greater influence on the specific microbes present in the microbiome. 

(−)-Cylindrocyclophane A is a 22-membered C₂-symmetric [7.7]paracyclophane that bears bis-resorcinol functionality and six stereocenters. We report a synthetic strategy for (−)-cylindrocyclophane A that uses 10 C−H functionalization reactions, resulting in a streamlined route with high enantioselectivity and efficiency (17 steps). The use of chiral dirhodium tetracarboxylate catalysis enabled the C–H functionalization of primary and secondary positions, which was complemented by palladium-catalyzed C(sp²)–C(sp²) cross-couplings, resulting in the rapid formation of the macrocyclic core and all stereocenters with high regio-, diastereo-, and enantioselectivity. The use of a late-stage palladium-catalyzed fourfold C(sp²)–H acetoxylation installed the bis-resorcinol moieties. This research exemplifies how multilaboratory collaborations can produce substantial modernizations of complex total synthesis endeavors.