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Yucca moths ( Tegeticula and Parategeticula) are specialized pollinators of yucca plants, possessing unique, tentacle-like mouthparts used to actively collect pollen and deposit it onto the flowers of their hosts. The moths' larvae feed on the developing seeds and fruit tissue. First described in 1873, the yucca–yucca moth pollination system is now considered the archetypical example of a coevolved intimate mutualism. Research conducted over the past three decades has transformed our understanding of yucca moth diversity and host plant interactions. We summarize the current understanding of the diversity, ecology, and evolution of this group, review evidence for coevolution of the insects and their hosts, and describe how the nature of the interaction varies across evolutionary time and ecological contexts. Finally, we identify unresolved questions and areas for future research. 

Sex chromosomes have evolved hundreds of times across the flowering plant tree of life; their recent origins in some members of this clade can shed light on the early consequences of suppressed recombination, a crucial step in sex chromosome evolution. Amborella trichopoda, the sole species of a lineage that is sister to all other extant flowering plants, is dioecious with a young ZW sex determination system. Here we present a haplotype-resolved genome assembly, including highly contiguous assemblies of the Z and W chromosomes. We identify a ~3-megabase sex-determination region (SDR) captured in two strata that includes a ~300-kilobase inversion that is enriched with repetitive sequences and contains a homologue of the Arabidopsis METHYLTHIOADENOSINE NUCLEOSIDASE (MTN1-2) genes, which are known to be involved in fertility. However, the remainder of the SDR does not show patterns typically found in non-recombining SDRs, such as repeat accumulation and gene loss. These findings are consistent with the hypothesis that dioecy is derived in Amborella and the sex chromosome pair has not significantly degenerated. 

Over the last several years, chemists and engineers have identified the utility of using twin-screw extruders for performing large-scale organic chemistry mechanochemically. This equipment is convenient as it is familiar to several relevant industries for its use in formulation, and it is also well-equipped for temperature control and intense grinding of materials. However, the research and development scale of mechanochemistry is just like that of conventional synthesis: milligrams. These milligram-scale reactions are performed in batch-type reactors, often a ball mill. Commercially available ball mills do not have strict temperature control, limiting the information that can be obtained to inform the scale-up process reliably. This work uses an in-house modified, temperature-controlled, ball mill to bridge the knowledge gap regarding predictable, well-informed, economical, and reliable mechanochemical scale-ups. Included in this work is the first extrusion example of a nucleophilic aromatic substitution. 

Summary Myrothamnus flabellifoliais a dioecious resurrection plant endemic to southern Africa that has become an important model for understanding desiccation tolerance. Despite its ecological and medicinal significance, genomic and transcriptomic resources for the species are limited.We generated a chromosome‐level, haplotype‐resolved reference genome assembly and annotation forM. flabellifoliaand conducted transcriptomic profiling across a natural dehydration–rehydration time course in the field. Genome architecture and sex determination were characterized, and co‐expression network andcis‐regulatory element (CRE) enrichment analyses were used to investigate dynamic responses to desiccation.The 1.28‐Gb genome exhibits unusually consistent chromatin architecture with unique chromosome organization across highly divergent haplotypes. We identified an XY sexual system with a small sex‐determining region on Chromosome 8. Transcriptomic responses varied with dehydration severity, pointing to early suppression of growth, progressive activation of protective mechanisms, and subsequent return to homeostasis upon rehydration. Late embryogenesis abundant and early light‐induced protein transcripts were dynamically regulated and showed enrichment of abscisic acid and stress‐responsive CREs pointing toward conserved responses.Together, this study provides foundational resources for understanding the genomic architecture and reproductive biology ofM. flabellifoliaand offers new insights into the mechanisms of desiccation tolerance.