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Museum collections remain essential scientific resources, especially when revisited using modern analytical techniques. In an interdisciplinary study, we examined the overlooked amber collection of Johann Wolfgang von Goethe (1749–1832), polymath and pioneer of art and natural science. Using synchrotron-based micro-computed tomography (SR-µ-CT), we identified a fossil ant from Baltic amber (Eocene ~ 47–34 Ma) in Goethe’s collections. The specimen is assigned to †Ctenobethylus goepperti (Mayr in Die Ameisen des Baltischen Bernsteins. Beiträge zur Naturkunde Preussens, 1868), which we redescribe and re-diagnose, proposing †Eldermyrmex exsectus Dubovikoff et Dlussky, 2019 as its junior synonym (syn. nov., comb. nov.). We further infer a potential sister-group relationship with the extant genus Liometopum Mayr, 1861, suggesting that †C. goepperti may have been a dominant arboreal species in warm-temperate coniferous forests, a scenario which is supported by its abundance in Baltic amber. Critically, our results document endoskeletal structures in a Cenozoic fossil ant, underscoring both the morphological value of historical collections and the lasting scientific legacy of Goethe’s naturalist vision.

Quantifying animal movements is necessary for answering a wide array of research questions in ecology and conservation biology. Consequently, ecologists have made considerable efforts to identify the best way to estimate an animal's home range, and many methods of estimating home ranges have arisen over the past half a century. Most of these methods fall into two distinct categories of estimators that have only recently been described in statistical detail: those that measure range distributions (methods such as kernel density estimation that quantify the long-run behavior of a movement process that features restricted space use) and those that measure occurrence distributions (methods such as Brownian bridge movement models and the Correlated Random Walk Library that quantify uncertainty in an animal movement path during a specific period of observation). In this paper, we use theory, simulations, and empirical analysis to demonstrate the importance of appropriately using these two categories of distributions and their estimators. Conflating range and occurrence distributions can have serious consequences for ecological inference and conservation practice. For example, in most situations, home ranges estimated using estimators of occurrence distributions are too small, and this problem is exacerbated by ongoing improvements in tracking technology that enable more frequent and more accurate data on animal movements. We encourage researchers to use estimators of range distributions to quantify home ranges and estimators of occurrence distributions to answer other questions in movement ecology, such as when and where an animal crossed a linear feature, visited a location of interest, or interacted with other animals.

The latitudinal diversity gradient (LDG) designates the increase in species richness toward the tropics. While geological and climatic changes are recognized as key drivers, the precise factors and their relative contributions to species richness gradients remain debated. Using a spatially explicit eco-evolutionary model, we simulate diversification over 125 million years. We validate the model with empirical mammalian richness patterns, and uncover a pivotal role of paleoclimate and paleogeography. This approach allows us to investigate both the mechanisms driving the LDG and space and time variations in species diversification rates across dynamic landscapes integrating changes in tectonic, climatic and surface processes. We show how scale-dependent surface processes are a key driver of regional diversity patterns and how LDG can emerge under a wide range of eco-evolutionary scenarios. Plate tectonics and the subsequent enduring uneven distribution of land masses within the North and South hemispheres imprinted an asymmetric pattern of species diversification rates, primarily shaped by paleoclimate and paleogeography and only to a lesser extent by surface processes. Our simulations also indicate that the LDG has persisted since the Cretaceous, steepened and stabilized from the early Cenozoic on. The modeled scenarios depict that species primarily originate in the tropics and disperse toward the poles without losing their tropical presence. The tropics not only served as a cradle, fostering the origination of new species, but also as a museum, preserving biodiversity over deep time.

The study of ant morphology is advancing through parallel insights provided by phylogenomics-which provides a statistically robust basis for comparison and evolutionary inference-and phenomics via the application of microcomputed tomography (µ-CT) for the efficient and precise documentation of anatomy. The information provided by µ-CT is complex and rich, allowing for the quantification of geometry and biomechanically relevant variables, as well as comparative morphology via 3D rendering. Recently, the complete musculature of the thorax, propodeum, and legs was documented for the first time in an ant (Formica rufa L.). Here, we provide a detailed comparison of those findings for Protanilla lini Terayama, 2009 (Leptanillinae), representing the Leptanillomorpha, a clade putatively sister to all other living ants. Using µ-CT, computer-based reconstruction, and scanning electron microscopy (SEM), we observe a novel series of morphological features that are plausibly part of the groundplan of the Formicidae. For several of these features, we provide new anatomical concepts and terms, with special discussion of the pronotum, promesothoracic articulation, and metapleural gland region. We also observe characters that are likely correlated with specialized subterranean habits, including the increased flexibility of the promesothoracic articulation, the slender shape of the mesosoma, a simplified vestiture of short setae, and depigmentation. Mesosomal skeletomusculature in P. lini appears to be plesiomorphic relative to other Leptanillomorpha, resembling the putative ancestral condition for the Formicidae. An exception lies in the lack of cervical muscle (Idlm1) in Protanilla that is present in almost all other insects for which this character has been sampled. With this study of P. lini, we are one step closer to realizing the complete set of defining features and variation of the ant mesosoma.

Covering: up to April 2024Terpenoids represent the largest and structurally most diverse class of natural products. According to textbook knowledge, this diversity arises from a two-step biosynthetic process: first, terpene cyclases generate a vast array of mono- and polycyclic hydrocarbon scaffolds with multiple stereocenters from a limited set of achiral precursors, a process extensively studied over the past two decades. Subsequently, tailoring enzymes further modify these complex scaffolds through regio- and stereocontrolled oxidation and other functionalization reactions, a topic of increasing interest in recent years. The resulting highly functionalized terpenoids exhibit a broad spectrum of unique biological activities, making them promising candidates for drug development. Recent advances in genome sequencing technologies along with the development and application of sophisticated genome mining tools have revealed bacteria as a largely untapped resource for the discovery of complex terpenoids. Functional characterization of a limited number of bacterial terpenoid biosynthetic pathways, combined with in-depth mechanistic studies of key enzymes, has begun to reveal the versatility of bacterial enzymatic processes involved in terpenoid modification. In this review, we examine the various tailoring reactions leading to complex bacterial terpenoids. We first discuss canonical terpene-modifying enzymes, that catalyze the functionalization of unactivated C-H bonds, incorporation of diverse functional groups, and oxidative and non-oxidative rearrangements. We then explore non-canonical terpene-modifying enzymes that facilitate oxidative rearrangement, cyclization, isomerization, and dimerization reactions. The increasing number of characterized tailoring enzymes that participate in terpene hydrocarbon scaffold fomation, rather than merely decorating pre-formed scaffolds suggests that a re-evaluation of the traditional two-phase model for terpenoid biosynthesis might be warranted. Finally, we address the potential and challenges of mining bacterial genomes to identify terpene biosynthetic gene clusters and expand the bacterial terpene biosynthetic and chemical space.

Agricultural landscapes provide material, nonmaterial, and regulating contributions that affect human well-being (nature's contributions to people, NCP). The responses of these NCP to land-use patterns depend on supporting biota with different habitat requirements, generating trade-offs and synergies. Predictions from spatially explicit modeling of NCP trade-offs and synergies could inform land-use decisions, but these do not typically account for the effects of land-use patterns on the movement of NCP-providing species, nor for interactions among NCP providers. To explore spatial trade-offs and synergies in eight indicators of NCP, we used Bayesian models that allow for interactions among land uses and among NCP using data from 150 grassland sites across rural Germany. We found that spatial arrangements of forest and open habitat influenced many beneficial NCP: acoustic diversity, birdwatching potential, natural enemy abundance, and pollination. In particular, the amount and proximity of land uses in the surrounding landscape, especially forest and open habitat, drove the supply of most NCP. However, detrimental NCP provided by smaller-bodied taxa (herbivory and pathogen infection) responded weakly to landscape factors. Multiple NCP provided by a given taxon responded differently to their surrounding landscape (e.g., bird-provided beneficial caterpillar predation and detrimental seed predation), leading to trade-offs and synergies among NCP over short distances. These were caused by different rates and directions of response to amount and location of land uses. Resulting spatial predictions revealed that the ratio of beneficial to detrimental NCP was maximized in areas with a high (≥95%) area of grassland or mixed forest-grassland (70:30%), rather than purely forest-dominated areas. This suggests promoting seminatural vegetation in agricultural landscapes to provide greater-than-additive benefits to net NCP supply.

Microorganisms synthesize small bioactive compounds through their secondary or specialized metabolism. Those compounds play an important role in microbial interactions and soil health, but are also crucial for the development of pharmaceuticals or agrochemicals. Over the past decades, advancements in genome sequencing have enabled the identification of large numbers of biosynthetic gene clusters directly from microbial genomes. Since its inception in 2011, antiSMASH (https://antismash.secondarymetabolites.org/), has become the leading tool for detecting and characterizing these gene clusters in bacteria and fungi. This paper introduces version 8 of antiSMASH, which has increased the number of detectable cluster types from 81 to 101, and has improved analysis support for terpenoids and tailoring enzymes, as well as improvements in the analysis of modular enzymes like polyketide synthases and nonribosomal peptide synthetases. These modifications keep antiSMASH up-to-date with developments in the field and extend its overall predictive capabilities for natural product genome mining.

The American mink Neogale vison is native to North America and was introduced to Europe at the beginning of the twentieth century. Although N. vison is not yet listed as an invasive species in Europe, it is suspected of having negative impacts on native ecosystems. The native European mink Mustela lutreola is considered highly endangered in Europe and the population is continuously declining. It is assumed that the American mink is having an impact on the remaining populations. 50 American mink from Central Europe (Hesse/Germany) were comprehensively examined parasitologically through necropsy and fecal analysis. Further, an extensive literature search on parasitization was done to compare the American and European mink in Europe. Nine parasite species (two ecto- and seven endoparasites) could be identified parasitizing N. vison in this study. Through necropsy, the highest prevalence was achieved by Ixodes ticks with > 65.0%, the most common endoparasite was Isthmiophiora melis with 24.0%. Capillaria putorii and C. aerophila were detected in American mink in Germany for the first time by this investigation. The literature search resulted in the identification of 65 parasite species in twelve European countries for N. vison and 37 parasite species in six European countries for M. lutreola. Neogale vison is superior in body size, establishing well in Europe, appears to carry a more diverse parasite fauna and seems to be in direct competition to the disappearing European mink.

Bacterial chromosomes are spatiotemporally organized and sensitive to environmental changes. However, the mechanisms underlying chromosome configuration and reorganization are not fully understood. Here, we use single-molecule localization microscopy and live-cell imaging to show that the Escherichia coli nucleoid adopts a condensed, membrane-proximal configuration during rapid growth. Drug treatment induces a rapid collapse of the nucleoid from an apparently membrane-bound state within 10 min of halting transcription and translation. This hints toward an active role of transertion (coupled transcription, translation, and membrane insertion) in nucleoid organization, while cell wall synthesis inhibitors only affect nucleoid organization during morphological changes. Further, we provide evidence that the nucleoid spatially correlates with elongasomes in unperturbed cells, suggesting that large membrane-bound complexes might be hotspots for transertion. The observed correlation diminishes in cells with changed cell geometry or upon inhibition of protein biosynthesis. Replication inhibition experiments, as well as multi-drug treatments highlight the role of entropic effects and transcription in nucleoid condensation and positioning. Thus, our results indicate that transcription and translation, possibly in the context of transertion, act as a principal organizer of the bacterial nucleoid, and show that an altered metabolic state and antibiotic treatment lead to major changes in the spatial organization of the nucleoid.

Protection against pathogens is a major function of the gut microbiota. Although bacterial natural products have emerged as crucial components of host-microbiota interactions, their exact role in microbiota-mediated protection is largely unexplored. We addressed this knowledge gap with the nematode Caenorhabditis elegans and its microbiota isolate Pseudomonas fluorescens MYb115 that is known to protect against Bacillus thuringiensis (Bt) infection. We find that MYb115-mediated protection depends on sphingolipids (SLs) that are derived from an iterative type I polyketide synthase (PKS) cluster PfSgaAB, thereby revealing a non-canonical pathway for the production of bacterial SLs as secondary metabolites. SL production is common in eukaryotes but was thought to be limited to a few bacterial phyla that encode the serine palmitoyltransferase (SPT) enzyme, which catalyses the initial step in SL synthesis. We demonstrate that PfSgaB encodes a pyridoxal 5'-phosphate-dependent alpha-oxoamine synthase with SPT activity, and find homologous putative PKS clusters present across host-associated bacteria that are so far unknown SL producers. Moreover, we provide evidence that MYb115-derived SLs affect C. elegans defence against Bt infection by altering SL metabolism in the nematode host. This work establishes SLs as structural outputs of bacterial PKS and highlights the role of microbiota-derived SLs in host protection against pathogens.

Azetidine-2-carboxylic acid (AZE) is a long-known plant metabolite. Recently, AZE synthases have been identified in bacterial natural product pathways involving non-ribosomal peptide synthetases. AZE synthases catalyse the intramolecular 4-exo-tet cyclisation of S-adenosylmethionine (SAM), yielding a highly strained heterocycle. Here, we combine structural and biochemical analyses with quantum mechanical calculations and mutagenesis studies to reveal catalytic insights into AZE synthases. The cyclisation of SAM is facilitated by an exceptional substrate conformation and supported by desolvation effects as well as cation-π interactions. In addition, we uncover related SAM lyases in diverse bacterial phyla, suggesting a wider prevalence of AZE-containing metabolites than previously expected. To explore the potential of AZE as a proline mimic in combinatorial biosynthesis, we introduce an AZE synthase into the pyrrolizixenamide pathway and thereby engineer analogues of azabicyclenes. Taken together, our findings provide a molecular framework to understand and exploit SAM-dependent cyclisation reactions.

Caring for newborn offspring hampers resource acquisition of mammalian females, curbing their ability to meet the high energy expenditure of early lactation. Newborns are particularly vulnerable, and, among the large herbivores, ungulates have evolved a continuum of neonatal antipredator tactics, ranging from immobile hider (such as roe deer fawns or impala calves) to highly mobile follower offspring (such as reindeer calves or chamois kids). How these tactics constrain female movements around parturition is unknown, particularly within the current context of increasing habitat fragmentation and earlier plant phenology caused by global warming. Here, using a comparative analysis across 54 populations of 23 species of large herbivores from 5 ungulate families (Bovidae, Cervidae, Equidae, Antilocapridae and Giraffidae), we show that mothers adjust their movements to variation in resource productivity and heterogeneity according to their offspring's neonatal tactic. Mothers with hider offspring are unable to exploit environments where the variability of resources occurs at a broad scale, which might alter resource allocation compared with mothers with follower offspring. Our findings reveal that the overlooked neonatal tactic plays a key role for predicting how species are coping with environmental variation.

Cryptic species complexes-genetically divergent lineages with similar phenotypes may appear cryptic not due to true similarity, but because high within-species morphological variation masks interspecies differences, particularly in heterogeneous environments. This study tests whether such lineages exhibit morphological convergence across similar environmental gradients or context-dependent divergence, challenging their cryptic status. We propose a theoretical framework to assess phenotypic differentiation and apply it using the amphipod complex Gammarus roeselii, which diversified in the Balkan Peninsula before one lineage expanded into Central Europe. We examined five lineages across similar environmental gradients to evaluate their phenotypic divergence. Our findings confirmed their cryptic status. However, phenotypic differentiation along environmental gradients revealed MOTU-specific adaptive trajectories: traits under strong selection (e.g., anti-predator defences) showed convergent responses, while morphological (e.g., body length) and physiological traits (e.g., gill area) diverged, likely due to local selection. Some MOTUs exhibited distinct, partially divergent sexual dimorphism, suggesting varied reproductive or ecological strategies within cryptic lineages. Phenotypic variation was greater within than between MOTUs, reinforcing their cryptic status and revealing strong local adaptive responses. This complex exemplifies how adaptive divergence and biogeographic history jointly shape biodiversity, with morphological stasis despite genetic and ecological differentiation exposing hidden speciation and environmental responses.

Conservation translocations are increasingly used in species' recovery. Their success often depends upon maintaining or restoring survival-relevant behaviour, which is socially learned in many animals. A lack of species- or population-appropriate learning can lead to the loss of adaptive behaviour, increasing the likelihood of negative human interactions and compromising animals' ability to migrate, exploit resources, avoid predators, integrate into wild populations, reproduce and survive. When applied well, behavioural tools can address deficiencies in socially learned behaviours and boost survival. However, their use has been uneven between species and translocation programmes, and behaviour commonly contributes to translocation failure. Critically, current international guidance (e.g. the International Union for Conservation of Nature's translocation guidelines) does not directly discuss social learning or its facilitation. We argue that linking knowledge about social learning to appropriate translocation strategies will enhance guidance and direct future research. We offer a framework for incorporating animal social learning into translocation planning, implementation, monitoring and evaluation across wild and captive settings. Our recommendations consider barriers practitioners face in contending with logistics, time constraints and intervention cost. We emphasize that stronger links between researchers, translocation practitioners and wildlife agencies would increase support for social learning research, and improve the perceived relevance and feasibility of facilitating social learning.This article is part of the theme issue 'Animal culture: conservation in a changing world'.

The polyketide specialized metabolites of bacteria are attractive targets for generating analogues, with the goal of improving their pharmaceutical properties. Here, we aimed to produce C-26 derivatives of the giant anti-cancer stambomycin macrolides using a mutasynthesis approach, as this position has been shown previously to directly impact bioactivity. For this, we leveraged the intrinsically broad specificity of the acyl transferase domain (AT12) of the modular polyketide synthase (PKS), which is responsible for the alkyl branching functionality at this position. Feeding of a panel of synthetic and commercially available dicarboxylic acid 'mutasynthons' to an engineered strain of Streptomyces ambofaciens (Sa) deficient in synthesis of the native α-carboxyacyl-CoA extender units, resulted in six new series of stambomycin derivatives as judged by LC-HRMS and NMR. Notably, the highest product yields were observed for substrates which were only poorly accepted when AT12 was transplanted into a different PKS module, suggesting a critical role for domain context in the overall functioning of PKS proteins. We also demonstrate the superiority of this mutasynthesis approach - both in terms of absolute titers and yields relative to the parental compounds - in comparison to the alternative precursor-directed strategy in which monoacid building blocks are supplied to the wild type strain. We further identify a malonyl-CoA synthetase, MatB_Sa, with specificity distinct from previously described promiscuous enzymes, making it a useful addition to a mutasynthesis toolbox for generating atypical, CoA activated extender units. Finally, we show that two of the obtained (deoxy)-butyl-stambomycins exhibit antibacterial and antiproliferative activities similar to the parental stambomycins, while an unexpected butyl-demethyl congener is less potent. Overall, this works confirms the interest of biosynthetic pathways which combine a dedicated route to extender unit synthesis and a broad specificity AT domain for producing bioactive derivatives of fully-elaborated complex polyketides.

The early (approx. 1650-540 Ma) history of eukaryotes was punctuated by several major-but enigmatic-environmental perturbations that potentially influenced the evolution of the Proterozoic biosphere, and the changing structure of Earth systems leading up to the Cambrian Explosion of animals. Reconstructing the manner in which eukaryotes responded to these events represents an innovative lens with which to understand what these perturbations actually represent, as well as the links between geosphere and biosphere during a critical period in eukaryotic evolution. In this study, we analyse organic-walled microfossil size and morphology across the Ediacaran-Cambrian transition. We illustrate that the decrease in vesicle diameter-previously shown to occur across the Ediacaran-Cambrian transition-began in the Ediacaran following the 'Shuram' carbon isotope excursion. This size decrease was accompanied by an increase in relative process length across the Ediacaran-Cambrian transition, which has not been previously quantified. Finally, following the 'Shuram' excursion, we illustrate a sustained shift in overall morphology. This shift in morphology may have been driven by nutrient stress enhanced by environmental change and/or the increased importance of planktonic lifestyles, highlighting the expansion of microbial eukaryotes into the plankton as a key step in the establishment of modern marine food webs.

The eXchange Unit between Thiolation domains approach and artificial intelligence (AI)-driven tools like Synthetic Intelligence are transforming nonribosomal peptide synthetase and polyketide synthase engineering, enabling the creation of novel bioactive compounds that address critical challenges like antibiotic resistance and cancer. These innovations expand chemical space and optimize biosynthetic pathways, offering precise and scalable therapeutic solutions. Collaboration across synthetic biology, AI, and clinical research is essential to translating these breakthroughs into next-generation treatments and revolutionizing drug discovery and patient care.

Ferrissia californica (Rowell, 1863) (Gastropoda: Hygrophila: Planorbidae) is a globally distributed freshwater limpet native to North America. Based on the specimens collected in Georgia, we aimed to sequence and annotate the mitochondrial genome of F. californica for the first time. The mt-genome spans 13526 bp containing 13 protein-coding, 2 ribosomal RNA, and 22 transfer RNA genes. Comparisons with the mitochondrial genomes of other gastropod molluscs revealed differences in gene organization. A phylogenetic reconstruction based on 12 protein-coding genes of several representatives from the Planorbidae and Limnaeidae families placed F. californica and Laevapex fuscus (C. B. Adams, 1840) as sister taxa.

Megalothorax Willem, 1900 is a genus of Collembola that comprises 36 species to date. For a long time, its diversity was overlooked, but recent integrative taxonomic works allowed us to understand better their seemingly cryptic diversity. Among the oddities of the genus are the so-called "nosed" species, i.e. species equipped with a frontal cuticular process, an unusual trait for Collembola. In this work, we describe a new "nosed" species from the north of European part of Russia and redescribe the first known "nosed" species: Megalothorax sanctistephani Christian, 1998. This species is known only from peculiar places: initially the catacombs of a cathedral in Vienna, and our new findings in underground tunnel in Paris and Botanical Garden of Kaliningrad. We also used long-read sequencing to obtain new DNA data for "nosed" species of Collembola. We investigated the evolution of the "nose" using molecular and morphological phylogeny approaches. This evolution remained unclear, as molecular and morphological data are conflicting on this specific point. The "nose" may have been acquired a single time, then lost secondarily in some species; or have been acquired independently several times.