Studies using mobile eye tracking (MET) in art museums have provided valuable insights into the visitor experience. Findings suggest that this is strongly influenced by artwork features, exhibition design and visitor characteristics. To date, however, these empirical results have rarely been used to inform exhibition design. Here, we summarize recent MET research in art museums and discuss what these studies reveal about factors influencing the visitor experience. We argue that the field is characterized by an evaluation-implementation gap. Thus, the primary challenge is not the generation of new knowledge about visitor behaviour, but the translation of this knowledge into evidence-based interventions and broader institutional learning. We examine the factors contributing to this gap and outline strategies for strengthening collaboration between researchers and museum professionals. We conclude that MET offers considerable potential not only for understanding visitor behaviour, but also for evaluating exhibitions and related information materials under ecologically valid conditions. In the future it will be important to integrate museums' substantial professional expertise in designing exhibitions and visitor experiences, with methodological and data sharing practices more common among academic researchers. On the museum side this will require greater awareness of the applications of MET to visitor research, including empirical evaluation of museums' own initiatives. On the academic side, it requires collaboration with museum professionals at every stage of study design, from the formulation of research questions to the implementation of experiments and evaluation procedures.
This study explores how individuals perceive and respond to different types of visual art, particularly in terms of attention and emotional engagement. Art, whether created professionally for art galleries or commercially for mass consumption, can elicit diverse reactions depending on its complexity and intent. This research examines the differences in the brain's electrophysiological responses and likability ratings when viewing professional artworks (created for artistic expression) versus commercial paintings (created for profit). Using electroencephalography, participants' responses were recorded to images of abstract paints from the collections of museums (professional art) and images from the "Paintings" page of the online handicraft marketplace Etsy (commercial art). Two key event-related potential components were analyzed: the early posterior negativity (EPN), associated with attention, and the late positive potential (LPP), linked to emotional engagement. Likeability of each painting was rated on a 7-point likert-scale. The results showed that participants rated commercial paintings higher in likability and exhibited stronger LPP responses to them, indicating a greater emotional response. An additional detail is that the LPP difference between commercial and professional art shows a lateralization to the left hemisphere. Furthermore, and unexpectedly, the EPN is stronger for professional art. To confirm this surprising finding, this effect was replicated in a follow-up study. These results point to a distinct difference between how commercial and professional art is appreciated, though the process from perception to evaluation might be different and more complex than initially expected.
Change in the haploid chromosome number commonly generates reproductive isolation between diverging species. If changes to the haploid chromosome number (karyotype) most often generate new species, variation in the rate of chromosome number evolution is expected to predict variation in diversification rates. While this correlation has been supported in some plants, we know less about how the mode and tempo of karyotype change evolve. Methods to address the evolution of diversification and chromosome number transition rates are computationally expensive and analyses are typically restricted to small clades or avoided all together. We identify and describe variation in the mode and tempo of karyotype evolution (via dysploidy and polyploidy) in the Polypodiales-a species and karyotype-rich order of ferns-by extending the Chromosome Number and Hidden State-dependent Speciation and Extinction model (ChromoHiSSE) to include whole genome duplication. Using the extended ChromoHiSSE model we estimate rates of karyotype evolution across 962 leptosporangiate ferns of the Polypodiales. We recover two hidden modes of chromosome number evolution between which the rates of karyotype evolution differ by more than an order of magnitude. Our rate estimates and the stochastic mapping of these modes across fern evolution suggests lineages with high karyotype lability are less likely to persist in the long-term. These results reinforce the theory that modern fern diversity is shaped substantially by polyploid speciation but challenge the expectation that diversification rates are enhanced by karyotype-driven reproductive isolation.
The high incidence of polyploidy in crops could be explained if domestication involved the selection of polyploids (cytotypes with more than two sets of chromosomes). Ancestral horticulture could have targeted desirable traits including yield, robustness to stress or disease, rather than requiring knowledge of polyploidy itself. We find evidence for this process underway in enset (Ensete ventricosum, Musaceae), a highly resilient crop constituting the main staple for over 20 million people in Ethiopia, which is clonally propagated and cultivated for its starch-rich corm and pseudostem. Prior to this study, enset was thought to be exclusively diploid (2n = 2x = 18). Using a newly-assembled chromosome-scale reference genome, and sequence data from 723 wild and domesticated enset individuals from southwestern Ethiopia, we demonstrate that around 20% of cultivated enset clones are triploid. We show that triploidy has arisen multiple times independently, that the triploid lineages have been given distinct landrace names, and planted disproportionately frequently. Enset triploid clones also have a higher pseudostem volume than diploids on average. As well as providing evidence for enduring selection on triploids, our results reveal valuable genetic diversity captured by these triploid lines. They represent key resources for scientifically directed breeding of this major crop in the Ethiopian agrosystem, and could improve food security in Sub-Saharan Africa.
Continued chemical investigation of the sponge Agelas nakamurai led to the isolation of two new 2-bromopyrrole-2-aminoimidazoline alkaloids, 10E-dispacamide B (1) and (+)-10E-dispacamide D (2), together with their known 10Z-isomers, dispacamide B (3) and dispacamide D (4). The structures of the new metabolites were elucidated through comprehensive spectroscopic analyses, including 2D NMR experiments, along with the assistance of a single-crystal X-ray diffraction (SC-XRD) analysis of compound 3. Biological evaluation revealed that the newly identified alkaloids, 10E-dispacamide B (1) and (+)-10E-dispacamide D (2), exhibited stronger antibacterial activity than their corresponding 10Z-isomers, 3 and 4. In addition, a plausible biosynthetic pathway for the formation of both the 10E and 10Z isomers 1-4 from laughine was proposed. The occurrence of both 10E- and 10Z-isomers highlights the remarkable biosynthetic versatility of this sponge and underscores its potential as a valuable source of structurally diverse and biologically active natural products.
Mesozoic ecosystems differed from the present in the abundance of large-bodied herbivores that grew through several feeding envelopes, raising the question as to whether large-bodied adults were specialized for different resources than juveniles. Most investigations for ontogenetic resource partitioning in hadrosaurids show an ontogenetic trend towards tough plant material, but have been limited to 2D analyses of cranial shape, tooth wear, and occlusal shape. Here, we use 3D biomechanical modeling of an ontogenetic series of the hadrosaurid Corythosaurus casuarius to evaluate adaptations for resource partitioning. Results demonstrate adults had higher bite forces than juveniles and could process a wider range of materials, but jaw muscle size was negatively allometric, an uncommon trend that increased juvenile bite force and diet breadth relative to expectations for their size. Average stress and strain do not change ontogenetically, but there are changes in stress distribution. Crestless juvenile individuals exhibit a plesiomorphic stress distribution, whereas mature crested individuals experience low stress in the snout and higher stress in the braincase. This ontogenetic transition coincides with the expansion of the premaxillae and nasals to form the supracranial crest and is likely an evolutionary consequence of changes in cranial shape directing pressure away from this delicate structure.
Avian eggs reflect life-history trade-offs, and museum collections provide a valuable historical resource for examining how egg morphology and clutch size vary across species, space and time. However, shrikes (Laniidae), despite their ecological distinctiveness and broad distribution, still lack a comparative analysis of egg morphology and clutch size across species. Using historical oological collections spanning 1888-1973, we quantified inter- and intraspecific variation in egg morphology and clutch size in four shrike species: red-backed shrike (Lanius collurio), woodchat shrike (L. senator), lesser grey shrike (L. minor) and great grey shrike (L. excubitor). Across the historical collection period, clutch size increased over time only in the lesser grey shrike, whereas no robust temporal trend was detected in the other species. Where temporal trends in egg morphology occurred, size-related traits generally declined, whereas shape descriptors, including sphericity and shape index, remained comparatively stable. Among species, the great grey shrike laid the largest eggs and had the smallest clutches, while the lesser grey and woodchat shrikes had the largest clutches with smaller eggs, consistent with a broad size-number trade-off in reproductive allocation. Within species, spatial variation in egg-size traits was evident, particularly in the red-backed shrike and woodchat shrike, whereas evidence for a size-number relationship was weak. Overall, temporal change in shrike reproductive traits was limited and species-specific, while museum collections proved valuable for reconstructing long-term patterns of reproductive variation.
The incompleteness of the fossil record and the absence of genetic information limit our ability to understand ancient developmental processes and reconstruct their evolution. Gene expression patterns, physiological pathways, or cellular differentiation processes are rarely preserved, leaving major gaps in our understanding of developmental evolution. Here, we combine comparative and mathematical analyses to uncover an ancestral patterning mechanism underlying the specification of liverwort oil body cells, a synapomorphy of the lineage involved in anti-herbivory defense. We demonstrate that oil body cell homologs in fossils of the oldest known liverwort (Metzgeriothallus sharonae) exhibit spatial organization characteristic of lateral inhibition, including regular spacing and an over-representation of idioblasts. We show that a mechanism involving local activation and lateral inhibition reproduces the diversity of patterns observed in the fossils. Finally, we find that the same mechanism can explain oil body cell patterns in the distantly related liverworts Treubia lacunosa, Apotreubia nana, and Marchantia polymorpha, suggesting a deeply conserved mode of cell specification. Our findings illuminate the origin and diversification of oil body cells, underscoring their evolutionary significance for liverwort development and survival.
Butterflies have been a model system for studying the evolution of colour. This is partly due to their complex patterns that reflect human-visible (VIS) and ultraviolet (UV) light, which are perceived by conspecifics and predators. Many studies have sourced data from publicly available images, but most of these images only consider the visible spectrum of light. Including the UV spectrum is crucial for fully understanding the evolution of butterfly morphology and behavioural ecology. Here we provide standardized images (VIS and UV) of over 4 000 individuals from 16 communities of Australian butterflies. These communities represent different climates and urbanization levels spanning over 2 500 km. The dataset contains at least one individual of 125 different species from five families, constituting over one quarter of Australian butterfly diversity. In addition to photographs, we provide spectral measurements of butterfly wings for at least one individual of each species and sex, and Cytochrome Oxidase subunit 1 (CO1) sequences of 1 635 individuals. All these data are accessible in Zenodo and an associated R package simplifies the download of subsets of the database. This database will be of use to evolutionary biologists and ecologists interested in a broad range of topics related to phenotypic variation.
Genomic data from contemporary and historical samples often need to be coupled for evolutionary reconstructions of multitaxon complexes. However, the genetic data recovered from historical samples may result only in ultra-low coverage whole-genome sequences (ulcWGS; <0.15× depth), leading to inaccurate evolutionary inferences given a preponderance of missing data. Using the Galapagos giant tortoise radiation as a study system (Chelonoidis spp., composed of 13 extant and four extinct lineages), we assembled a novel methodological pipeline that removes potential noise introduced by the missing data and enhances the evolutionary signal from ulcWGS samples. We leveraged existing tools for phylogenomic placement (EPA-ng), population genomic structure (smartsnp) and admixture (Admixfrog, NGSadmix) to demonstrate that the evolutionary history of samples can be uncovered with sequencing depths as low as 0.008-0.139×. Importantly, these approaches do not use genotype imputation of the ulcWGS samples, which would require extensive reference datasets. Our application to two cases of extinct lineages of Galapagos giant tortoises, with and without references from the same lineage, demonstrates the general value of the approach. We confirm where the extinct lineages from San Cristóbal and Santa Fe islands fit into the Galapagos giant tortoise radiation, and that these lineages were evolutionarily distinct entities.
The genus Chiropodomys currently has six valid species recorded globally, widely distributed in Southeast Asia. No new Chiropodomys species has been described since the 1980s. In this study, a single specimen collected from Wanding, Yunnan Province, China, was analyzed using a combined methodology of morphological comparative analysis and molecular biology. The results show that the specimen is not only distinct from all known species of Chiropodomys in external morphology, but also the genetic distance between it and its close relatives is at least 13.06% (Cyt b) and 10.40% (COI). Based on these results, it is proved that the specimen represents a new Chiropodomys species: C. wandingensis sp. nov. Furthermore, based on this finding and in conjunction with literature data, a key to the species within the genus was compiled.
Tortoise beetles (Cassidinae s. str., Chrysomelidae, Coleoptera) compose a highly diverse group of insects, with most species found in Neotropical regions, such as the Brazilian Atlantic Forest, one of the most important hotspots in the world. Neotropical cassidines are known to typically display strong host specialization and distinct temporal patterns; however, host plants of most species are still unknown and very few studies have quantitatively investigated their temporal distribution. Here, we present a comprehensive list of tortoise beetle species for Serra do Japi, an Atlantic Forest mountain range, by comparing and combining data from 26 months of field work with data from previous samplings done in the same area. By collecting richness and abundance of adults for 12 consecutive months, as well as monthly mean temperature and precipitation, we also tested the correlation between assemblage and climatic factors. Our final list is composed of 71 cassidines species, with 11 new distribution records for the state of São Paulo and new host plant records for 36 of these species. We also show that the adults of this tortoise beetle assemblage present a seasonal pattern, similar to that of subtropical cassidines, which is significantly influenced by temperature variation, but not by precipitation. Our results highlight the importance of Serra do Japi as a conservation unit and contribute to a better understanding of several ecological aspects of Cassidinae s. str.
Factors varying along elevational gradients impose strong aerodynamic and physiological constraints on powered flight, yet the internal microanatomical variation associated with elevational context in animals under such conditions remains poorly understood. In hummingbirds, sustained hovering requires extreme muscular power output, making the pectoralis muscle a key tissue for evaluating anatomical variation associated with elevational context. We tested whether pectoralis microanatomy differed among hummingbirds sampled at three elevationally distinct sites spanning a ~1500 m gradient in the Colombian Andes. Using tissue morphometry of trichrome-stained transverse sections of the pectoralis, we measured collagen-rich interstitial extracellular matrix fraction as an anatomical proxy and quantified fiber-profile cross-sectional area, packing density, and size heterogeneity. Collagen-rich ECM fraction differed among sites, with the highest values at the mid-elevation site and the lowest values at the high-elevation site. Fiber-profile cross-sectional area tended to be lower and packing density higher at the high-elevation site, although site-level contrasts showed broad uncertainty. Because species identity and site could not be fully disentangled in this limited dataset, these patterns are interpreted as site-associated anatomical variation rather than definitive evidence of elevation-driven adaptation. These results suggest that hummingbird pectoralis microanatomy differs among sampled elevational contexts in a trait-specific manner, with the strongest evidence in fiber geometry. More broadly, our findings highlight that multiple components of muscle microarchitecture, including the extracellular matrix, are consistent with diffusion-related expectations rather than direct evidence of functional performance differences.
Light is a daily environmental exposure that can influence circadian timing, sleep, alertness, mood, and cognition, yet public health guidance still focuses mainly on optical-radiation hazards rather than healthy patterns of visible light and darkness. This policy brief translates recent evidence and expert consensus on the non-visual effects of ocular light exposure into public health guidance. The evidence supports a practical 24-h pattern: brighter light during the morning and daytime, lower light in the evening, and darkness or near-darkness during sleep. This principle should be communicated as general guidance rather than a universal dose, because responses vary with timing, intensity, spectrum, duration, prior light exposure, age, work schedules, health status, and geography. Public health organizations can communicate plain-language guidance, integrate light into workplaces, schools, healthcare, elder care, housing, and public buildings, align daylight messages with sun-safety advice, and support research, measurement, and melanopic labeling. Clear, proportionate guidance on light and darkness can help people and institutions structure daily environments to support circadian alignment, sleep, alertness, mental health, and wellbeing.
The outcomes of contact between closely-related species provide insights into the processes that influence divergence along the speciation continuum. We conducted a comparative genomic analysis of divergence between several taxa of Salvelinus fishes from the North Pacific that vary in estimated divergence times from 0.8 to 5.2 million years ago. We found a general increase in the extent of reproductive isolation, as assessed by the presence and kinds of hybrids produced in sympatry, and estimated divergence time. There was evidence of less effective gene flow between Salvelinus confluentus (bull trout) and S. malma lordi (Southern Dolly Varden) in sympatry than between the more recently diverged S. alpinus (Arctic char) and S. m. malma (Northern Dolly Varden) in sympatry. By contrast, although S. m. malma and S. m. lordi are estimated to have diverged from each other only slightly more recently than S. alpinus and S. malma (1.3-1.4 million years ago, respectively), the former produced hybrid swarms upon contact in two lakes while the latter pair showed pronounced, but incomplete, reproductive isolation while sympatric in three lakes. Genome wide assessments of divergence between pairs of taxa suggested that restriction of gene flow between each pair is widespread across the genome, consistent with advanced reproductive isolation between S. confluentus and S. m. lordi and S. alpinus and S. m. malma, but contrasts with an apparent lack of reproductive isolation between S. m. malma and S. m. lordi. We suggest that differences in reproductive ecology (or lack thereof) between pairs of taxa in sympatry likely contribute to variation in their position along the speciation continuum.
The importance of epigenetics in invasion biology is debated. In particular, the role of epigenetic mechanisms, such as DNA methylation, as potential drivers of rapid adaptation compensating for reduced genetic diversity remains an open question. Introduced to Australia 90 years ago, cane toads (Rhinella marina) are spreading at an ever-increasing rate. Across the invasion range, toads display overall low genetic diversity, yet paradoxically show high phenotypic variation in dispersal-related traits. Here, we use a common-garden experiment to investigate the role of DNA methylation in fostering rapid evolution in this system. We show that toads from newly established populations show distinct DNA methylation profiles to toads from long-colonized areas, particularly in genes putatively involved in dispersal. Epigenetic changes were strongly associated with genetic variation and often overlapped with transposable elements. Our results indicate that epigenetic changes following environmental perturbations have the potential to generate phenotypic variation at ecologically relevant traits in genetically depauperate invasive populations, their molecular interplay with gene activity being complex and probably context-dependent. This article is part of the theme issue 'Ecological epigenetics at the intersection of behaviour and life history variation in non-model animals'.
Despite the urgent need for conservation, reliable data on the distribution of fish species across countries and federal states is limited for both freshwater and marine habitats. The German Ichthyological Society (Gesellschaft für Ichthyologie e.V. or GfI) aims to compile fish distribution data with a focus on Germany (including its marine areas), Austria and the marine areas of the Netherlands and Denmark. These data are openly available on the "GfI-Fischartenatlas" web portal which serves as an information platform at the intersection of science, practice and environmental education, promoting the conservation of fish biodiversity and their habitats. The GfI-Fischartenatlas is a joint project of the GfI and the City University of Applied Sciences Bremen. It was developed in cooperation between the biology and computer science departments at the university. The IT basis for collecting, managing and presenting the data online is the "Biodiversity Warehouse" software architecture. The data are hosted by the Biodiversity Informatics Department at the Museum Koenig Bonn, which is part of the Leibniz Institute for the Analysis of Biodiversity Change (LIB). The GfI-Fischartenatlas consolidates fish distribution data from various cross-border sources into a unified platform. This includes both data collected specifically for the atlas and data integrated from other databases (in total n = 136,714, as of 13.03.2026). The data primary to the atlas are published as a dataset on the Global Biodiversity Information Facility (GBIF). This dataset (ABCD archive) contains occurrence records (n = 62,545) for 264 freshwater and marine fish species, derived from scientific and grey literature as well as citizen0science observations, covering 16 European countries (with a focus on Germany and Austria).
Anthropogenic hybridization with domesticated relatives is reshaping the genetics of many wild species, yet reconstructing how and when such admixture unfolded is rarely possible without long-term sampling. Here, we use hundreds of museum samples representing North American mallard (Anas platyrhynchos) populations dating from 1800 to today to reconstruct the tempo and mode of interactions between wild-origin birds and captive-bred game-farm mallards that have undergone sustained stocking since the early 20th century. We confirm that game-farm mallard ancestry first appeared in wild populations in the 1910s-1920s, coincident with releases that were first reported in North America, and that its spread occurred through multiple bouts of introgression rather than a single event or steady, additive accumulation. This admixture has been markedly uneven across flyways: the Pacific and Central Flyways have remained largely genetically wild, whereas the Atlantic and Mississippi Flyways, particularly the Great Lakes Region and northeastern Atlantic coast, where annual releases have long supplemented declining mallard populations, show sustained, increasing game-farm ancestry consistent with a hybrid swarm scenario in eastern North America. Furthermore, we find that genetic diversity is reduced among more admixed ancestry groups and that FHBD-based inbreeding coefficients increase with the proportion of game-farm mallard ancestry. Together, we provide a temporally and spatially resolved account of anthropogenic hybridization in a wild species and indicate that the genetic integrity, or "wildness," of North American mallards is being actively eroded and artificially sustained by continued game-farm mallard releases, with direct implications for management of captive-breeding and stocking programs worldwide.
Two new species of the leafhopper genus Eurhadina Haupt, 1929 (Typhlocybinae, Typhlocybini) from China are described and illustrated: E. (Eurhadina) cervina Tang, sp. nov. and E. (Eurhadina) dashuensis Tang, sp. nov. A key to the subgenera of Eurhadina, a key to the Chinese species of E. (Eurhadina) Haupt, 1929, and an appendix with a checklist of Chinese Eurhadina species are provided. The subgenus and species E. (Zhihadina) sinica Yang & Li, 1991 are treated as nomen dubia and incertae sedis in Typhlocybinae. Diagnoses of the recognized subgenera are provided, and figures of E. (Singhardina) rubrocorona Cai & Kuoh, 1993 are given for comparison with the nominate subgenus.
Caudal vertebrae of caenophidian snakes are characterized by the presence of paired haemapophyses-a pattern observed from the earliest-diverging acrochordid lineage to the most derived viperids, and documented in the fossil record from the Late Cretaceous onward, including the basalmost known extinct caenophidian forms. Using micro-computed tomography scanning, we document an extraordinary deviation from this pattern. We examined five species across three genera of the Asian family Calamariidae (Reed snakes) and demonstrate that they, uniquely among Colubroidea, lack haemapophyses throughout the caudal vertebral series, possessing instead prominent haemal keels-a condition that represents a novel diagnostic feature for Calamariidae. This simplification of vertebral morphology, coupled with an extremely reduced number of caudal vertebrae, likely correlates with the fossorial lifestyle characteristic of this snake family. Furthermore, we identify and illustrate unexpected modifications of subcentral structures in certain other caenophidian taxa, that is, a pareid and several distantly related elapoid species. Our findings underscore the significant taxonomic and diagnostic value of caudal vertebral morphology, a skeletal element that has been largely overlooked.