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How do you solve a problem like Màiri?:nineteenth-century Gaelic song, rewilding, and audience creation
No full textMàiri Mhòr nan Oran (Mary MacPherson, Big Mary of the Songs) was the most influential Scottish Gaelic songwriter/poet of the late nineteenth century and one of the most high-profile land and language activists of the period. This article examines some of her (incredibly popular) work and the manner in which she weaves contemporary comment, biography, and a reworking of traditional tunes and motifs in a way designed to have social and political impact. It discusses some of her most well-known songs alongside those which have rarely been translated into English, and places these alongside the work of her contemporary Mary MacKellar (bàrd of the Gaelic Society of Inverness), and within the context of debates in the 1870s and 1880s about the future of the Gaelic language and the political campaign for greater rights for crofting communities — and then asks what, if anything, can be learned from this for contemporary debates about land use in the Highlands of Scotland
Russian Soul and the Imperialist Mindset
No full textShpirti rus apo mendёsia imperialiste? [Russian Soul and the Imperialist Mindset] (translated from the English into Albanian by Bardhyl Selimi) (pp. 44-49). 2025. DULINGVA BULTENO DE LA ALBANA ESPERANTO – INSTITUTO / Buletini dygjuhësh i Institutit Shqiptar të Esperantos. No. 186, (maj-qershor 2025, majo-junio 2025
Russia has been working on creating drones that ‘call home’, go undercover and start fires. Here’s how they work
No full textGlobal tracking of marine megafauna space use reveals how to achieve conservation targets
No full textThe recent Kunming-Montreal Global Biodiversity Framework (GBF) sets ambitious goals but no clear pathway for how zero loss of important biodiversity areas and halting human-induced extinction of threatened species will be achieved. We assembled a multi-taxa tracking dataset (11 million geopositions from 15,845 tracked individuals across 121 species) to provide a global assessment of space use of highly mobile marine megafauna, showing that 6300Target 3) will be insufficient for marine megafauna’s effective conservation, leaving important areas exposed to major anthropogenic threats. Coupling area protection with mitigation strategies (e.g., fishing regulation, wildlife-traffic separation) will be essential to reach international goals and conserve biodiversity. Many large marine animals are threatened with extinction. To address this problem, the Kunming-Montreal Global Biodiversity Framework has set a goal of protecting, conserving, and managing at least 30s oceans. However, the effectiveness of area-based conservation may be limited for highly mobile marine species, especially when there is limited understanding of the spatial and temporal dynamics of animal movement in the oceans. Sequeira et al. compiled tracking data from thousands of large marine vertebrates representing more than 100 species and identified important migratory corridors and areas where many species reside (see the Perspective by Gerber and Davis). Their findings show hotspots of movement and reveal that 30 particularly considering the distribution of threats to biodiversity. —Bianca Lope
Widespread and diverging patterns of change in local phylogenetic diversity
No full textAim: Ecosystems are witnessing drastic changes in biodiversity worldwide. However, it is still unclear whether changes in phylogenetic diversity—a measure of the evolutionary relationships among species—reflect observed changes in species richness. Specifically, we ask whether changes in local phylogenetic diversity correlate with changes in species richness and examine if major taxonomic groups show diverging trends. Location: Global. Methods: We estimate how local phylogenetic diversity has changed compared to species richness and whether there were diverging patterns across taxonomic groups. We use a database of compiled assemblage time series from around the world, BioTIME. We use assemblage total evolutionary history (Faith's phylogenetic diversity; PD) as well as average relatedness (mean pairwise distance and mean nearest taxon distance; MPD and MNTD, respectively) as measures of phylogenetic diversity and report taxon-level and assemblage-level posterior slope estimates from a Bayesian hierarchical model. We report trends in four major taxonomic groups: fish, birds, terrestrial mammals and terrestrial plants. Results: We found strong evidence of widespread increases in MPD across fish and bird assemblages, reflecting decreases in average relatedness and strong evidence of a decrease of MPD in mammals, indicating the opposite. Conversely, we did not find consistent directional change in MNTD, though null average trends included notable positive and negative trends across studies and regions. We also found moderate evidence that SR and PD were increasing in fish assemblages, while they were decreasing in mammals. Main Conclusions: Our findings suggest that changes in species composition are significantly altering the evolutionary makeup of assemblages at the local scale and that overall patterns diverge within and across taxonomic groups. We suggest potential drivers of these changes but highlight that our results are more generalisable for fish and birds than for mammals and plants, given the variation in geographical coverage and sample size
EPPA numbers of graphs
No full textIf G is a graph, A and B its induced subgraphs, and f : A→B an isomorphism, we say that f is a partial automorphism of G. In 1992, Hrushovski proved that graphs have the extension property for partial automorphisms (EPPA, also called the Hrushovski property), that is, for every finite graph G there is a finite graph H, an EPPA-witness for G, such that G is an induced subgraph of H and every partial automorphism of G extends to an automorphism of H. The EPPA number of a graph G, denoted by eppa(G), is the smallest number of vertices of an EPPA-witness for G, and we put eppa(n)=max{eppa(G) : |G| = n}. In this note we review the state of the area, prove several lower bounds (in particular, we show that eppa(n) ≥ 2n/sqrt(n), thereby identifying the correct base of the exponential) and pose many open questions. We also briefly discuss EPPA numbers of hypergraphs, directed graphs, and Kk-free graphs.<br/
Perspective-assisted prototype-based learning for semi-supervised crowd counting
No full textTo alleviate the burden of labeling data to train crowd counting models, we propose a prototype-based learning approach for semi-supervised crowd counting with an embeded understanding of perspective. Our key idea is that image patches with the same density of people are likely to exhibit coherent appearance changes under similar perspective distortion, but differ significantly under varying distortions. Motivated by this observation, we construct multiple prototypes for each density level to capture variations in perspective. For labeled data, the prototype-based learning assists the regression task by regularizing the feature space and modeling the relationships within and across different density levels. For unlabeled data, the learnt perspective-embedded prototypes enhance differentiation between samples of the same density levels, allowing for a more nuanced assessment of the predictions. By incorporating regression results, we categorize unlabeled samples as reliable or unreliable, applying tailored consistency learning strategies to enhance model accuracy and generalization. Since the perspective information is often unavailable, we propose a novel pseudo-label assigner based on perspective self-organization which requires no additional annotations and assigns image regions to distinct spatial density groups, which mainly reflect the differences in average density among regions. Extensive experiments on four crowd counting benchmarks demonstrate the effectiveness of our approach
Graph products of residually finite monoids are residually finite
No full textWe show that any graph product of residually finite monoids is residually finite. As a special case we obtain that any free product of residually finite monoids is residually finite. The corresponding results for graph products of semigroups follow
