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Hypothesis Description: Darwin’s Naturalisation Hypothesis
No full textIn this contribution of the Hypothesis Description series, we provide an overview of one of the longest-standing hypotheses in invasion science: Darwin's naturalisation hypothesis. We present a brief summary of past definitions and propose the revised definition “high phylogenetic distance between non-native species and the recipient community increases invasion success”. This formulation follows the basic form ‘subject – relationship – object’, enabling clarity for future research and computational applications in invasion biology. We also provide formalised definitions for previous formulations of the hypothesis and identify both related and opposite hypotheses to Darwin’s naturalisation hypothesis
Southernmost record of Liparis montagui (Donovan, 1804) (Perciformes, Liparidae) in European waters (central Portugal), with genetic validation
No full textIn January 2022, the presence of adult Liparis montagui (Donovan, 1804) was documented at its southernmost point along the west coast of Portugal. The species was identified through both morphological and genetic barcoding analyses. This observation, part of an ongoing long-term coastal survey, suggests that L. montagui may be a transient species, influenced by complex climate and oceanic interactions along the western Iberian coast. This finding stresses the importance of long-term ecological studies and regular field surveys in understanding species distribution and the effects of climate change on marine biodiversity
Transfusion frequency, ferritin, and carotid intima media thickness in transfusion-dependent thalassemia patients
No full textIntroduction: The carotid tunica intima-media thickness (cIMT) is an early marker of atherosclerosis and associated with an increased risk of cardiovascular diseases. Endothelial dysfunction also contributed with the increased cardiovascular risk in thalassemia caused by iron accumulation, reduced nitric oxide, and increased lipid peroxidation. Studies about atherosclerosis markers in thalassemia patients show inconsistent results. Aim: This research assesses cIMT in transfusion-dependent thalassemia patients and examines its relationship with clinical and laboratory parameters. Materials and methods: This was a cross-sectional study that was conducted from March to May 2024, in the Therapy and Thalassemia Clinics, Universitas Indonesia Hospital. Ultrasound cIMT measurements were recorded for both the left and right distal common carotid artery walls, 5 mm proximal to the bifurcation. The cIMT diameters were collected from each wall and mean thickness values from both sides. Results: This study included 25 adult thalassemia patients who were diagnosed with transfusion-dependent thalassemia. Most subjects were male, with a median age of 25 years, and had an underweight BMI. Patients with underweight BMI had thicker cIMT, both in mean and maximum diameter (p=0.008 and p=0.011, respectively). Conclusion: Additionally, a transfusion frequency of ≥3 per month had a greater maximum diameter cIMT (p=0.046). A moderate positive correlation was observed between average ferritin levels and maximum intima-media thickness (r=0.402, p=0.046)
New data on the huntsman spiders (Araneae, Sparassidae) of China
No full textSparassidae Bertkau, 1872 is the tenth largest family of Araneae, with 11 genera and 288 species known in China.In the current paper, four newly-recorded species from China are provided: Heteropoda acris Korai & Jäger, 2024, Olios sericeus (Kroneberg, 1875), O. suung Jäger, 2012 and Rhitymna plana Jäger, 2003, of which O. sericeus is re-described, based on specimens collected from Xinjiang Uygur Autonomous Region, China. Additionally, a new Thelcticopis species, T. lini sp. nov., is described
Description of two new species of the genus Pteromalus Swederus (Hymenoptera, Pteromalidae, Pteromalinae) from Xinjiang, China
No full textTwo new species of Pteromalus Swederus (Hymenoptera, Pteromalidae, Pteromalinae), Pteromalus steppensis Li & Hu, sp. nov. and Pteromalus xiaomoheensis Yan & Li, sp. nov., are described and illustrated for the first time. Pteromalus steppensis Li & Hu, sp. nov. was reared as a primary, solitary ectoparasitoid of the larval and pupal stages of Orchestes steppensis Korotyaev, 2016 (Coleoptera, Curculionidae). Figures of its development and its host damage are also provided
Bats of a feather: Range characteristics and wing morphology predict phylogeographic breaks in volant vertebrates
No full textIntraspecific genetic variation and phylogeographic structure can be influenced by factors such as landscape features, environmental gradients, historical biogeography and organismal traits such as dispersal ability. Since deep genetic structure is often considered a precursor to speciation, identifying the factors that are associated with genetic structure can contribute to a greater understanding about diversification. Here, we use repurposed data to perform a global analysis of volant vertebrates (i.e. bats and birds) to estimate where intraspecific phylogeographic breaks occur and to identify the factors that are important predictors of these breaks. We estimate phylogeographic breaks using Monmonier’s maximum difference barrier algorithm and conduct a random forests analysis using the presence of a phylogeographic break as a response variable. In bats, phylogeographic breaks are concentrated in biodiversity hotspots while breaks estimated in bird species are more widespread across temperate and tropical zones. However, for both clades, geographical features such as maximum latitude, measures of wing morphology and organismal traits associated with feeding ecology were found to be important predictors of phylogeographic breaks. Our analysis identifies geographical areas and suites of organismal traits that could serve as a starting point for more detailed studies of biodiversity processes. Highlights Phylogeographic breaks, particularly in species with high dispersal ability, are of interest to evolutionary biologists as a potential precursor to speciation. Repurposed data can be used to identify large-scale trends in biodiversity. Monmonier’s maximum differences algorithm can be employed to estimate phylogeographic breaks using georeferenced sequence data. For volant vertebrates, phylogeographic breaks are predicted by aspects of geographic range, wing morphology and feeding ecology. In bats, breaks are concentrated in tropical biodiversity hotspots while phylogeographic breaks in birds are more evenly distributed across temperate zones
Development and optimization of an innovative raft-forming antiemetic gastro-retentive system
No full textGastro-retentive drug delivery systems are vital for enhancing bioavailability and prolonging gastric residence time, especially for drugs with a short half-life like Ondansetron HCl. This study developed a raft-forming gastroretentive drug delivery system using a polyelectrolyte complex (PEC) of Chitosan and anionic polymers to improve stomach retention, regulate drug release, and enhance therapeutic efficacy. Various formulations were optimized based on polymer type, ratio, cross-linking agent concentration, and hydroxypropyl methylcellulose (HPMC K100M). The best formulation (F12: Chitosan: Carbopol 934) showed high entrapment efficiency (98%), drug loading (11.5%), buoyancy (>12 hours), extended drug release (over 12 hours), and a swelling ratio of 1584% at 8 hours. FTIR and DSC confirmed PEC formation and stability, while FE-SEM demonstrated homogeneity. Drug release followed non-Fickian kinetics, indicating that both diffusion and matrix relaxation contributed to the drug release. This PEC-based system shows promise for sustained stomach delivery of Ondansetron HCl, improving therapeutic efficacy and patient adherence
TDV-optimization: A novel numerical method for phytosociological tabulation
No full textI present the Total Differential Value (TDV), an index designed for vegetation analysis based on the operational concept of differential species, as classically illustrated by Heinz Ellenberg and Dieter Mueller-Dombois. Given a phytosociological table and a grouping of its relevés, TDV is obtained by averaging the Differential Value (DiffVal) for each species in the table. DiffVal, grounded in combinatorial-discrete mathematics, quantifies the differential power of a species. The novelty of this approach lies in its distinction between two types of species absences: (i) absences from some relevés within a group and (ii) absences from all relevés representing a group. By leveraging the distribution of species absences among groups, this method effectively quantifies the differential power and distinguishes differential from non-differential species. I illustrate the computation of DiffVal and TDV and show that, because only differential species contribute to TDV, it reflects the strength of the differential species patterns in a classified table. TDV can be optimized (TDV-optimization), providing partitions of relevés. I demonstrate TDV-optimization using both an artificial and a well-known real-world data set. Key features of this method include its ability to identify patterns very closely resembling manual phytosociological tabulation and to detect reticulate patterns. TDV-optimization may lead to partitions where outlier or extreme relevés are isolated in groups; however, enforcing a minimum group size can highlight partitions with more balanced group sizes. An R package is now available, implementing DiffVal and TDV calculation as well as TDV-optimization. Abbreviations: DiffVal = Differential Value; EllPar = Ellenberg’s partition into three groups; NDR = number of discrepant relevés; NSS = number of significant species; TDV = Total Differential Value
Demography and Culture in Russia: Life History Trade-Offs in Regional Differences
No full textThis study investigates the links between life history strategy (LHS), IQ, and individualism/collectivism (IND/COL) across Russian regions. It is the first to examine regional differences in LHS, illustrating how biological trade-offs are linked to cultural values within a country and separately considering the role of cognitive abilities in this relationship. We hypothesize that cultural differences between regions can be understood through human behavioral ecology, specifically the trade-offs associated with LHS. Data from 83 Russian regions were used to create indices for slow LHS (sLHS) and IND/COL. The sLHS index included indicators like teenage fertility rates, rates of third or higher births, average height, educational attainment, and interest in human sexual behavior (using Google Trends data). The IND/COL index was constructed from indicators like the proportion of multigenerational and single-person households, divorce rates, and search data indicating ingroup identity expression. Regional IQ scores were derived from a large-scale online test administered to over 230.000 individuals across these regions. Our findings reveal strong positive correlations between sLHS, IQ, and IND/COL across Russian regions. Mediation analysis suggests that IQ likely fully mediates the relationship between sLHS and IND/COL. Geographical analysis showed clear patterns of spatial clustering, with gradients linked to latitude and altitude. Additionally, five latent regional profiles emerged from the data, indicating distinct patterns among the regions. These results, while acknowledging certain limitations, underscore the importance of LHS in understanding regional cultural differences. They also point to the need for Russian social policies to adapt to the unique characteristics of each region
Europe’s lost landscape sculptors: Today’s potential range of the extinct elephant Palaeoloxodon antiquus
No full textThe straight-tusked elephant (Palaeoloxodon antiquus) was amongst the largest herbivores once engineering the European landscape on a continental scale. In combination with the glacial-interglacial cycles of the Pleistocene, the species was an integral part of the control regimes that shaped European flora and fauna. With the human-facilitated extinction of the straight-tusked elephant, these landscape-forming processes were lost during the last Glacial-Interglacial cycle. Given today’s climate, could straight-tusked elephants still be part of modern ecosystems in Europe? And if yes, where? Answers to these questions can support nature conservation in preserving species and ecosystems historically adapted to these lost control regimes. We reconstructed the realised niche of the straight-tusked elephant by allocating a novel compilation of fossil occurrences to either cold or warm stages, based on their assignment to Marine Isotope Stages. Further, we quantified the past potential distribution of the straight-tusked elephant since its extinction and its current potential distribution given the modern climate. Results show that the elephant could have persisted in the Mediterranean Basin until today and that modern climate across Central and Western Europe, excluding the Alps, as well as in the Mediterranean, is highly suitable for its occurrence. Our results show that, without human-induced extinctions, European fauna would comprise extinct megafauna, acting as ecosystem engineers on a continental scale. Local rewilding initiatives aim at restoring these lost processes, but potentially cannot achieve lasting ecological effects on comparable scales. Highlights The current European climate would still be suitable for the extinct straight-tusked elephant (Palaeoloxodon antiquus). The straight-tusked elephant could have persisted during the last Glacial-Interglacial cycle, considering past climate. Conserving the ecosystems shaped by the top-down ecosystem functions executed by the straight-tusked elephant in Europe may be especially promising in regions where the elephant could still exist today. Using reference cold and warm stages, based on Marine Isotope Stages in a Species Distribution Modelling framework, is a promising attempt to overcome dating uncertainties inhibiting more specific niche reconstructions of extinct species