In behavioral genetics, divorce is typically analyzed as an individual-level outcome, even though marital dissolution can only be experienced by couples. In this article, we discuss how assortative mating complicates the study of couple-shared outcomes because individual-level effects can be confounded by effects of the spouse. We then show how chain-linking affines (i.e., in-laws) provides sufficient information to estimate spousal similarity for couple-shared outcomes, which we incorporate into an extended twin model that we use to test for sex differences and assortative mating for individuals’ liability to divorce. We linked the Norwegian twin register to the Norwegian population register and constructed 124,544 extended family units (1196 units with monozygotic twins) comprising 353,210 marriages entered between 1983 and 2008. We found that divorce was significantly correlated among affines, and that female relatives were more highly correlated than male relatives. The extended twin model estimated a strong correlation (r = .60, SE = .10) between female and male familial factors. Couples’ liability to divorce was attributed to 18% (SE = 5%) female and 10% (SE = 3%) male familial factors, with an additional 16% (SE = 4%) accounted for by their correlation. Estimates from a classic twin model were considerably higher. These findings show that spousal similarity is an important source of variation in divorce liability and that failing to model it can inflate estimates of individual-level effects. Overall, the analytical framework offers a blueprint for dissecting any couple-shared outcome into sex-specific and assortative components.

Psalidodon bifasciatus is a small characiform, originally described as endemic to the Iguaçu River basin. However, a recent study recorded a population of P. bifasciatus in the Piquiri River basin (upper Paraná), although data on its geographic distribution and parasitological aspects are still limited. The study characterized the parasitic fauna of P. bifasciatus in two streams, one from each basin, and compared them in terms of richness, diversity, and parasite community structure. Twenty-six females were collected in a stream in the lower Iguaçu River basin, and 25 females in a stream in the Piquiri River basin (upper Paraná) in September 2018. The parasite community structure of P. bifasciatus differed between areas, with a predominance of monopisthocotyls and greater richness of parasitic taxa for hosts in the lower Iguaçu River basin. In the Piquiri River basin (upper Paraná), the parasite community was characterized by a higher prevalence of larval nematodes and a lower richness of parasite taxa. The differences in the richness and structure of the parasite communities between the two areas support the hypothesis of the introduction of P. bifasciatus into the Piquiri River basin (upper Paraná). Therefore, we emphasize the need for further studies addressing the distribution pattern of P. bifasciatus, as well as additional parasitological studies to determine whether the parasitological taxa of P. bifasciatus are shared in other hydrological systems. This study contributes to the knowledge of the biological aspects of P. bifasciatus in both basins and improves our understanding of how host-parasite interactions can be informative in species introduction scenarios.

Individual social identities indicate group affiliations and are typically associated with group-typical preferences, signals that indicate group membership, and the propensity to condition actions on the social signals of others, resulting in group-differentiated interaction norms. Past work modeling identity signaling and coordination has typically assumed that individuals belong to one of a discrete set of groups. Yet individuals can simultaneously belong to multiple groups, which may be nested within larger groupings. Here, we introduce the generalized Bach or Stravinsky game, a coordination game with ordered preferences, which allows us to construct a model that captures the overlapping and hierarchical nature of social identity. Our model unifies several prior results into a single framework, including results related to coordination, minority disadvantage, and cross-cultural competence. Our model also allows agents to express complex social identities through multidimensional signaling, which we use to explore a variety of complex group structures. Our consideration of intersectional identities exposes flaws in naive measures of group structure, illustrating how empirical studies may overlook some social identities if they do not consider the behaviors that those identities function to afford.

The diverse cutthroat eel family Synaphobranchidae comprises 13 genera and 57 species of mostly deep-sea fishes documented from all oceans. Here, we report on the catch of a single synaphobranchid specimen in the Kong Haakon VII Sea off Dronning Maud Land, representing the first record of the genus Ilyophis in the Southern Ocean. The specimen was trawled at a depth of 1500 m during the 2019 joint expedition of the Norwegian Polar Institute, Institute of Marine Research (Norway), the University of Bergen (Norway), the Arctic University of Norway, the University of Science and Technology (Norway) and the Stellenbosch University (South Africa) onboard the Norwegian research vessel Kronprins Haakon. The specimen is deposited in the ichthyological collection of the University Museum Bergen. In this study, we tentatively identify the specimen as Ilyophis cf. maclainei based on an integrative taxonomic approach. Phylogenetic analysis of mitochondrial partial cytochrome oxidase I places the Antarctic specimen in a clade of sequences deposited in Barcode of Life Data System (BOLD) as Ilyophis sp., Ilyophis cf. brunneus and Ilyophis brunneus. Morphological data show overlaps in some morphometric and meristic characters with I. brunneus and the recently described I. maclainei - with no genetic samples currently being available for the latter. Our analysis reveals taxonomic issues within I. brunneus and the need for increased sampling and a worldwide taxonomic revision of I. brunneus. The full mitochondrial DNA of the Antarctic specimen is reconstructed as a resource for future research.

Conservation of the Pemba flying fox Pteropus voeltzkowi, endemic to Pemba, Zanzibar, has been a success story. Low numbers last century prompted a local conservation response that likely resulted in a 400% increase in the population. But, with project funding having been gradually reduced over 15 years, it is unclear whether the population has maintained its recovery. Here we report findings from a new survey, in 2024, showing that the population size is that of the recovered population in 2008. However, many P. voeltzkowi have moved to urban centres, probably to avoid disturbance, primarily hunting by children. Only half the people interviewed remembered the earlier conservation campaign, but nearly all would support an environmental education campaign aimed at children in schools.

Climate change is projected to alter the biology and distribution of many helminth species. We investigated the influence of climate on the current distribution of Parapharyngodon sceleratus, a monoxenic, generalist nematode parasite infecting 29 lizard species in South America, and evaluated its potential future range shifts under climate change. Using ecological niche modelling, we predicted the species’ current and future range distributions. Precipitation-related variables were the primary determinants of the spatial distribution of the worm. Areas of medium to high environmental suitability are concentrated in regions with seasonal tropical warm climates, as well as temperate regions with dry summers and mild winters. Future projections indicate a progressive reduction of highly suitable areas and an expansion of areas with low suitability, particularly in northern and central South America, by 2100. However, the Atlantic Forest, the northeastern Brazilian coast, a site within the semiarid Caatinga, and open vegetation areas in Chile persist as refugia of high habitat suitability. Our findings suggest that rising temperatures and altered precipitation patterns may constrict the geographic range of this helminth. Contrary to predictions for other parasite taxa, our results highlight a negative impact of climate change on the distribution of a monoxenic helminth.

Variation in orchid seed size and shape can be linked to phylogenetic relationships, habitat preferences, germination behaviour or dispersal strategies. To investigate this, we compared 45 orchid species from 29 genera collected across different localities in Cameroon using optical microscopy. We categorized each species according to lifeform (38 epiphytic vs. 7 terrestrial), altitudinal range (11 mountain vs. 34 lowland) and geographic distribution (28 widespread vs. 17 range-restricted). We analysed seed morphology using phylogenetic signal tests, analysis of variance and principal component analysis. Our results confirm a clear distinction between epiphytic and terrestrial species, with intermediate morphologies observed in genera encompassing species with both lifeforms (Cynorkis, Graphorkis, Habenaria and Liparis). Certain traits, such as seed length and seed air space, show a strong phylogenetic signal, suggesting that these traits are more linked to ancient evolutionary history than to recent ecological adaptation. Among the 38 epiphytic species, no consistent relations were found between seed traits and either geographic range or altitudinal distribution. Our findings suggest that the variation observed in seed morphology among African orchids is influenced more by phylogenetic relationships than by present-day distribution.

Interaction with humans in early life is known to influence animal behaviour, stress responses, and welfare, but whether animals perceive gentle handling as emotionally positive remains unclear. Here, we used a conditioned place preference paradigm widely used in affective neuroscience but rarely implemented in poultry, to assess whether chicks experience positive emotions when gently handled. Twenty Hy-Line W-80 chicks were tested in a two-chamber apparatus distinguished by colour cues. Following baseline preference assessment, chicks were exposed to conditioning sessions in which chambers were paired with either gentle handling treatment (soft stroking and calm talking) or a neutral human presence (static and silent). Chicks received six 5-min sessions of each treatment across 12 days, on alternating days (one session per day), and colour-treatment pairings were counterbalanced across individuals. Post-conditioning preference was assessed over three consecutive days. Chicks consistently spent more time in the chamber previously associated with gentle handling across test days. Importantly, chicks did not show an aversion to the neutral chamber. These results indicate that gentle human contact acquired positive associative value rather than merely reducing aversion. These findings provide experimental evidence that human-animal interactions can function as rewarding stimuli in poultry, which has implications for husbandry practices and welfare assessment frameworks.

Lizards represent a diverse group, adapted to a wide variety of environments, and interact with a wide range of parasites. The composition of a parasitic community can be influenced by several factors, including the host, the environment, and the parasite itself. This study evaluated the composition of the helminth community in three species of lizards of the genera Ameiva, Ameivula, and Tropidurus, from a Carrasco habitat in Chapada do Araripe, Brazil. Carrasco is a little-explored environment in which the diversity of hosts and parasites is still poorly understood. The composition of the helminth community associated with lizard species was evaluated by comparing richness, evenness, dominance, and diversity among component communities, including host sex and size as influencing factors, using different statistical comparison tools. The community consisted of 12 taxa from eight genera of parasitic helminths, seven of which were Nematoda and one Cestoda. The factors analysed had different influences on the different parasitic communities of each host species. It was possible to determine the dissimilarity between host populations based on their parasitic communities, and it was observed that the host species itself represented the most important factor in the structuring of helminth communities. The information recorded here converges with other results obtained in different studies with lizards, but points to patterns in the helminth community that differ from those observed in other areas of the Caatinga. The results obtained reveal complex patterns of association between parasites and hosts, demonstrating the existence of ecological relationships that can be shaped by specific factors.

A series of laboratory experiments was conducted to evaluate the germination ecology of buttongrass [Dactyloctenium radulans (R. Br.) P. Beauv.] for designing weed management practices in eastern Australia. Two populations (BG3 and BG4) were evaluated under varying temperature, light, salinity, water stress, residue cover, and burial depth conditions. Germination was completely inhibited at 15/5 C (alternating day/night temperature regime) but increased at high temperature regimes, reaching 90–92% at 30/20 C and remaining high (72–88%) at 35/25 C, indicating strong adaptation to warm climates. Both populations germinated well in light (12 h)/dark (12 h) conditions (87–93%), while BG3 showed a reduction (80%) in complete darkness (24 h) compared with light/dark conditions, suggesting weak positive photoblastic behaviour. Germination decreased progressively with increasing sodium chloride (NaCl) concentrations, with 50% inhibition at 40 mM NaCl, indicating moderate salt tolerance. Germination was reduced by 50% at osmotic potentials of -0.30 MPa and -0.25 MPa for BG3 and BG4 populations, respectively. Seedling emergence declined with increasing sorghum residue loads, dropping by >80% at >6 Mg ha-1, and was completely inhibited at 8 cm burial depth. These results demonstrate that D. radulans is a thermophilic, light-responsive, shallow-emerging grass capable of germinating under moderate salinity and water stress conditions, enabling persistence in semi-arid and reduced-tillage systems. High residue retention and deep burial of seeds (≥8 cm) could significantly suppress emergence, providing ecologically sustainable management options. Future studies should quantify population-level physiological variations and integrate temperature, moisture, and residue interactions into predictive emergence models to guide region-specific weed management under changing climatic conditions.

This study aimed to evaluate adherence to the Mediterranean diet, a recognised healthy eating pattern, and the tendency towards orthorexia nervosa in professional athletes, and to examine their relationship with physical activity levels. The study was conducted with athletes (n 134) at the Turkish Olympic Preparation Center (TOHM). Data were collected using a questionnaire covering sociodemographic information, dietary habits, anthropometric measurements, the Mediterranean Diet Quality Index (KIDMED), the International Physical Activity Questionnaire-Short Form (IPAQ-SF) and the Orthorexia-11 (ORTO-11) scale assessing orthorexic tendencies. Of the participants, 17·2 % had poor dietary quality, 60·4 % moderate and 22·4 % good dietary quality. According to the ORTO-11 (cut-off ≤ 25 points), 30·6 % of athletes exhibited orthorexic tendencies. Athletes adhering to a diet had significantly higher orthorexia tendencies compared with non-dieters (P < 0·05). A significant association was found between athletic experience and orthorexic tendencies, particularly among those with 4–8 years and ≥8 years of experience (P < 0·05). Moreover, athletes consuming three main meals had significantly higher KIDMED and ORTO-11 scores than those consuming two meals (P < 0·05). No statistically significant correlation was found between the KIDMED score, ORTO-11 score and physical activity level (P > 0·05). Professional athletes showed moderate adherence to the Mediterranean diet, while certain groups displayed higher orthorexia tendencies. Diet quality and orthorexic tendencies differed significantly with eating habits such as athletic experience and meal patterns, whereas physical activity level had no effect. These findings highlight the importance of multidisciplinary nutrition strategies focusing on both performance and sustainable healthy eating behaviours.

In a review article published in this journal in 2010, we described the mitigation and adaptation potential of organic agricultural systems. In this article, we reflect on our findings and update the results from 2010. Today’s scientific evidence confirms that the principles of organic agriculture can facilitate a transition to climate-neutral food systems. Compliance with only mandatory requirements of organic certification is not sufficient for climate neutrality but can significantly offsets agricultural emissions by avoiding mineral fertilizers and increasing soil carbon sequestration. Most relevant to achieve climate neutrality of the food system is a shift toward more plant-based diets. Although behavioral change is more challenging to achieve, the principles of organic agriculture can positively trigger a climate-sensitive mind-shift of consumption and production patterns. Organic farming methods can also significantly contribute to climate adaptation in terms of better resilience under climatic variability and stress conditions. The all-encompassing systemic approach of organic agriculture indicates a viable path to food system resilience to climate change.

The lowland tapir Tapirus terrestris is confined to South America and is categorized as Vulnerable on the IUCN Red List. The species was extinct in the state of Rio de Janeiro in Brazil by the early 20th century but during 2017–2021, 14 individuals from six captive groups were reintroduced through a soft release method in the Guapiaçu Ecological Reserve in the Atlantic Forest. The reintroduced population was continually monitored with camera traps during the pre-release acclimatization period and after release. The released tapirs decreased the proportion of diurnal activity but did not decrease daily activity levels. Their activity patterns differed between the acclimatization period and post-release, as well as between the dry and wet seasons, but there was no difference between the activity of males and females. The tapirs modified their activity patterns over the course of the reintroduction period, showing an increasing resemblance to the behaviour of wild populations.

Native boxwood across Europe has been destroyed by the invasive moth Cydalima perspectalis. To date, climatic conditions and natural enemies have not been able to contain the pests. Increases in temperature due to climate change (CC) may affect insect development and voltinism, with species-specific effects. Its spread across European countries indicates that the expansion of C. perspectalis is not limited by cold winters. However, in southern Europe, rising maximum temperatures can affect pests and their host plants. Despite this, the effects of high temperatures on herbivorous pests have been studied far less extensively than those of low temperatures. Our results show that elevated temperatures accelerate egg development but prolong larval development, reduce adult longevity and fertility, and substantially increase mortality across the egg, larval, and pupal stages. These findings indicate that spring–summer temperatures in the Mediterranean Basin are approaching the upper thermal limits of this species and that further warming is unlikely to facilitate its expansion in this region. Although high temperatures did not reduce diapause induction, they increased larval mortality, and field monitoring showed that altitude, more than thermal time, dominated the patterns of first-flight emergence. Habitat orientation (North or South) may further mediate pest–host coexistence. Overall, this study contributes to the literature by clarifying how this pest responds to the warming conditions associated with CC in southern Europe.

Persons with mental illnesses may experience stigma from their immediate family members in addition to other forms of stigma. The researchers used semi-structured interviews to investigate the experiences of familial mental illness stigma among 15 people diagnosed with mental illnesses in a mid-sized city in Canada. Five themes that spoke to participants’ experiences of familial mental illness stigma and ways to reduce it were identified by the investigators. The themes included: diagnosis as a ‘double-edged sword,’ potential familial isolation, familial stigma as societal stigma localized, stories of acceptance and support, and confronting potential familial mental illness stigma. Participants’ narratives indicate that familial mental illness stigma is rooted in the broader social or public stigma, which sees its way into familial relations as well. This stigma takes various forms, including relationship bias or unfair treatment, breakdown in romantic relationships, loss of status, verbal and emotional abuse, exclusion from decision-making, and alienation within their immediate and extended families. Familial mental illness stigma experiences negatively impact participant’s psychological well-being and personal empowerment. However, participants also shared ways that family members create supportive environments or actively confront or prevent stigma. Overall, this study has contributed to knowledge on mental illness stigma, particularly familial mental illness stigma from the perspective of participants living with a mental illness in a high-income country. Suggestions for future research include a focus on strategies to prevent ongoing familial mental illness stigma, and large-scale studies to explore familial mental illness stigma to understand why families might themselves at times perpetrate stigma.

Self-rated health (SRH) is a validated epidemiological measure that captures an individual’s overall health perception and predicts morbidity and mortality. Despite extensive research on SRH among older adults in India, evidence on its transition across the life course remains limited. Using data from 70,595 individuals aged 45 years and above from the Longitudinal Aging Study in India (LASI) 2017–2018, this study examined transitions in SRH from childhood to older adulthood. An adverse SRH trajectory was defined as a shift from good childhood health to poor or fair health in later life. Descriptive, bivariate, and multivariable logistic regression analyses were conducted. Overall, 51% of older adults experienced an adverse SRH trajectory. Higher odds were observed among women (AOR: 1.30), individuals with substance consumption (AOR:1.24), chronic multimorbidity (AOR: 3.37), functional limitations (AOR: 2.03), and depression (AOR: 1.51). Early-life disadvantages – child labour, child marriage, and persistent household poverty – were also significant risk factors. In contrast, higher education and participation in social and physical activities were protective. These findings indicate that an adverse subjective health trajectory is shaped by cumulative life-course exposures rather than ageing alone. Strengthening early-life social investments and community-based wellness initiatives is vital to promote healthy and equitable ageing in India.

The dendrophylliid ‘sun corals’ are a group of highly dispersive scleractinians that became invasive in the Atlantic Ocean. A recent study, focusing on the corallite macro- and micromorphologies, remarkably expanded the number of Tubastraea species in the Southwestern Atlantic, including the description of four new corals to the world: Tubastraea grandidentata, T. megalostoma, T. columnata, and T. ramosa, which are validated in the present study. The increasing biodiversity of sun corals demands the application of alternative tools, such as molecular markers, to corroborate findings at the morphological level. Hence, a DNA analysis based on COI, IGR, and ITS1-5.8S-ITS2 rDNA regions is used to infer the phylogeny of the new species described from Brazil. The rDNA is the most variable region and dramatically impacts the phylogenetic reconstruction, supporting the species identity of the ‘Brazilian’ Tubastraea and indicating two major clades: branched and unbranched corals. The most robust phylogeny is obtained by concatenating the three genetic regions using Bayesian inference. Genetic polymorphisms and fixed differences are observed within and between species. Data also support the identity of Atlantia caboverdiana from the Northeastern Atlantic. Finally, the unprecedented biodiversity of sun coral species in the Tropical Atlantic raises concerns about all previous identifications and the mechanisms involved in the dispersion of Tubastraea across the world. Moreover, multiple introductions, gene flow, and larval competency period remain misunderstood, challenging the management policies hitherto adopted to control these exotic dendrophylliids.