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The major histocompatibility complex (MHC) plays a critical role in the immune response against pathogens. Its high polymorphism is thought to be mainly the consequence of host‐pathogen co‐evolution, but elucidating the mechanism(s) driving MHC evolution remains challenging for natural populations. We investigated the diversity of MHC class II genes in a wild population of pied flycatchers Ficedula hypoleuca and tested its associations with two key components of individual fitness: lifetime reproductive success and survival. Among 180 breeding adults in our study population, we found 182 unique MHC class II exon 2 alleles. The alleles showed a strong signal of positive selection and grouped into nine functional supertypes based on physicochemical properties at the inferred antigen‐binding sites. Three supertypes were found in > 98% of the sampled individuals, indicating that they are nearly fixed in the population. We found no rare supertypes in the population, as all supertypes were present in > 70% of individuals. Three supertypes were related to different components of individual fitness: two were associated with lower offspring production over time, while the third was positively associated with survival. Overall, the substantial allelic and functional diversity and the relationship between specific supertypes and fitness are in accordance with the notion that balancing selection maintains MHC class II diversity in the study population, possibly with fluctuating selection as the underlying mechanism. The absence of rare supertypes in the population suggests that the balancing selection is not driven by rare‐allele advantage. [ABSTRACT FROM AUTHOR]

Rich materials can provide more opportunities for exploring the mechanisms of speciation driven by sexual selection. Being the fastest‐evolving arthropods to date, the sword‐tailed crickets of Nudilla Gorochov, 1988 (= Laupala Otte, 1994) have rapidly diverged primarily due to the variability of their calling songs (sexual signals). In addition, they also exhibit morphological conservatism, with little variation between species. Similar circumstances can be seen in tree crickets (Oecanthinae), which have conservative morphology and a diverse range of song variations. Thus, we believe that tree crickets could serve as a model for research on sexual selection since they share a similar evolutionary history and mode of differentiation with Nudilla. However, due to the improper methods in analyzing the calling songs and nearly identical morphological features between taxa, there are many problems with the taxonomy of Oecanthinae in China. To solve these problems, we conducted an integrative taxonomic study of Chinese Oecanthinae based on comparative morphology, species delimitation, acoustical analysis, and phylogenetic analysis. This study recognized 12 Oecanthinae species in China, including four new species, and confirmed one new synonym and two misidentifications. Meanwhile, we confirmed the morphological stability of Oecanthinae, and revealed that variation in color, size, and morphology may be intraspecific polymorphism, which sometimes does not reflect the species relationships. The result indicates that the acoustic parameter freq.median can be used for efficient and accurate species delimitation in Oecanthinae. We speculate that incomplete species divergence leads to complexity in species relationships at the genetic level of Oecanthinae. The conservation of morphological characters, the interspecificity of songs and the complexity of species relationships suggest that sexual selection have played a role in the evolution of Oecanthinae. Our study resolves some systematic and taxonomic problems of Oecanthinae, clarifies the species relationships of Oecanthinae in China, and provides clues for expanding the cricket groups to be used in speciation studies. [ABSTRACT FROM AUTHOR]

Stripes and bands are common colour patterns in snakes. Some species are known to exhibit colour polymorphism and that includes expressing it in the bands and stripes. Bridal snake, Dryocalamus is a medium‐sized arboreal snake in South to Southeast Asia and most species of the genus are banded, but including two striped species. In Borneo, banded D. subannulatus and striped D. tristrigatus occur sympatrically and the two species are similar morphologically except for their colour patterns. We hypothesized the two species in Borneo exhibit a significant colour dimorphism of one species and conducted morphological and genetical analysis to test the hypothesis. Morphological examinations revealed that D. subannulatus and D. tristrigatus are not distinguishable in Borneo by scalation. Mitochondrial phylogenetic analysis and nuclear SNP analysis showed D. subannulatus and D. tristrigatus from Borneo formed clades or clusters by region not by species. Dryocalamus subannulatus and D. tristrigatus in Borneo are morphologically and genetically indistinguishable and Bornean D. subannulatus should be treated as a colour morph of D. tristrigatus. This is a rare example of sympatrically distinct banded/striped dimorphism in snakes. Relative abundance of banded/striped morph of the genus is probably different depending on region, and any ecological factor may contribute to it. [ABSTRACT FROM AUTHOR]

ABSTRACT Introduction Methods Results Conclusions The link between DNA repair gene polymorphisms and cancer susceptibility has gained significant attention. Thus, we investigated the impact of base excision repair (BER) gene polymorphisms on acute myeloid leukemia (AML) risk and pathogenesis.In total, 106 patients with AML and 191 healthy controls were included in the study, wherein polymorphisms in four BER genes (APEX1, MUTYH, OGG1, and XRCC1) were examined.Notably, the APEX1‐656 T>G polymorphism exhibited a significant association with AML risk in the recessive (TT vs. TG + GG) (p = 0.046) and co‐dominant models (TT vs. GG) (p = 0.02). Assessing APEX1 expression levels, APEX1 expression was elevated in the bone marrow of patients with AML compared with that in controls (p = 0.02). Subsequently, we compared the percentages of CD34+ cells between the APEX1 high or low expression groups, revealing a significant difference (high vs. low = 29.9% vs. 11.5%, p = 0.01). Additionally, we observed reduced APEX1 expression in HL60 cells differentiated with all‐trans retinoic acid (p < 0.001). We hypothesized that APEX1 expression could correlate with stemness and analyzed its expression in stem and differentiated cells.In the GSE48558 dataset, AML cells and normal CD34+ cells expressed APEX1 at higher levels than did granulocytes (p < 0.01). Functional experiments revealed that APEX1 knockdown led to a reduction in AML cell proliferation. These findings indicated that APEX1 polymorphisms were a potential risk factor for AML and highlighted the important role of APEX1 in regulating AML cell differentiation and proliferation. [ABSTRACT FROM AUTHOR]

ABSTRACT Organelle genomes serve as crucial datasets for investigating the genetics and evolution of plants and animals, genome diversity, and species identification. To enhance the collection, analysis, and visualisation of such data, we have developed a novel open‐source software tool named Organelle Genome Utilities (OGU). The software encompasses three modules designed to streamline the handling of organelle genome data. The data collection module is dedicated to retrieving, validating and organising sequence information. The evaluation module assesses sequence variance using a range of methods, including novel metrics termed stem and terminal phylogenetic diversity. The primer module designs universal primers for downstream applications. Finally, a visualisation pipeline has been developed to present comprehensive insights into organelle genomes across different lineages rather than focusing solely on individual species. The performance, compatibility and stability of OGU have been rigorously evaluated through benchmarking with four datasets, including one million mixed GenBank records, plastid genomic data from the Lamiaceae family, mitochondrial data from rodents, and 308 plastid genomes sourced from various angiosperm families. Based on software capabilities, we identified 30 plastid intergenic spacers. These spacers exhibit a moderate evolutionary rate and offer practical utility comparable to coding regions, highlighting the potential applications of intergenic spacers in organelle genomes. We anticipate that OGU will substantially enhance the efficient utilisation of organelle genomic data and broaden the prospects for related research endeavours. [ABSTRACT FROM AUTHOR]

ABSTRACT This study aims to investigate the association of rs11203366, rs11203367, rs874881, rs2240340 and rs1748033 polymorphisms of protein‐arginine deiminase type 4 (PADI4) gene with the risk of rheumatoid arthritis (RA) through a meta‐analysis that was followed with a bioinformatics approach. The data were collected from reputable articles and underwent quantitative analysis, followed by in silico analysis using some bioinformatics tools. The results showed that rs874881 polymorphism in Latino (G vs. C: OR = 1.35, 95% CI = 1.11–1.65, p = 0.003; GG + CG vs. CC: OR = 2.02, 95% CI = 1.41–2.89, p = 0.0001; CG vs. CC + GG: OR = 1.38, 95% CI = 1.04–1.83, p = 0.027; GG vs. CC: OR = 2.09, 95% CI = 1.35–3.23, p = 0.001; CG vs. CC: OR = 1.98, 95% CI = 1.36–2.87, p = 0.00033) and rs1748033 in Caucasian population (T vs. C: OR = 1.25, 95% CI = 1.07–1.45, p = 0.005; TT vs. CT + CC: OR = 1.34, 95% CI = 1.09–1.64, p = 0.005, TT + CT vs. CC: OR = 1.26, 95% CI = 1.09–1.44, p = 0.001; TT vs. CC: OR = 1.59, 95% CI = 1.13–2.23, p = 0.007; CT vs. CC: OR = 1.20, 95% CI: 1.04–1.39, p = 0.015) are associated with increased risk of RA. Moreover, rs11203366 (G vs. A: OR = 1.46, 95% CI = 1.19–1.78, p = 0.0002, GG vs. AG + AA: OR = 1.42, 95% CI = 1.01–2.01, p = 0.043; GG + AG vs. AA: OR = 2.03, 95% CI = 1.45–2.86, p = 0.00004; GG vs. AA: OR = 2.29, 95% CI = 1.49–3.51, p = 0.0002; AG vs. AA: OR = 1.93, 95% CI = 1.35–2.76, p = 0.0003) and rs11203367 (T vs. C: OR = 1.50, 95% CI = 1.23–1.83, p = 0.00007; TT vs. CT + CC: OR = 1.56, 95% CI = 1.12–2.18, p = 0.009; TT + CT vs. CC: OR = 2.02, 95% CI = 1.43–2.84, p = 0.00007, TT vs. CC: OR = 2.43, 95% CI = 1.59–3.71, p = 0.0004; CT vs. CC: OR = 1.86, 95% CI = 1.30–2.68, p = 0.0007) had an impact in the Latino population. Bioinformatics tools showed the effect of these polymorphisms on gene function. These findings suggest that rs11203366, rs11203367, rs874881 and rs1748033 polymorphisms may be genetic risk factors for RA. Moreover, differences between populations suggest that ethnicity may play an important role in the effect of these polymorphisms on RA risk. [ABSTRACT FROM AUTHOR]

ABSTRACT This study sought to investigate the association between interleukin‐10 (IL10) polymorphisms and susceptibility to Sjögren's syndrome. A systematic search of the Medline, Embase and Web of Science databases was conducted to identify relevant articles from inception to April 2024. No restrictions were placed on race, ethnicity or geographic area, but only studies published in English were included. A meta‐analysis was conducted to evaluate the association among the IL10‐1082 G/A (rs1800896), ‐819 C/T (rs1800871) and ‐592 C/A (rs1800872) polymorphisms, as well as their haplotypes and the risk of developing Sjögren's syndrome. The included studies involved 998 Sjögren's syndrome patients and 1576 controls. Ten studies were included in the meta‐analysis. Meta‐analysis of the IL10‐1082 G/A polymorphism revealed no significant association with Sjögren's syndrome (odds ratio [OR] = 1.115, 95% confidence interval [CI]: 0.888–1.401, p = 0.343), with stratification by ethnicity yielding consistent results for Europeans and Latin Americans. Similarly, the IL10‐819 C/T polymorphism was not associated with Sjögren's syndrome in any study subjects (OR = 0.859, 95% CI: 0.648–1.138, p = 0.290). The IL10‐592 C allele also exhibited no association with Sjögren's syndrome (OR = 1.131, 95% CI: 0.776–1.646, p = 0.522). However, the GCC carrier status demonstrated a significant association with Sjögren's syndrome across all study subjects (OR = 1.496, 95% CI: 1.200–1.865, p < 0.001), particularly in Europeans (OR = 1.444, 95% CI: 1.085–1.921, p = 0.012) and Latin Americans (OR = 1.324, 95% CI: 1.115–2.366, p = 0.012). A significant protective effect of the homozygous ATA/ATA haplotype on Sjögren's syndrome was found in Europeans (OR = 0.320, 95% CI: 0.121–0.846, p = 0.022).This meta‐analysis indicates a significant link between carrying the GCC haplotype of the IL10‐1082 G/A, ‐819 C/T and ‐592 C/A polymorphisms and an increased susceptibility to Sjögren's syndrome. Conversely, the homozygous ATA/ATA haplotype appears to confer protection against the risk of Sjögren's syndrome, particularly in European populations. [ABSTRACT FROM AUTHOR]

Stinging nettle, Urtica dioica L., is a widely distributed subdioecious long‐rhizomatous plant. Within a single population growing in the territory of the Zvenigorod Biological Station of Lomonosov Moscow State University, eight plots were selected in stinging nettle thickets to study the variability of the sexual reproductive part in U. dioica depending on internal and external factors. As monoecious ramets are relatively common in the studied population, four gender forms were distinguished based on the ratio of male and female flowers. On 156 ramets of different gender forms and 36 genets, it was shown that predominantly male plants are shorter, while predominantly female plants have larger and more widely spread inflorescences compared to other gender forms. The pubescence type (spreading or appressed unicellular hairs) shows the greatest repeatability within the merigenet. True monoecy in stinging nettle is widespread: male and female flowers of different gender forms were found in 10 out of 36 genets. The most common inflorescence architecture types in the studied population were proxigynous and basigynous. Both normal pistillate and normal staminate flowers, as well as flowers with morphological abnormalities formed based on flowers of different sexes can be found on the same ramet, which suggests the presence of paradioecious lability. [ABSTRACT FROM AUTHOR]

Understanding the maintenance of genetic variation in reproductive strategies and polymorphisms in the wild requires a comprehensive examination of the complex interactions between genetic basis, behaviour and environmental factors.We tested the association between three colour genotypes and variation in female pheromone signalling and male antennal morphology in the wood tiger moth (Arctia plantaginis). These moths have genetically determined white (WW, Wy) and yellow (yy) hindwings that are linked to mating success and fitness, with heterozygotes (Wy) having an advantage. We hypothesized that attractiveness and reproductive success are correlated, with Wy females being more attractive than the other two genotypes which could contribute to maintaining the polymorphism.Female attractiveness was tested by baiting traps with females of the three colour genotypes both in low‐ (i.e. field set‐up) and in high‐population density (i.e. large enclosure set‐up). Male's ability to reach females was correlated to their own colour genotype and antennal morphology (length, area and lamellae count).Contrary to our prediction, morph‐related reproductive success and attractiveness were not correlated. Heavier Wy females attracted a lower proportion of males compared to WW and yy females. Specifically, an increase in weight corresponded to a decreased Wy but increased yy female attractiveness. yy females were generally more attractive than others likely due to earlier pheromone release. In males, lamellae count and genetic colour morph were linked to the male's ability to locate females. Furthermore, male traits affected their ability to reach females in a context‐specific way. Males with denser antennae (i.e. higher lamellae count) and white males reached the females faster than yellows in the enclosure, while yellow males located females faster than whites in the field.Our results indicate that higher yy female attractiveness was likely affected by the combined effect of early pheromone release, female weight and higher population density. Males' searching success was affected by morph‐specific behavioural strategies and local population density. Ultimately, the combined effect of genotype‐related pheromone signalling strategies of females together with environment‐dependent male behaviour affect male response and potentially contribute to maintaining variation in fitness‐related traits. [ABSTRACT FROM AUTHOR]

The article explores the seasonal piscivory behavior of pumpkinseed sunfish in pond ecosystems in Southern Ontario, Canada. The study reveals that pumpkinseed sunfish exhibit extensive seasonal fish consumption in ponds, even in the absence of large predators. The findings suggest that mesopredator fish like pumpkinseed may fill the top predator niche in pond ecosystems, highlighting the importance of considering ponds in ecological research and understanding the impacts of expanding mesopredator species on aquatic food webs. The study emphasizes the need for further research to test the mesopredator release hypothesis and quantify the consequences of meso- and top predator expansion in pond ecosystems. [Extracted from the article]

Parasite‐mediated selection is widely believed to play a crucial role in maintaining the diversity of the major histocompatibility complex (MHC) genes, which is thought to be maintained through heterozygote advantage, rare‐allele advantage, and fluctuating selection. However, the relationship between parasite pressure and MHC diversity has yielded inconsistent findings. These inconsistencies may arise from the influence of environmental factors and individual variations in traits on host–parasite interactions. To address these issues, our study extensively investigated populations of striped hamsters inhabiting regions characterized by environmental heterogeneity. The primary objective was to examine the universality of parasite‐mediated selection mechanisms. Our observations revealed the presence of multiple parasite infections, accompanied by spatial and temporal variations in parasite communities and infection patterns among individual hamsters. Specifically, the temperature was found to influence all four parasite indices, while the presence of gamasid mites and parasite richness decreased with increasing precipitation. We also noted significant seasonal variation in parasite dynamics. Moreover, a significant sexual dimorphism was observed with males exhibiting a considerably higher parasite burden compared to their female counterparts. Lastly, we identified the maintenance of MHC polymorphism in striped hamsters as being driven by the heterozygote advantage and fluctuating selection mechanisms. This study underscores the significance of ecological processes in comprehending host–parasite systems and highlights the necessity of considering environmental factors and individual traits when elucidating the mechanisms underlying MHC diversity mediated by parasites. [ABSTRACT FROM AUTHOR]

Several investigations have been carried out to explore the genetic association of TLR4 codon variants, specifically Asp299Gly and Thr399Ile, and susceptibility to sepsis, but the results have been contradictory. The present study aimed to conduct a meta‐analysis to draw a definitive conclusion regarding the role of TLR4 genetic variants (Asp299Gly and Thr399Ile) in sepsis. A thorough literature search was conducted using the PubMed, Scopus, and Science Direct databases. The inclusion and exclusion criteria were established to ensure the accuracy of the data. The Comprehensive Meta‐Analysis Software v4 was utilized to perform the meta‐analysis and related analyses. A total of 13 studies were analyzed, including 2328 sepsis cases and 2495 healthy controls for the TLR4 Asp299Gly variant. Eight studies provided genotype data for the rs4986791 polymorphism. The Asp299Gly variant showed a marginal protective effect in the allele (p = 0.08, odds ratio = 0.71) and dominant (p = 0.09, odds ratio = 0.71) genetic models, although it was not statistically significant. The trial sequential analysis indicated that further case–control studies are necessary to draw definitive conclusions about the TLR4 polymorphisms in sepsis. The TLR4 Asp299Gly variant may have a protective effect against sepsis. However, additional research with larger sample sizes across diverse populations is required to validate this finding. [ABSTRACT FROM AUTHOR]

To gain a clearer understanding of the relationship between venous leg ulcers (VLUs) and knee osteoarthritis (KOA), we performed a two‐sample, bidirectional Mendelian randomization (MR) analysis in this study. The present MR was carried out using summary data from publicly available genome‐wide association studies. After filtering single‐nucleotide polymorphism (SNP), we applied a variety of MR methods including inverse variance weighted (IVW), MR egger, weighted mode, and weighted median. IVW analysis revealed that the genetic association between VLUs and KOA was not significant (β = −0.017; SE 0.039; p = 0.658). In agreement with the IVW analysis, the findings of the weighted median estimator (β = −0.017; SE 0.052, p = 0.751), MR egger (β = 0.057; SE 0.084; p = 0.513), and weighted mode (β = 0.060; SE 0.078; p = 0.456) indicated the absence of a significant genetic association between VLUs and KOA. Furthermore, reverse causality analysis suggested a lack of genetic relationship between KOA and VLUs. In conclusion, the present MR study does not suggest a causal relationship or reverse causal relationship between VLUs and KOA. [ABSTRACT FROM AUTHOR]

Controlling the polymorphism of metal nanocrystals is a promising strategy for enhancing properties and discovering new phenomena. However, previous studies on Rh nanocrystals have focused on their thermodynamically stable face‐centered‐cubic (fcc) phase. Herein, a facile synthesis of Rh‐based nanocrystals featuring the metastable hexagonal close‐packed (hcp) phase is reported by using Ru seeds in their native hcp phase to template the deposition of Rh atoms. The success of such phase‐controlled synthesis relies on the templating effect promoted by the small lattice mismatch between Ru and Rh and the slow dropwise titration of the precursor at an elevated temperature, ensuring the layer‐by‐layer growth mode and thus the formation of a conformal hcp‐Rh shell. Faster injection rate of Rh(III) precursor leads to the formation of a rough Rh shell in the conventional fcc phase due to accelerated reaction kinetics. Considering both thermodynamic and kinetic aspects of this system, the hcp‐Rh phase is favored when the low surface energy from smooth overlayers balances the high bulk energy of the metastable phase, achieved through tight control of reaction rates and deposition patterns. These Ruhcp@Rhhcp core–shell nanocrystals demonstrate thermal stability up to 400 °C, while exhibiting higher catalytic activity toward ethanol oxidation reaction compared to Ruhcp@Rhfcc counterparts. [ABSTRACT FROM AUTHOR]

Russian wheat aphid (RWA, Diuraphis noxia Kurdjumov) is a highly invasive and destructive wheat pest evolving rapidly to overcome host resistance. Novel genes conferring resistance to multiple RWA biotypes are needed to sustain wheat production. The Iranian landrace PI 625139 is resistant to all five US RWA biotypes. To map the RWA resistance gene in PI 625139, both F2 and F2:3 populations were developed from cross PI 625139 × Smith's Gold, and the F2:3 population was evaluated for responses to five RWA biotypes, RWA1, RWA2, RWA3/7, RWA6, and RWA8. RWA assays identified a single gene in PI 625139, designated Dn625139, conditioning resistance to all five US RWA biotypes. Selective genotyping of a subset of F2 plants using genotyping‐by‐sequencing (GBS) revealed a set of single‐nucleotide polymorphism (SNP) markers on the short arm of chromosome 7D that are closely associated with RWA resistance. Kompetitive allele‐specific PCR (KASP) markers were developed from selected GBS‐SNPs in 7DS. Genetic analysis using the new KASP and simple sequence repeat (SSR) markers placed Dn625139 to a 2.6 cM interval. Dn625139 was 1.2 cM proximal to the KASP marker Stars‐KASP1007 (169.57 Mb) and 1.4 cM distal to the SSR marker Stars1039 (195.27 Mb) in the International Wheat Genome Sequencing Consortium (IWGSC) RefSeq v2.1 reference sequence, and co‐segregated with the SSR marker Stars1029 (180.82 Mb). Dn625139 is a valuable gene conferring resistance to multiple RWA biotypes, and the molecular markers developed in this study can facilitate its rapid introgression into locally adapted cultivars to enhance wheat RWA resistance. [ABSTRACT FROM AUTHOR]

The six major bovine milk proteins are encoded by highly polymorphic chromosomes. Genetic variation has become a topic of interest and controversy in recent years due to supposed adverse health effects, beginning with the A2 variant of β‐casein. The functional implications of genetic variants have been well characterised, specifically heat stability and coagulation (i.e. rennet and acid) properties of milk, which have found that the B variant of β‐casein, κ‐casein and β‐lactoglobulin are the most beneficial. Genetic variants of milk proteins provide considerable potential to create new dairy products to add value to milk. [ABSTRACT FROM AUTHOR]

Although farmed shrimp contribute to global food security and foreign exchange, the development of genomic resources such as single nucleotide polymorphisms for these shrimp is at slow pace. Public genomic resources like Genbank and Ensembl do not host polymorphism data for shrimp. Therefore, through analysis of the short RNA‐sequence reads generated on pooled‐individual samples, using the latest bioinformatics tools, this study documents data of single nucleotide polymorphisms in two shrimp species, Penaeus vannamei and Penaeus indicus, and presents these data in a searchable user‐friendly webtool, the dbVAST. The webtool also hosts the information about the possible effects that the variations could have on the functioning of the coded protein. This is the first open‐access SNP database of shrimp intended to benefit researchers and academicians by showcasing variations in shrimp transcripts. [ABSTRACT FROM AUTHOR]

Natural selection is known to favor specific gene combinations, thereby shaping the evolution of recombination rates, often through epistatic interactions. However, the dynamics of these interacting factors within natural populations remain poorly understood. In this study, we investigate the long‐term maintenance of a complex polymorphism involving linked, nonoverlapping chromosomal inversions in a natural population of Drosophila mediopunctata. Remarkably, even after 30 years—equivalent to roughly 340 generations—two major features have remained unexpectedly stable: the linkage disequilibrium (LD) between inversions, which deviates significantly from the theoretical prediction of decay, and a consistent seasonal cycle pattern of heterozygous excess and homozygous deficiencies. We explored the roles of recombination suppression, epistatic selection, and overdominance in maintaining this stability, examining their alignment with previously described patterns. Our findings reveal that moderate selection coefficients, such as s = 0.0407, are sufficient to maintain the observed LD for the most common haplotypes, albeit leading to an unstable equilibrium. Simulations further reveal that the introduction of overdominance stabilizes the system, enabling the long‐term persistence of this complex inversion polymorphism across various frequency scenarios. The stability of this system appears to hinge on a delicate balance between LD, recombination rates, and selective pressures, with overdominance playing a critical role. Our findings highlight the significance of epistatic interactions and selective pressures in shaping evolutionary pathways in natural populations and offer a compelling example of natural selection acting on a complex inversion polymorphism, providing valuable insights into the evolutionary dynamics governing inversion systems. [ABSTRACT FROM AUTHOR]

Colour polymorphic species often exhibit variation in morphology, physiology, and behaviour among morphs. In particular, dominance status may be signalled by the interaction between behaviour and colour morph. Behavioural traits associated with dominance include boldness, exploration, and aggression, which influence access to preferred habitat, territorial defence, and mate acquisition. In ectotherms, the social structure associated with morphs may result in the exploitation of structural niches differing in thermal quality. Hence, social interactions among morphs may generate concordant variation in thermal preference and environmental temperature. However, few studies have assessed thermal preference variation in colour polymorphic species and its covariation with behaviour. Doing so can provide insight into niche specialization and the maintenance of colour polymorphism in populations. Here, we investigated the patterns of covariation in boldness behaviour, exploratory behaviour, and thermal preference in the tree lizard, Urosaurus ornatus. We assessed trait variation between territorial and non‐territorial male morphs and between orange and yellow female morphs. Boldness and exploratory behaviour were repeatable in male U. ornatus and bolder individuals were significantly more likely to incur tail loss, a potential consequence of bold behaviour. Territorial male morphs were significantly bolder and more exploratory and preferred higher body temperatures with a narrower Tset than non‐territorial morphs. Female morphs did not vary in behavioural or thermal traits. This study highlights behavioural mechanisms that underly ecological niche segregation and variable habitat use between morphs in a colour polymorphic species. [ABSTRACT FROM AUTHOR]

Killer‐cell immunoglobulin‐like receptor (KIR) interactions with HLA class I have crucial roles in modulating NK cell function in response to viral infections. To explore the correlation between KIR/HLA and susceptibility to SARS‐CoV‐2 infection, we analysed polymorphism of KIR genes, haplotypes, HLA allotypes, and the interplay between KIR and HLA in individuals diagnosed with COVID‐19. Compared to a population control group, we observed a significantly increased frequency of KIR3DL3*00802 in the COVID‐19 group. When encoded by the HLA‐B gene, the frequency of HLA‐Bw4, a ligand for KIR3DL1, was at lower frequency in the COVID‐19 group. Additionally, significantly elevated frequencies of KIR‐Bx3, KIR3DL3*00301, 3DL3*048, and C1+HLA‐C were identified in the COVID‐19 group before multiple test correction, suggesting associations with susceptibility to SARS‐CoV‐2 infection. Our findings indicate that the KIR3DL3*00802 allele may be a high‐risk factor for SARS‐CoV‐2 infection, while Bw4 encoded by HLA‐B gene may confer protective effects against the infection. [ABSTRACT FROM AUTHOR]

Premise: Clines—or the geographic sorting of phenotypes across continual space—provide an opportunity to understand the interaction of dispersal, selection, and history in structuring polymorphisms. Methods: In this study, we combine field‐sampling, genetics, climatic analyses, and machine learning to understand a flower color polymorphism in the wide‐ranging desert annual Encelia farinosa. Results: We find evidence for replicated transitions in disk floret color from brown to yellow across spatial scales, with the most prominent cline stretching ~100 km from southwestern United States into México. Because population structure across the cline is minimal, selection is more likely than drift to have an important role in determining cline width. Conclusions: Given that the cline aligns with a climatic transition but there is no evidence for pollinator preference for flower color, we hypothesize that floret color likely varies as a function of climatic conditions. [ABSTRACT FROM AUTHOR]

Summary Dwarf plant architecture facilitates dense planting, and increased planting densities boost the maize yield. However, breeding applications of dwarfing materials for maize are currently limited. There is an urgent need remove the obstacles to applying dwarf resources. Here, we innovated a new method to add a novel maize dwarf germplasm through the distant hybridization of Maize–Tripsacum–Teosinte allopolyploid (MTP) with maize. We identified ten independent dwarf families with unique characteristics. Five germplasms in our library were controlled by their respective dwarf genes. However, no allele was controlled by Br2. Subsequently, d024 in the library was successfully fine mapped, revealing its linkage to indel‐4 in ZmCYP90D1. The indel‐4 polymorphism regulates the expression of ZmCYP90D1 and is controlled by an upstream transcription factor (ZmBES1/BZR1‐5). The indel‐4 of ZmCYP90D1 allele, which reduces plant height, originated from Tripsacum, a wild variety of maize. However, d024 exhibits sensitivity to brassinosteroids (BRs), with lower castasterone levels in the internodes than that in the wild type. Furthermore, ZmCYP90D1 interacted with ZmFDXs and ZmNAD(P)H to positively regulate the downstream BR synthesis pathway. Additionally, we showed that introgressing the indel‐4 of the Tripsacum allele into modern hybrids ensures yield potential and improves the harvest index under high‐density conditions. Overall, as we begin to manufacture highly engineered dwarf materials using the MTP, this approach will solve the problems faced by corn dwarfs. [ABSTRACT FROM AUTHOR]

Background and Aim: This study aimed to clarify whether several single‐nucleotide polymorphisms (SNPs)‐related chronic pancreatitis such as carboxypeptidase A1 (CPA1), carboxypeptidase B1 (CPB1), Gamma‐glutamyltransferase 1 (GGT1), G‐protein‐coupled receptor Class C Group 6 Member A (GPRC6A), and serine protease inhibitor, Kazal type 1 (SPINK‐1) genotypes were associated with clinical characteristics of patients with intraductal papillary mucinous neoplasm (IPMN) and worrisome features of IPMN. Methods: We enrolled 100 patients with IPMN and 116 patients as a control. Serum p‐amylase, lipase, trypsin, phospholipase A2 (PLA2), and elastase‐1 levels were measured. An Olympus EUS (GF‐UCT 260) was used to perform endosonography in 100 patients with IPMN. Total EUS score was evaluated using endosonography. DNA was isolated from the duodenal tissue using a commercial system and polymerase chain reaction (PCR) was performed on 7500 Fast PCR System. Results: There were no associations between glucose tolerances, lipid levels and genotypes of CPA1, GGT1, GPRC6A, and SPINK‐1 in patients with IPMN. CPA1 genotype was significantly associated with the pathophysiology of IPMN. Then, GGT1 genotype was also significantly associated with EUS total score and the size of cyst more than 20 mm and more than 30 mm as one of worrisome features of IPMN. Conclusion: Genotypes of carboxypeptidase A1 and gamma‐glutamyltransferase 1 may be useful tools for the diagnosis and the predictor of worrisome features of IPMN. [ABSTRACT FROM AUTHOR]

We designed a new cyanine dye 1, with two pedant rod‐like groups, capable of forming two distinct two‐dimensional (2D) supramolecular polymorphs in methylcyclohexane; an H‐type aggregate (Agg‐H2) and a J‐type aggregate (Agg‐J). Importantly, these two polymorphs were not accessed through polymerization events, and instead through the thermal transformation of a third particle‐like polymorph (Agg‐H1) formed by the anti‐cooperative assembly of 1. While Agg‐H2 is generated upon cooling the solution of Agg‐H1 by a thermoreversible polymorph transition, the Agg‐J was obtained through a hidden pathway by combining sonication and cooling to the Agg‐H1 solution. This is the first report on the obtention of H‐ and J‐type cyanine polymorphs that in turn could be isolated in solid‐state to render two new 2D photoactive materials. This paper unveils new strategies for designing 2D supramolecular polymers using calamitic residues, but also undercovers relevant aspects of pathway complexity and polymorph transitions that might be crucial for developing novel photonic systems [ABSTRACT FROM AUTHOR]

ABSTRACT Background and Aim Location Taxon Results Main Conclusions Colour polymorphic populations constitute excellent model systems for testing ecological and evolutionary hypotheses, as alternate colourations are associated with differences in various biological, behavioural and life‐history traits. Melanism is the most common and most obvious form of polymorphism. In reptiles in general (and snakes in particular), thermal melanism has been a popular hypothesis used to explain the appearance of black individuals. It suggests that a trade‐off exists between superior thermoregulation and reduced protection through the loss of crypsis. Surprisingly, despite the growing body of literature available, to date, there are only two qualitative reviews on the evolutionary significance of melanism in reptiles and no quantitative synthesis. We conducted the first systematic review and meta‐analysis summarising the current knowledge on melanism in polymorphic terrestrial snakes and synthesised the evidence for an adaptive advantage of the melanistic morph.Northern Hemisphere.Polymorphic terrestrial snakes.Mean prevalence of melanism is 31% with no significant differences between species. Annual precipitation was a significant moderator of melanism prevalence. Our results revealed no significant differences in odds ratios of melanism between sexes or in mean body size.Environmental plasticity can be considered the primary cause of melanism, possibly as a result of seasonal climatic variations, a result corroborated by the formal meta‐analysis conducted. Conclusions from the meta‐analysis are that melanism in snakes follows Gloger's rule, as is the case in birds and mammals, and as opposed to the thermal melanism hypothesis. Further, our findings do not lend support for other predictions from the thermal melanism hypothesis, such as skewed frequency of melanistics in favour of males or females, or larger body sizes in black individuals. Our results hold implications for the future diversity of animal populations, as climate change is predicted to decrease the degree of colour variation. [ABSTRACT FROM AUTHOR]

Two‐coordinate coinage metal complexes have been exploited for various applications. Herein, a new donor‐metal‐acceptor (D–M–A) complex PZI‐Au‐TOT, using bulky pyrazine‐fused N‐heterocyclic carbene (PZI) and trioxytriphenylamine (TOT) ligands, was synthesized. PZI‐Au‐TOT displays decent thermally activated delayed fluorescence (TADF) with a quantum yield of 93 % in doped film. The crystals of PZI‐Au‐TOT show simultaneous TADF, polymorphism, and linearly polarized luminescence (LPL). The polymorph‐dependent emission properties with widely varied peaks from 560 to 655 nm are attributed to different packing modes in terms of isolated monomers, discrete π–π stacked dimers or dimer PLUS. Two well‐defined microcrystals of PZI‐Au‐TOT exhibit linearly polarized thermally activated delayed fluorescence with a degree of polarization up to 0.64. This work demonstrates that the molecular rotational flexibility of D–M–A type complexes endows an integration of multiple functions into one complex through manipulation of supramolecular aggregation. This type of complexes is expected to serve as a versatile platform for the fabrication of crystal materials for advanced photonic applications. [ABSTRACT FROM AUTHOR]

Summary Plant chemodiversity, the diversity of plant‐specialized metabolites, is an important dimension of biodiversity. However, there are so far few mathematical models to test verbal hypotheses on how chemodiversity evolved. Here, we develop such a model to test predictions of five hypotheses: the ‘fluctuating selection hypothesis’, the ‘dominance reversal hypothesis’, the interaction diversity hypothesis, the synergy hypothesis, and the screening hypothesis. We build a population genetic model of a plant population attacked by herbivore species whose occurrence fluctuates over time. We study the model using mathematical analysis and individual‐based simulations. As predicted by the ‘dominance reversal hypothesis’, chemodiversity can be maintained if alleles conferring a defense metabolite are dominant with respect to the benefits, but recessive with respect to costs. However, even smaller changes in dominance can maintain polymorphism. Moreover, our results underpin and elaborate predictions of the synergy and interaction diversity hypotheses, and, to the extent that our model can address it, the screening hypotheses. By contrast, we found only partial support for the ‘fluctuating selection hypothesis’. In summary, we have developed a flexible model and tested various verbal models for the evolution of chemodiversity. Next, more mechanistic models are needed that explicitly consider the organization of metabolic pathways. [ABSTRACT FROM AUTHOR]

Wheat stem rust (caused by Puccinia graminis f.sp. tritici) is a damaging disease widespread in all grain‐producing regions of the world. In this work, the effectiveness of Sr genes was analysed under field conditions in the southern region of Russia (Krasnodar Krai, Stavropol Krai and Rostov Oblast) during 2016‐2021. The data were obtained using a set of 46 isogenic lines and varieties with artificial inoculation. The Sr31 gene proved absolute effectiveness in the field. Effective (1R–10R) Sr genes were the following: 5, 12, 35 and 37; moderately effective (10MR–30MR) Sr genes: 1, 6, 9g, 10, 11, 13, 14, 15, 20, 22, 23, 24, 25, 32, 33, 38 and WLD. Lines with Sr genes 7a, 7b, 8a, 8b, 9a, 9b, 9d, 9e, 9f, 16, 17, 19, 21, 26, 27, 29, 30, 36, 39, 40, 44, Dp2, Gt and Tmp were ineffective in the adult plant phase (30MS–70S). Polymorphism of infection types and disease severity was noted for most of these lines in different years. Ongoing analysis of the efficiency of Sr genes in the region is important to prevent the risk of epidemics, and lines with stem rust resistance genes that have shown efficiency can be used as donors in breeding programmes. [ABSTRACT FROM AUTHOR]

The competition between surficial and volumetric diffusion during the sintering process for ceramic polymorphism at different sintering temperatures is worth deeply exploring. In the current work, various sintering cases of mixed TiO2 nanoparticles with rutile and anatase types were investigated and the effects of crystalline phase, sintering temperature, and particle size on the sintering process were systematically investigated. The difference in thermodynamic stability and surficial activity of the crystalline phase could promote the decomposition and densification of the nanoparticles. Comparing the mixed‐phase sintering process at different sintering temperatures, the results showed that the particle binding process at low temperature relied mainly on surficial diffusion, however, volumetric diffusion played a crucial role at high temperature. The internal occurrence of volumetric diffusion inhibited the surficial diffusion, resulting in a smaller diameter of the sintering neck and a different sintering rate. In the case of sintering three nanoparticles with rutile and anatase types, it could be found that the decomposition of nanoparticles is more uniform in mixed‐phase sintering at high temperatures and the sintering rate is not significantly influenced by the sintering temperature. This work demonstrates the advantage of a mixed‐phase sintering strategy for TiO2 nanoparticles, which could provide insight into ceramic materials with polymorphism. [ABSTRACT FROM AUTHOR]

Even seemingly homogeneous on the surface, the oceans display high environmental heterogeneity across space and time. Indeed, different soft barriers structure the marine environment, which offers an appealing opportunity to study various evolutionary processes such as population differentiation and speciation. Here, we focus on Amphiprion clarkii (Actinopterygii; Perciformes), the most widespread of clownfishes that exhibits the highest colour polymorphism. Clownfishes can only disperse during a short pelagic larval phase before their sedentary adult lifestyle, which might limit connectivity among populations, thus facilitating speciation events. Consequently, the taxonomic status of A. clarkii has been under debate. We used whole‐genome resequencing data of 67 A. clarkii specimens spread across the Indian and Pacific Oceans to characterize the species' population structure, demographic history and colour polymorphism. We found that A. clarkii spread from the Indo‐Pacific Ocean to the Pacific and Indian Oceans following a stepping‐stone dispersal and that gene flow was pervasive throughout its demographic history. Interestingly, colour patterns differed noticeably among the Indonesian populations and the two populations at the extreme of the sampling distribution (i.e. Maldives and New Caledonia), which exhibited more comparable colour patterns despite their geographic and genetic distances. Our study emphasizes how whole‐genome studies can uncover the intricate evolutionary past of wide‐ranging species with diverse phenotypes, shedding light on the complex nature of the species concept paradigm. [ABSTRACT FROM AUTHOR]

Colour signals play pivotal roles in different communication systems, and the evolution of these characters has been associated with behavioural ecology, integumentary production processes and perceptual mechanisms of the species involved. Here, we present the first insight into the molecular and histological basis of skin colour polymorphism within a miniaturized species of pumpkin toadlet, potentially representing the lowest size threshold for colour polytypism in tetrapods. Brachycephalus actaeus exhibits a coloration ranging from cryptic green to conspicuous orange skin, and our findings suggest that colour morphs differ in their capability to be detected by potential predators. We also found that the distribution and abundance of chromatophores are variable in the different colour morphs. The expression pattern of coloration related genes was predominantly associated with melanin synthesis (including dct, edn1, mlana, oca2, pmel, slc24a5, tyrp1 and wnt9a). Up‐regulation of melanin genes in grey, green and brown skin was associated with higher melanophore abundance than in orange skin, where xanthophores predominate. Our findings provide a significant foundation for comparing and understanding the diverse pathways that contribute to the evolution of pigment production in the skin of amphibians. [ABSTRACT FROM AUTHOR]

In flying animals, wing morphology is typically assumed to influence flight behaviours. Whether seasonal polymorphism in butterfly morphology is linked to adaptive flight behaviour remains unresolved. Here, we compare the flight behaviours and wing morphologies of the spring and summer forms of two closely related butterfly species, Pieris napi and P. rapae. We first quantify three‐dimensional flight behaviour by reconstructing individual flight trajectories using stereoscopic high‐speed videography in an experimental outdoor cage. We then measure wing size and shape, which are characteristics assumed to influence flight behaviours in butterflies. We show that seasonal, but not interspecific, differences in flight behaviour might be associated with divergent forewing shapes. During spring, Pieris individuals are small and have elongated forewings, and generally fly at low speed and acceleration, while having a high flight curvature. On the contrary, summer individuals are larger and exhibit rounded forewings. They fly at high speed and acceleration, while having high turning acceleration and advance ratio. Our study provides one of the first quantitative pieces of evidence of different flight behaviours between seasonal forms of two Pieris butterfly species. We discuss the possibility that this co‐divergence in flight behaviour and morphology is an adaptation to distinct seasonal environments. Properly identifying the mechanisms underpinning such divergence, nonetheless, requires further investigations to disentangle the interacting effects of microhabitats, predator community, parasitoid pressure and behavioural differences between sexes. [ABSTRACT FROM AUTHOR]

Understanding how languages change is important not only for the reconstruction of protolanguages and for estimating diversification dates (i.e. the dates when languages split), but also for the inference of evolutionary trees (or phylogenetic networks) of language families. We propose a parametric model of language change that addresses lexical polymorphism (two or more words for a given basic meaning) based on what is known about how languages change. Under our model, changes of state in lexical characters occur only due to semantic shift or borrowing, leading to (potentially brief) periods in which polymorphism is present. Across a wide range of model conditions, we find that a simple and natural modification to the maximum parsimony (MP) criterion (which seeks the tree with the fewest number of changes) to allow it to handle polymorphic characters has the best accuracy, substantially improving on well‐known Bayesian methods based on appearances and disappearances of words. We also provide a new analysis of Indo–European that takes polymorphism into account, finding support for a previous tree (Nakhleh et al., 2006) and a new tree that differs from the previous tree in the relationship between Italo‐Celtic and Tocharian. [ABSTRACT FROM AUTHOR]

Marbling is one of the most important beef quality traits. An association between a non‐synonymous variant located in EGFLAM (EGF‐like fibronectin and laminin G) and marbling in Hanwoo cattle has recently been published. We therefore investigated the association between this SNP (rs109436056 SNP) and marbling in Limousin cattle. A total of 355 animals were phenotyped for marbling and genotyped for this SNP. Significant association (p < 0.05) was observed, in which genotype CC exhibited higher marbling. This SNP could be used for the genetic improvement of marbling in Limousin cattle. [ABSTRACT FROM AUTHOR]

The article proposes to conserve the name Stellaria graminea (Caryophyllaceae) with a conserved type. Stellaria graminea is a perennial herb found in Eurasia, North America, and New Zealand. It is a diploid-tetraploid species complex with a triploid cytotype. The article suggests that Stellaria graminea is a good model for studying the association between sexual polymorphism and whole genome duplication. The article also discusses the protologue of Stellaria graminea and proposes a conserved type for the name. Rejecting the proposal would result in the name Stellaria graminea becoming a synonym of Arenaria purpurascens. [Extracted from the article]

Evaluating fish feeding behaviours is imperative to understanding prey resource use in the field. Previous work on fish feeding has taken place almost exclusively in a laboratory setting, which may impose artificial restrictions. Thus, we aimed to evaluate the constraints the captive setting places on fish feeding behaviours.We recorded polymorphic (littoral and pelagic) bluegill sunfish (Lepomis macrochirus) feeding in the laboratory and the field using a high‐speed camera and underwater cameras. Following successful strikes video events, were digitised using ImageJ (laboratory) and Argus (field).Gape velocity, ram velocity, and body deceleration were higher in the field than in captive fish. Significantly greater gape velocity in field fish suggests that these fish feed with greater suction pressure than captive fish. Prey effects were detected, as brine shrimp feeding events were characterised by slower gape and ram velocities and a smaller gape. Feeding events on brine shrimp in the field were similar to feeding events on worms in the laboratory suggesting an artefact of training.These results indicate that feeding behaviours measured in the laboratory may not be representative of feeding behaviours in the wild. Further consideration of organismal performance and laboratory constraints should be taken in future functional studies. [ABSTRACT FROM AUTHOR]

Surprisingly, little is known about how eco‐evolutionary feedback loops affect trait dynamics within a single population. Polymorphisms of discrete alternative phenotypes present ideal test beds to investigate this, as the alternative phenotypes typically exhibit contrasting demographic rates mediated through frequency or density dependence, and are thus differentially affected by selection.Alternative reproductive tactics (ARTs), like male fighters and sneakers, are an extreme form of discrete phenotype expression and occur across many taxa. Fighters possess weapons for male–male competition over access to mates, whereas sneakers are defenceless but adopt tactics like female‐mimicking. Because fighters in some species mortally injure conspecifics, this raises the question whether fighter expression can feed back to affect population size and structure, thereby altering the selection gradient and evolutionary dynamics of ART expression in an eco‐evolutionary feedback loop.Here, we investigated how the eco‐evolutionary feedback loop between fighter expression and population size and structure affects the evolution and maintenance of ARTs. We introduced intraspecific killing by fighters in a two‐sex, two‐ART population model parameterized for the male dimorphic bulb mite (Rhizoglyphus robini) that includes life‐history differences between the ARTs and a mating‐probability matrix analogous to the classic hawk–dove game.Using adaptive dynamics, we found that the intraspecific killing by fighters can extend the range of life‐history parameter values under which ARTs evolve, because fighters that kill other fighters decrease fighter fitness. This effect can be nullified when benefits from killing are incorporated, like increased reproduction through increased energy uptake.The eco‐evolutionary feedback effects found here for a dimorphic trait likely also occur in other fitness‐related traits, such as behavioural syndromes, parental care and niche construction traits. Current theoretical advances to model eco‐evolutionary processes, and empirical steps towards unravelling the underlying drivers, pave the way for understanding how selection affects trait evolution in an eco‐evolutionary feedback loop. Life cycle links between killing and copulating highlight the importance of studying eco‐evolutionary interactions. Using a theoretical model, the authors show how the intraspecific killing of conspecifics affects the ecological dynamics of a population, which feeds back to influence the evolution of what reproductive strategies males employ to gain access to females. [ABSTRACT FROM AUTHOR]

Aim: The maintenance of polymorphisms is often explained by sexual selection. However, natural selection may also constrain morphs to particular locations, causing geographical variation in morph diversity. In many well‐known polymorphic organisms in which the relevance of sexual selection on the maintenance of polymorphisms is widely supported, the role of environmental factors has been poorly studied. Here, we adopted a population‐level approach to assess the extent to which geographical variation in climate explains morph composition in a colour polymorphic lizard. We predict that rare morphs are more environmentally constrained than common morphs. Location: Eastern Pyrenees, Western Europe. Taxon: Podarcis muralis (Lacertidae). The species shows up to five discrete colour morphs: white (W), orange (O), white‐orange (WO), yellow (Y) and yellow‐orange (YO). Populations strongly vary in morph composition. Methods: We modelled the realised niche of each morph and the whole species with Maxent, Bioclim, and Domain, considering 110 localities over a relatively small but environmentally heterogeneous area. Morph ranges were compared to identify differences among their realised niches and local morph frequencies were interpolated to detect intra‐morph geographical variations beyond the mere presence of morphs. Results: Differences between morph distributions were mainly associated to temperature seasonality and annual precipitation. While W, O, and WO morphs were found along the whole environmental range of the species, Y and YO morphs were restricted to a subset of the environmental conditions suitable for the species, namely high temperature seasonality and relatively high precipitation. Local frequencies of common morphs also differ among localities, the W morph being more frequent at lower altitudes than the O and WO morphs, which are more locally abundant at higher altitudes. Main conclusions: We found a remarkable geographical relationship between climate and local morph composition that suggests environmentally dependent selection acting in a different way on common and rare morphs, most likely in interaction with sexual selection. [ABSTRACT FROM AUTHOR]

1. Functional wing polymorphism in insects is an intriguing topic, especially with respect to the adaptive advantage of each wing morph. The common pygmy grasshopper in Germany, Tetrix subulata, displays wing polymorphism skewed towards macropterous (LW) individuals capable of flight. Furthermore, T. subulata is known to undergo adult diapause in winter and reproduce in spring. 2. Morphometric and biochemical parameters were examined in field‐collected grasshoppers during autumn and spring to obtain a ‘snapshot’ from the same/one cohort of grasshoppers in the wild. 3. Flight muscles are largely reduced in brachypterous (SW) specimens, whereas they are well developed in LW individuals. Body mass measurements indicated gain in female T. subulata in spring, especially in LW morphs, which could be attributed to increased reproductive activity (egg production). 4. Metabolic fuel in haemolymph is differentially distributed in autumn: the concentration of lipids is highest in males, while carbohydrates are most abundant in LW specimens. The metabolic data imply that dispersal in T. subulata is predominantly in autumn, by flight in the case of LW specimens and by hopping/walking in males. 5. The season seems to be an important factor for the reproductive versus dispersal trade‐off in this species. Moreover, this study shows that morphological differences in T. subulata individuals are reflected in physiological differences that may ultimately affect behaviour and ecology. [ABSTRACT FROM AUTHOR]

Dispersal (i.e. movement from a natal or breeding site to another breeding site) is a central process in ecology and evolution as it affects the eco‐evolutionary dynamics of spatially structured populations. Dispersal evolution is regulated by the balance between costs and benefits, which is influenced by the individual phenotype (i.e. phenotype‐dependent dispersal) and environmental factors (i.e. condition‐dependent dispersal). Even though these processes have been extensively studied in species with simple life cycles, our knowledge about these mechanisms in organisms displaying complex life cycles remains fragmentary. In fact, little is specifically known about how the interplay between individual and environmental factors may lead to alternative dispersal strategies that, in turn, lead to the coexistence of contrasted site fidelity phenotypes. In this paper, we examined breeding dispersal in a pond‐breeding amphibian, the great crested newt Triturus cristatus, within usual walking distances for a newt. We took advantage of recent developments in multi‐event capture–recapture models and used capture–recapture data (946 newts marked) collected in a spatially structured population occupying a large pond network (73 ponds). We showed a high rate of breeding site infidelity (i.e. pond use) and the coexistence of two dispersal phenotypes, namely, a highly pond faithful phenotype and a dispersing phenotype. Individuals that were site faithful at time t – 1 were therefore more likely to remain site faithful at time t. Our results also demonstrated that the probability that individuals belong to one or the other dispersal phenotypes depended on environmental and individual factors. In particular, we highlighted the existence of a dispersal syndrome implying a covariation pattern among dispersal behavior, body size, and survival. Our work opens new research prospects in the evolution of dispersal in organisms displaying complex life cycles and raises interesting questions about the evolutionary pathways that contribute to the diversification of movement strategies in the wild. [ABSTRACT FROM AUTHOR]

Abstract: The swallowtail butterfly Papilio polytes is known for its striking resemblance in wing pattern to the toxic butterfly Pachliopta aristolochiae and is a focal system for the study of mimicry evolution. Papilio polytes females are polymorphic in wing pattern, with mimetic and nonmimetic forms, while males are monomorphic and nonmimetic. Past work invokes selection for mimicry as the driving force behind wing pattern evolution in P. polytes. However, the mimetic relationship between P. polytes and P. aristolochiae is not well understood. In order to test the mimicry hypothesis, we constructed paper replicas of mimetic and nonmimetic P. polytes and P. aristolochiae, placed them in their natural habitat, and measured bird predation on replicas. In initial trials with stationary replicas and plasticine bodies, overall predation was low and we found no differences in predation between replica types. In later trials with replicas mounted on springs and with live mealworms standing in for the butterfly's body, we found less predation on mimetic P. polytes replicas compared to nonmimetic P. polytes replicas, consistent with the predator avoidance benefits of mimicry. While our results are mixed, they generally lend support to the mimicry hypothesis as well as the idea that behavioral differences between the sexes contributed to the evolution of sexually dimorphic mimicry. [ABSTRACT FROM AUTHOR]

Abstract: Although predation is commonly thought to exert the strongest selective pressure on coloration in aposematic species, sexual selection may also influence coloration. Specifically, polymorphism in aposematic species cannot be explained by natural selection alone. Males of the aposematic wood tiger moth (Arctia plantaginis) are polymorphic for hindwing coloration throughout most of their range. In Scandinavia, they display either white or yellow hindwings. Female hindwing coloration varies continuously from bright orange to red. Redder females and yellow males suffer least from bird predation. White males often have higher mating success than yellow males. Therefore, we ask whether females can discriminate the two male morphs by colour. Males approach females by following pheromone plumes from a distance, but search visually at short range. This raises the questions whether males discriminate female coloration and, in turn, whether female coloration is also sexually selected. Using electroretinograms, we found significantly larger retinal responses in male than female A. plantaginis, but similar spectral sensitivities in both sexes, with peaks in the UV (349 nm), blue (457 nm) and green (521 nm) wavelength range. According to colour vision models, conspecifics can discriminate white and yellow males as separate morphs, but not orange and red females. For moths and birds (Cyanistes caeruleus), white males are more conspicuous against green and brown backgrounds, mostly due to UV reflectivity, and red females are slightly more conspicuous than orange females. The costly red coloration among females is likely selected by predator pressure, not by conspecifics, whereas male colour polymorphism is probably maintained, at least partly, by the opposing forces of predation pressure favouring yellow males, and female preference for white males. Whether or not the preference for white males is based on visual cues requires further testing. The evolution of polymorphic aposematic animals can be better understood when the visual system of the species and their predators is taken into consideration. A plain language summary is available for this article. [ABSTRACT FROM AUTHOR]

Abstract: Isolation between species, or taxa sharing a common lineage, depends primarily on the relative strengths of various reproductive barriers. Previous studies on reproductive isolation between orchids emphasized mechanical and ethological barriers in flowers of species showing food and/or sexual mimicry. In this study, we investigated and quantified a series of prepollination and postpollination barriers between pink and white forms of Spiranthes sinensis sl, a nectar‐secreting complex. We generated ML trees based on trnS‐G and matK to explore phylogenetic relationships in this species complex. Spiranthes sinensis sl segregated from some other congeners, but the white form constituted a distinct clade in relation to the pink form. The white form secreted 2‐Phenylethanol as it is a single‐scent compound and was pollinated almost exclusively by native, large‐bodied Apis cerana and Bombus species (Apidae). Apis cerana showed a high floral constancy to this form. The scentless, pink form was pollinated primarily by smaller bees in the genera Ceratina (Apidae), and members of the family Halictidae, with infrequent visits by A. cerana and Bombus species. Fruit set and the production of large embryos following interform pollination treatments were significantly lower compared to intraform pollination results for the white form. Our results suggested that pollinator isolation, based on color and scent cues, may result in greater floral constancy in white populations when both forms are sympatric as two different, guilds of pollinators forage selectively preventing or reducing prospective gene flow. Postpollination barriers appear weaker than prepollination barriers but they also play a role in interform isolation, especially in the white form. Our findings suggest that floral color forms in S. sinensis do not represent an unbalanced polymorphism. Interpretations of the evolutionary status of these forms are discussed. [ABSTRACT FROM AUTHOR]

Abstract: The scale‐eating cichlid fish Perissodus microlepis is a textbook example of bilateral asymmetry due to its left or right‐bending heads and of negative frequency‐dependent selection, which is proposed to maintain this stable polymorphism. The mechanisms that underlie this asymmetry remain elusive. Several studies had initially postulated a simple genetic basis for this trait, but this explanation has been questioned, particularly by reports observing a unimodal distribution of mouth shapes. We hypothesize that this unimodal distribution might be due to a combination of genetic and phenotypically plastic components. Here, we expanded on previous work by investigating a formerly identified candidate SNP associated to mouth laterality, documenting inter‐individual variation in feeding preference using stable isotope analyses, and testing their association with mouth asymmetry. Our results suggest that this polymorphism is influenced by both a polygenic basis and inter‐individual non‐genetic variation, possibly due to feeding experience, individual specialization, and intraspecific competition. We introduce a hypothesis potentially explaining the simultaneous maintenance of left, right, asymmetric and symmetric mouth phenotypes due to the interaction between diverse eco‐evolutionary dynamics including niche construction and balancing selection. Future studies will have to further tease apart the relative contribution of genetic and environmental factors and their interactions in an integrated fashion. [ABSTRACT FROM AUTHOR]

Crucial for the long-term survival of wild populations is their ability to fight diseases. Disease outbreaks can lead to severe population size reductions, which makes endangered and reintroduced species especially vulnerable. In vertebrates, the major histocompatibility complex (MHC) plays an important role in determining the immune response. Species that went through severe bottlenecks often show very low levels of genetic diversity at the MHC. Due to the known link between the MHC and immune response, such species are expected to be at particular risk in case of disease outbreaks. However, so far, only few studies have shown that low MHC diversity is correlated with increased disease susceptibility in species after severe bottlenecks. We investigated genetic variation at the MHC and its correlations with disease resistance and other fitness-related traits in Alpine ibex (Capra ibex), a wild goat species that underwent a strong bottleneck in the last century and that is known to have extremely low genetic variability, both genome-wide and at the MHC. We studied MHC variation in male ibex of Gran Paradiso National Park, the population used as a source for all postbottleneck reintroductions. We found that individual MHC heterozygosity (based on six microsatellites) was not correlated with genome-wide neutral heterozygosity. MHC heterozygosity, but not genome-wide heterozygosity, was positively correlated with resistance to infectious keratoconjunctivitis and with body mass. Our results show that genetic variation at the MHC plays an important role in disease resistance and, hence, should be taken into account for successfully managing species conservation. [ABSTRACT FROM AUTHOR]

Abstract: Polymorphic populations are often considered as intermediate stages of speciation. Bluegill sunfish (Lepomis macrochirus) from Lake Waban, Wellesley, MA have diverged into two ecomorphs based on their diet, occupied habitat and morphology. Littoral bluegills are generalist feeders that consume a variety of aquatic invertebrates. Pelagic bluegills feed primarily on Daphnia. We aimed to understand if suction pressure generation, prey capture behaviors and pharyngeal jaw morphology differed between the littoral and pelagic ecomorphs feeding on three prey types. Littoral and pelagic bluegills showed similar feeding kinematics and peak pressure, however, significant differences were observed among prey types within an ecomorph. Feeding events on brine shrimp were slower and accompanied by less negative pressure for both ecomorphs. Littoral bluegills varied their use of ram among prey types, however, pelagic bluegills (zooplankton specialists) did not. Similar to previous studies, when presented with different prey items both dietary generalists and specialists varied equally in most aspects of their feeding behaviors. However, pelagic bluegills (dietary specialists) did not vary in their approach behaviors. Despite the lack of differences in trophic morphology among the individuals sampled here, the prey approach behaviors of dietary specialists appears to be fixed in pelagic bluegills. This result deemphasizes the importance of suction during feeding and places more importance on prey approach behaviors. [ABSTRACT FROM AUTHOR]

Abstract: Recent developments in sexual selection theory suggest that on their own, mate preferences can promote the maintenance of sexual trait diversity. However, how mate preferences constrain the permissiveness of sexual trait diversity in different environmental regimes remains an open question. Here, we examine how a range of mate choice parameters affect the permissiveness of sexual trait polymorphism under several selection regimes. We use the null model of sexual selection and show that environments with strong assortative mating significantly increase the permissiveness of sexual trait polymorphism. We show that for a given change in mate choice parameters, the permissiveness of polymorphism changes more in environments with strong natural selection on sexual traits than in environments with weak selection. Sets of nearly stable polymorphic populations with weak assortative mating are more likely to show accidental divergence in sexual traits than sets of populations with strong assortative mating. The permissiveness of sexual trait polymorphism critically depends upon particular combinations of natural selection and mate choice parameters. [ABSTRACT FROM AUTHOR]

ABSTRACT: The northern subspecies of the salt marsh harvest mouse (Reithrodontomys raviventris halicoetes) is morphologically similar to the western harvest mouse (R. megalotis) with which it co‐occurs in the Suisun Marsh, California, USA, and therefore they are difficult to distinguish in the field. The salt marsh harvest mouse is a federal and California state‐listed endangered species, whereas the western harvest mouse has no special status. Thus, our objective was to identify the most effective field metrics that distinguish the species. First we identified a barcode of life and restriction fragment length polymorphism approach for genetically distinguishing between the species. Then we performed univariate tests to examine variation in standard external morphological traits within and between species, and found that differences between species were confounded by sex and age. We then used discriminant function analysis and multiple logistic regression (MLR) to find combinations of characters that resulted in the highest percentages of correct classification based on a data set of individuals with genetically verified species identity. The best model (MLR) correctly classified 90.1 ± 3.5% ( x ¯ ± SD) of individuals, though all approaches performed relatively poorly with smaller, ostensibly younger, mice. Therefore, tail length, body length, and tail diameter, if treated in a comprehensive multivariate context, can yield substantial accuracy for distinguishing between coexisting northern salt marsh and western harvest mice. © 2018 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Abstract: A growing body of literature is recognizing that males may also play a role in the mating process by behaving non‐randomly toward potential female mates during courtship. In numerous species, discrete color polymorphisms in males are inferred to represent alternative mating tactics, which often correspond with concomitant asymmetries in ecology and behavior. In terms of their mating behavior, these ecological outcomes of a color polymorphism should affect a morph's likelihood and frequency of encountering females in a population, possibly favoring the evolution of morph‐specific mating preferences. Knowledge of how male morphs contribute to a species’ overall mating dynamics will improve our understanding of how sexual selection shapes phenotypic diversity in color polymorphic systems. We conducted a mate choice experiment to evaluate the extent and morph specificity of non‐random mating preferences by male ornate tree lizards, Urosaurus ornatus. We observed the behavior of blue and yellow males in an experimental arena in response to a choice between an orange or yellow female. We found that blue males preferred yellow females over orange females, and although yellow males visited females more often than blue males overall, their attention was not morph‐specific. Given male morph differences in choosiness, and their differences in social dominance, we conclude that female throat color may be partly under sexual selection in U. ornatus. However, a lack of concordance between male and female mating preferences (drawn from an earlier study) suggests that overall mating dynamics may serve to maintain, rather than enhance, color morph differences in this species. [ABSTRACT FROM AUTHOR]

Abstract: Territoriality evolves when the benefits gained from exclusive access to limited resources exceed the costs of defence. Sometimes animals evolve distinct morphs, that may reflect different capability, and in some territorial species of lizards the polymorphism is associated to alternative strategies, both for reproductive efficiency and territorial dominance. It is known that normally larger males are more aggressive and are able to defend a larger area and for longer than small males; in fact this dynamic is widespread in many animal species including the genus Podarcis. The aim of our study was to test which factors determine the outcome of fighting in the strongly territorial Italian ruin lizard, Podarcis siculus, using two types of contests: (1) resident versus intruder and (2) in a neutral arena. Furthermore, because these lizards are characterized by strong ventral colour variability, usually restricted to jaws and throat, we wanted to investigate if coloured lizards have higher chances at winning than white lizards. The results showed that the fight's result was significantly influenced by the state of residence, while the colour had no effect; instead, the snout to vent length difference between opponents had significant influence on the outcome in the neutral arena. Our results suggest that, in this lizard, both the size and the state of residency, no matter of colour, play an important role to determine the outcome of a fight, however, highly depending on the contest. We think that P. siculus should be object of future studies, focusing on behavioural and ecological aspects, even considering the occurrence of different colours within and among populations. [ABSTRACT FROM AUTHOR]