Physiological constraints on colouration have been widely reported; especially in birds, which trade-off antioxidant responses against colourful costly signals. One female extended phenotypic trait, which might also highlight important physiological trade-offs, is the pigmentation of their eggshells. In ground-nesting species, producing eggs that are visually undetectable by predators is the best camouflage strategy. However, the condition-dependence of eggshell pigmentation, and the pigments role in oxidative stress, may constrain females to trade-off between their antioxidant capacity and maximising the camouflage of their eggs when they deposit eggshell pigments. Developmental stress is one factor that influences female antioxidant capacity, and could lead to variations in eggshell pigmentation that might have crucial consequences on individual fitness if egg crypsis is compromised especially under stressful conditions. We investigated the interaction between developmental and breeding conditions with respect to eggshell pigmentation in Japanese quail. We studied 30 females that bred under both control and stressful conditions, and were exposed to pre- and/or post-natal stress, or neither. Pre- and post-natal stress independently influenced eggshell pigmentation strategies under stressful breeding conditions. Under stressful reproduction, eggshell protoporphyrin concentration and maculation were affected by pre-natal stress, whereas eggshell reflectance and biliverdin concentration were influenced by post-natal stress. These changes may reflect potential adaptive strategies shaped by developmental stress, but additional data on the benefit of egg crypsis in quail, combined with studies on the role of both pigments on chick survival, will help to clarify whether early life stress can enhance fitness through eggshell pigmentation when developmental and reproductive environments match.

• Klíčová slova
• Breeding conditions, Developmental history, Early-life stress, Eggshell pigmentation, Japanese quail1,
• MeSH
• chov MeSH
• Coturnix fyziologie   MeSH
• fyziologický stres * MeSH
• novorozená zvířata MeSH
• pigmentace fyziologie   MeSH
• rozmnožování fyziologie   MeSH
• tělesná hmotnost MeSH
• vaječná skořápka fyziologie   MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Alternative reproductive tactics (ARTs) are prevalent in nature, where smaller parasitic males typically have better sperm quality than larger territorial guard males. At present, it is unclear what is causing this phenomenon. Our objective was to gain insights into sperm form and function by examining flagellar beating patterns (beat frequency, wave amplitude, bend length, bend angle, wave velocity) and biomechanical sperm metrics (velocity, hydrodynamic power output, propulsive efficiency) of wild spawning Chinook salmon ARTs. Ovarian fluid and milt were collected to form a series of eight experimental blocks, each composed of ovarian fluid from a unique female and sperm from a unique pair of parasitic jack and guard hooknose males. Sperm from each ART were activated in river water and ovarian fluid. Flagellar parameters were evaluated from recordings using high-speed video microscopy and biomechanical metrics were quantified. We show that ART has an impact on flagellar beating, where jacks had a higher bend length and bend angle than hooknoses. Activation media also impacted the pattern of flagellar parameters, such that beat frequency, wave velocity and bend angle declined, while wave amplitude of flagella increased when ovarian fluid was incorporated into activation media. Furthermore, we found that sperm from jacks swam faster than those from hooknoses and required less hydrodynamic power output to propel themselves in river water and ovarian fluid. Jack sperm were also more efficient at swimming than hooknose sperm, and propulsive efficiency increased when cells were activated in ovarian fluid. The results demonstrate that sperm biomechanics may be driving divergence in competitive reproductive success between ARTs.

• Klíčová slova
• Cryptic female choice, Oncorhynchus tshawytscha, Reproductive strategy, Salmon, Spawning, Sperm competition,
• MeSH
• bičík spermie fyziologie   MeSH
• biomechanika MeSH
• losos fyziologie   MeSH
• motilita spermií * MeSH
• ovarium fyziologie   MeSH
• rozmnožování fyziologie   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH
• Geografické názvy
• Ontario MeSH

Factors which indicate lower life expectancy also induce switching to a faster life strategy, that is, a higher investment in current reproduction at the expense of future reproduction and body maintenance. We tested a hypothesis according to which impairment of individual health serves as a signal for switching to a faster life strategy using online-gathered data from 32,911 subjects. Worse health was associated with lower age at menarche and earlier initiation of sexual life in women and higher sexual desire and earlier reproduction in both sexes. Individuals with worse health also exhibited lower sexual activity, lower number of sexual partners, and lower total number of children. These results suggest that impaired health shifts individuals towards a faster life strategy but also has a negative (physiological) effect on behaviours related to sexual life. Signs of a faster life strategy were also found in Rh-negative men in good health, indicating that even just genetic predisposition to worse health could serve as a signal for switching to a faster life strategy. We suggest that improved public health in developed countries and the resulting shift to a slower life strategy could be the ultimate cause of the phenomenon of demographic transition.

• MeSH
• dospělí MeSH
• libido fyziologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• menarche fyziologie   MeSH
• mladý dospělý MeSH
• rozmnožování fyziologie   MeSH
• sexuální chování fyziologie   MeSH
• věkové faktory MeSH
• zdravotní stav MeSH
• zvláštnosti životní historie MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The scarcity of parthenogenetic vertebrates is often attributed to their 'inferior' mode of clonal reproduction, which restricts them to self-reproduce their own genotype lineage and leaves little evolutionary potential with regard to speciation and evolution of sexual reproduction. Here, we show that for some taxa, such uniformity does not hold. Using hybridogenetic water frogs (Pelophylax esculentus) as a model system, we demonstrate that triploid hybrid males from two geographic regions exhibit very different reproductive modes. With an integrative data set combining field studies, crossing experiments, flow cytometry and microsatellite analyses, we found that triploid hybrids from Central Europe are rare, occur in male sex only and form diploid gametes of a single clonal lineage. In contrast, triploid hybrids from north-western Europe are widespread, occur in both sexes and produce recombined haploid gametes. These differences translate into contrasting reproductive roles between regions. In Central Europe, triploid hybrid males sexually parasitize diploid hybrids and just perpetuate their own genotype--which is the usual pattern in parthenogens. In north-western Europe, on the other hand, the triploid males are gamete donors for diploid hybrids, thereby stabilizing the mixed 2n-3n hybrid populations. By demonstrating these contrasting roles in male reproduction, we draw attention to a new significant evolutionary potential for animals with nonsexual reproduction, namely reproductive plasticity.

• Klíčová slova
• Rana, all-hybrid population, asexual reproduction, gamete production, hemiclone, hybridization, hybridogenesis, polyploidy, sexual parasite, sperm-dependent parthenogenesis,
• MeSH
• genetická variace MeSH
• mikrosatelitní repetice MeSH
• partenogeneze MeSH
• poměr pohlaví MeSH
• populační genetika * MeSH
• Ranidae genetika   MeSH
• rozmnožování genetika   MeSH
• triploidie * MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH
• Evropa MeSH
• Slovenská republika MeSH

Ecological preferences, partner compatibility, or partner availability are known to be important factors shaping obligate and intimate lichen symbioses. We considered a complex of Cladonia species, traditionally differentiated by the extent of sexual reproduction and the type of vegetative propagules, to assess if the reproductive and dispersal strategies affect mycobiont-photobiont association patterns. In total 85 lichen thalli from 72 European localities were studied, two genetic markers for both Cladonia mycobionts and Asterochloris photobionts were analyzed. Variance partitioning analysis by multiple regression on distance matrices was performed to describe and partition variance in photobiont genetic diversity. Asexually reproducing Cladonia in our study were found to be strongly specific to their photobionts, associating with only two closely related Asterochloris species. In contrast, sexually reproducing lichens associated with seven unrelated Asterochloris lineages, thus being photobiont generalists. The reproductive mode had the largest explanatory power, explaining 44% of the total photobiont variability. Reproductive and dispersal strategies are the key factors shaping photobiont diversity in this group of Cladonia lichens. A strict photobiont specialisation observed in two studied species may steer both evolutionary flexibility and responses to ecological changes of these organisms, and considerably limit their distribution ranges.

• Klíčová slova
• Asterochloris, Distribution, Phylogeny, Specialist pattern, Specificity, Symbiosis,
• MeSH
• Ascomycota klasifikace   MeSH
• biodiverzita * MeSH
• Chlorophyta klasifikace   genetika   MeSH
• fylogeneze MeSH
• lišejníky klasifikace   genetika   MeSH
• rozmnožování MeSH
• šíření semen fyziologie   MeSH
• symbióza * MeSH
• zeměpis MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Evropa MeSH

The combination of a flow cytometric seed screen and genotyping of each single seed offers a cost-effective approach to detecting complex reproductive pathways in flowering plants. Reproduction may be seen as one of the driving forces of evolution. Flow cytometric seed screen and genotyping of parents and progeny are commonly employed techniques to discern various modes of reproduction in flowering plants. Nevertheless, both methods possess limitations constraining their individual capacity to investigate reproductive modes thoroughly. We implemented both methods in a novel manner to analyse reproduction pathways using a carefully selected material of parental individuals and their seed progeny. The significant advantage of this approach lies in its ability to apply both methods to a single seed. The introduced methodology provides valuable insights into discerning the levels of apomixis, sexuality, and selfing in complex Rubus taxa. The results may be explained by the occurrence of automixis in Rubus, which warrants further investigation. The approach showcased its effectiveness in a different apomictic system, specifically in Taraxacum. Our study presents a comprehensive methodological approach for determining the mode of reproduction where flow cytometry loses its potential. It provides a reliable and cost-effective method with significant potential in biosystematics, population genetics, and crop breeding.

• Klíčová slova
• Rubus, Taraxacum, Apomixis, Automixis, FCSS, SSR-seq,
• MeSH
• apomixie * genetika   fyziologie   MeSH
• genotyp MeSH
• průtoková cytometrie * MeSH
• rozmnožování MeSH
• semena rostlinná * genetika   fyziologie   MeSH
• Taraxacum fyziologie   genetika   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Microplastics (MPs) are widespread contaminants in aquatic ecosystems and pose significant threats to both organisms and the environment. Their small size, high surface area, and capacity to adsorb toxic chemicals allow MPs to infiltrate food webs, affecting organisms across trophic levels. This review explores the intricate mechanisms by which MPs induce reproductive and endocrine toxicity, focusing on their physical and chemical properties, bioaccumulation dynamics, and associated molecular pathways. MPs interfere with hormonal homeostasis, oxidative stress responses, and apoptotic pathways, leading to disruptions in the hypothalamic-pituitary-gonadal axis, impaired steroidogenesis, and gonadal dysfunction. These effects manifest as reduced fertility, altered gametogenesis, and multigenerational reproductive impairments across diverse aquatic taxa. Furthermore, MPs serve as carriers for endocrine-disrupting chemicals, compounding their adverse effects on organisms and aquatic biodiversity. Through a synthesis of recent research, this review identifies key signaling pathways, including MAPK, PI3K-AKT, mTOR, NF-κB, PPAR and NLRP3 inflammasome, that may play a role in MP-induced reproductive toxicity. The findings underscore the urgent need for advanced mitigation strategies, regulatory frameworks, and further research to combat the ecological consequences of MP pollution. Prioritizing targeted interventions is essential to safeguard aquatic biodiversity and ensure ecosystem resilience against the pervasive threat of MPs.

• Klíčová slova
• Endocrine system, Microplastics, Oxidative stress, Reproduction,
• MeSH
• chemické látky znečišťující vodu * toxicita   MeSH
• endokrinní disruptory toxicita   MeSH
• mikroplasty * toxicita   MeSH
• rozmnožování * účinky léků   MeSH
• vodní organismy * účinky léků   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• chemické látky znečišťující vodu * MeSH
• endokrinní disruptory MeSH
• mikroplasty * MeSH

OBJECTIVE: Sexual arousal by dominance and submissiveness was long considered a mental disorder. The origin of this sexual preference has not been clearly explained. This study scrutinizes the hypothesis that sexual arousal by hierarchical disparity is a manifestation of mating strategy by comparing number of offspring and self-reported attractiveness of the study participants. METHODS: Our data were obtained from the general population via e-mail questionnaire (n=673, age 25-34 years and 35-44 years). RESULTS: Sexually dominant men aged 35-44 years had more biological male children. Both the sexually dominant men aged 35-44 years and sexually submissive women aged 35-44 years perceived themselves as being more attractive. THE MAIN FINDINGS: Here we show that sexual arousal by dominance and submissiveness confers an increased capacity to pass on genes in the general population. CONCLUSION: We suggest that sexual arousal by dominance is likely to be the means by which the mating strategy is accomplished. Sexual arousal by dominance and submissiveness is a manifestation of mating strategy because such a behaviour results in an increased reproductive success and thus may lead to the preferential selection of individuals who prefer sexual arousal by hierarchical disparity. This fact explains why the high number of people is excited by sexual fantasies and activities connected to hierarchical disparity. This finding might open up novel insights into some reproductive medicine issues, as well as into such field as partnership therapy and partner violence.

• MeSH
• dominance a subordinace * MeSH
• dospělí MeSH
• emoce fyziologie   MeSH
• libido fyziologie   MeSH
• lidé MeSH
• rozmnožování fyziologie   MeSH
• sebepojetí * MeSH
• sexuální chování fyziologie   MeSH
• sexuální faktory MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Biological invasions in remote areas that experience low human activity provide unique opportunities to elucidate processes responsible for invasion success. Here we study the most widespread invasive plant species across the isolated islands of the Southern Ocean, the annual bluegrass, Poa annua. To analyse geographical variation in genome size, genetic diversity and reproductive strategies, we sampled all major sub-Antarctic archipelagos in this region and generated microsatellite data for 470 individual plants representing 31 populations. We also estimated genome sizes for a subset of individuals using flow cytometry. Occasional events of island colonization are expected to result in high genetic structure among islands, overall low genetic diversity and increased self-fertilization, but we show that this is not the case for P. annua. Microsatellite data indicated low population genetic structure and lack of isolation by distance among the sub-Antarctic archipelagos we sampled, but high population structure within each archipelago. We identified high levels of genetic diversity, low clonality and low selfing rates in sub-Antarctic P. annua populations (contrary to rates typical of continental populations). In turn, estimates of selfing declined in populations as genetic diversity increased. Additionally, we found that most P. annua individuals are probably tetraploid and that only slight variation exists in genome size across the Southern Ocean. Our findings suggest multiple independent introductions of P. annua into the sub-Antarctic, which promoted the establishment of genetically diverse populations. Despite multiple introductions, the adoption of convergent reproductive strategies (outcrossing) happened independently in each major archipelago. The combination of polyploidy and a mixed reproductive strategy probably benefited P. annua in the Southern Ocean by increasing genetic diversity and its ability to cope with the novel environmental conditions.

• Klíčová slova
• Poa annua, biological invasions, breeding systems, clonality, genetic variation, islands, polyploidy, population genetics, self-fertilization, sub-Antarctic,
• MeSH
• genetická variace * genetika   MeSH
• lidé MeSH
• mikrosatelitní repetice genetika   MeSH
• oceány a moře MeSH
• polyploidie * MeSH
• rozmnožování MeSH
• zavlečené druhy MeSH
• zeměpis MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• oceány a moře MeSH

Reproductive strategies play a major role in plant speciation. Notably, transitions from outcrossing to selfing may lead to relaxed sexual selection and parental conflict. Shifts in mating systems can affect maternal and paternal interests, and thus parent-specific influence on endosperm development, leading to reproductive isolation: if selfing and outcrossing species hybridize, the resulting seeds may not be viable due to endosperm failure. Nevertheless, it remains unclear how the switch in mating systems can impact reproductive isolation between recently diverged lineages, that is, during the process of speciation. We investigated this question using Arabidopsis lyrata, which recently transitioned to selfing (10,000 years ago) in certain North American populations, where European populations remain outcrossing. We performed reciprocal crosses between selfers and outcrossers, and measured seed viability and endosperm development. We show that parental genomes in the hybrid seed negatively interact, as predicted by parental conflict. This leads to extensive hybrid seed lethality associated with endosperm cellularization disturbance. Our results suggest that this is primarily driven by divergent evolution of the paternal genome between selfers and outcrossers. In addition, we observed other hybrid seed defects, suggesting that sex-specific interests are not the only processes contributing to postzygotic reproductive isolation.

• Klíčová slova
• Arabidopsis lyrata, Hybrid seed lethality, endosperm balance number, gray zone of speciation, mating system divergence,
• MeSH
• Arabidopsis genetika   fyziologie   MeSH
• endosperm genetika   MeSH
• fenotyp MeSH
• hybridizace genetická * MeSH
• křížení genetické MeSH
• reprodukční izolace * MeSH
• rozmnožování MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH