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Finding interventions to break the trade-off between reproduction and lifespan can provide insight into physiological limitations of animals. Effects of dietary protein quality on the trade-off are currently unclear, but clarity could lead to better designed diets that match animal needs. Dietary amino acid blends matching yolk proteins support reproduction and extend lifespan in fruit flies. To test if this is conserved across species, we matched dietary amino acids to vitellogenin to test reproduction and lifespan in adult females of the lubber grasshopper. Specifically, we compared varying degrees of protein quality by manipulating dietary essential amino acids. We identified a high-quality protein diet (amino acids matched to vitellogenin, or reproductive needs) that increased reproduction and matched lifespan in comparison to diets that differed only in the ratios of essential amino acids (i.e., were isocaloric and isonitrogenous). All these diets had longer lifespan but lower reproductive output than fully fed controls. In a separate experiment, full reproduction was possible on the high-quality artificial diet when offered at a 78% higher protein quantity and with a larger lettuce supplement (~ 17% of ad libitum). Additionally, we observed that as dietary protein quality was decreased (i.e., diets were less matched to vitellogenin), reproduction was reduced, and lifespan was extended in the more extreme scenarios. Taken together, these results indicate that the balance of dietary essential amino acids plays an important role in the lifespan and reproduction trade-off, while more work needs to be conducted to find the optimal diet mix for this species. [ABSTRACT FROM AUTHOR]

Finding interventions to break the trade-off between reproduction and lifespan can provide insight into physiological limitations of animals. Effects of dietary protein quality on the trade-off are currently unclear, but clarity could lead to better designed diets that match animal needs. Dietary amino acid blends matching yolk proteins support reproduction and extend lifespan in fruit flies. To test if this is conserved across species, we matched dietary amino acids to vitellogenin to test reproduction and lifespan in adult females of the lubber grasshopper. Specifically, we compared varying degrees of protein quality by manipulating dietary essential amino acids. We identified a high-quality protein diet (amino acids matched to vitellogenin, or reproductive needs) that increased reproduction and matched lifespan in comparison to diets that differed only in the ratios of essential amino acids (i.e., were isocaloric and isonitrogenous). All these diets had longer lifespan but lower reproductive output than fully fed controls. In a separate experiment, full reproduction was possible on the high-quality artificial diet when offered at a 78% higher protein quantity and with a larger lettuce supplement (~ 17% of ad libitum). Additionally, we observed that as dietary protein quality was decreased (i.e., diets were less matched to vitellogenin), reproduction was reduced, and lifespan was extended in the more extreme scenarios. Taken together, these results indicate that the balance of dietary essential amino acids plays an important role in the lifespan and reproduction trade-off, while more work needs to be conducted to find the optimal diet mix for this species. [ABSTRACT FROM AUTHOR]

Life history theory suggests that females should allocate greater resources to immune function than males to increase their lifetime fitness. Although higher immune responses in adult females compared to males have been reported across various insect species, sexual differences in immunity during juvenile stages have been less explored. We investigated sexual differences in haemocyte density and phenoloxidase (PO) activiy in two species of rhinoceros beetles, Trypoxylus dichotomus (Linnaeus) (Coleoptera: Scarabaeidae) and Oryctes rhinoceros (Linnaeus) (Coleoptera: Scarabaeidae), during their larval stages. We found that male T. dichotomus larvae consistently displayed lower haemocyte densities than females, and this sexual difference persisted until adulthood. The sexual difference in immunity across life stages may be associated with sex-specific resource allocation patterns throughout lifetime. However, the less sexually-dimorphic species, O. rhinoceros, did not exhibit sexual differences in haemocyte densities during immature stages. PO activities did not exhibit sexual differences in larvae of either species. Additionally, we observed an increase in haemocyte densities with larval developmental stages in both species. However, while T. dichotomus exhibited lower PO activities in later stages, PO activities in O. rhinoceros did not largely change throughout development. Path analysis revealed that the ontogenetic changes in constitutive immune parameters were primarily driven by direct effects of body size rather than age. The species- and parameter-specific ontogenetic trends in immunity could be associated with allocation to other life history traits or tradeoffs among immunity parameters. [ABSTRACT FROM AUTHOR]

Phenology is a major component of animals’ breeding, as they need to adjust their breeding timing to match optimal environmental conditions. While the effects of shifting phenology are well-studied on populations, few studies emphasise its ecological causes and consequences at the inter-individual level. Using a 20-year monitoring of more than 2500 breeding events from ~ 500 breeding little penguins (Eudyptula minor), a very asynchronously breeding seabird, we investigated the consequences of late breeding on present and next breeding events. We found that individuals breeding later had reduced breeding success, lighter chicks at fledging, lower probability of laying a second clutch, and decreased parents’ post-breeding body condition. Importantly, we found important cycling effects where delayed breeding during a given year led to significantly later laying date, lower breeding probability and lower breeding success when they breed during the next season, suggesting potential carry-over effects from one season to the next. To further understand the causes of such variability in phenology while earlier breeding is associated with better individual fitness, we aimed to assess intrinsic differences amongst individuals. We showed that the heterogeneity in breeding timing was partly fixed, the laying date being a significantly repeatable behaviour (17%), asking for more studies on heritability or early-development effects. This extensive study highlights the combined roles of carry-over effects and intrinsic differences on individual phenology, with important implications on breeding capacity through life. [ABSTRACT FROM AUTHOR]

Isolation and limited migration among populations and differences in the environments they inhabit set up conditions for population differentiation of life‐history traits, even across a regional spatial scale, such as a statewide landscape of lakes and reservoirs. Our objective was to understand how largemouth bass (Micropterus nigricans) life histories differ across a regional spatial scale (Ohio, USA) and whether environmental differences are influencing this variation. To address this, we (1) described spatial variation in largemouth bass life‐history traits, with a specific interest in potential correlations between early‐life growth and later‐life traits and (2) tested whether life‐history traits can be predicted by reservoir characteristics. We found two groups of correlated population traits: the inverse relationship of early‐life growth rate with population density and asymptotic length and the positive relationship between adult size and asymptotic length. Early‐life growth had a positive relationship (and population density and asymptotic length had a negative relationship) with littoral habitat availability and other environmental conditions expected to enhance early growth. Despite the strong influence of reservoir characteristics on life‐history traits in our analysis, the most plausible model could not give precise predictions of these life‐history traits, suggesting that the availability of data on other aspects of the populations and environments may improve our ability to understand life‐history differences. Overall, our results suggest that, even among recently separated populations, we should expect differences in growth patterns and that we cannot understand drivers of these differences without considering possible correlations in growth patterns across the lifespan. [ABSTRACT FROM AUTHOR]

Non-lethal injury in animals is both common and costly. The cost of regenerating autotomized limbs may leave less energy available for processes such as reproduction and growth, leading to trade-offs. Such trade-offs are context-dependent, and an individual's energy allocation strategies may vary widely based on its condition and the environment. However, many traditional bioenergetics models have relied on fixed energy allocation rules, such as the -rule of dynamic energy budget theory, which assumes a fixed proportion (κ) of assimilated energy is always allocated to growth and maintenance. To determine whether incorporating optimality approaches into bioenergetics models improves the ability to predict energy allocation, we developed a dynamic state variable model that identifies optimal limb regeneration strategies in a model system, the Asian shore crab Hemigrapsus sanguineus. Our model predictions align with known patterns for this species, including increased regeneration effort with injury severity, a shift from reproduction to growth as consumption amount increases, and an increase in regeneration effort as regeneration progresses. Lastly, Monte Carlo simulations of individuals from a previous experiment demonstrate that flexible energy allocation successfully predicts reproductive effort, suggesting that this approach may improve the accuracy of bioenergetics modeling. [ABSTRACT FROM AUTHOR]

In North America, most ungulate species exhibit life‐history traits typical of long‐lived, iteroparous species wherein young males tend to prioritize essential life functions including body growth and maintenance that constrains allocation of resources to horn, antler, and pronghorn growth. As a result, males of most ungulate species require several years of growth before reaching asymptotic body size and thereafter, peak weapon size is attained. Unique among ungulate species in North America, pronghorn possess a suite of life‐history traits resulting in a precocious (i.e., unusually early development) pace of life relative to other North American ungulates. We tested the hypothesis that the fast pace of life of pronghorn extends to precocious development of large horns, and evaluated how horn size was affected by environmental conditions during the year they were grown and the potential for cohort effects associated with environmental signatures during the year of birth. We evaluated the influence of age and the environment on horn size of pronghorn using data collected from 1,789 male pronghorn harvested from 2019 to 2022 in Wyoming, USA. Pronghorn attained 95% of their peak horn size by 3.5 years old. Climatic conditions influenced horn growth through cohort effects and year of growth pathways. Snow depth during the year of birth positively influenced horn size, whereas the effects of environmental conditions during the year of horn growth were dependent on age. For young animals, snow depth and moderate drought positively influenced horn size during the year of horn growth, but the effect was negligible for prime aged and old animals. The precocious nature of pronghorn extended to their horn growth characteristics, resulting in early attainment of a large proportion of their peak horn size. The unique ecology of pronghorn and rapid attainment of size early in life can allow for greater flexibility to balance hunter opportunity and production of large‐horned males for pronghorn as compared with other ungulates. [ABSTRACT FROM AUTHOR]

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Annuality and perenniality represent two different life‐history strategies in plants, and an analysis of genomic differentiation between closely related species of different life histories bears the potential to identify the underlying targets of selection. Additionally, understanding the interactions between patterns of recombination and signatures of natural selection is a central aim in evolutionary biology, because patterns of recombination shape the evolution of genomes by affecting the efficacy of selection. Here, our aim was to characterise the landscape of genomic differentiation between weedy annual rye (Secale cereale L.) and wild perennial rye (Secale strictum C. Presl), and explore the extent to which signatures of selection are influenced by recombination rate variation. We used population‐level sequence data of annual and perennial rye to analyse population structure and their demographic history. Based on our analyses, annual and perennial rye diverged approximately 26,500 years ago (ya) from an ancestral population size of ~85,000 individuals. We analysed patterns of genetic diversity and genetic differentiation, and found highly differentiated regions located in low‐recombination regions, indicative of linked selection. Although all highly differentiated regions, as revealed by FST‐outlier scans, were located in low‐recombining regions, not all chromosomes showed this tendency. We therefore performed a gene ontology enrichment analysis, which showed that highly differentiated regions comprise genes involved in photosynthesis. This enrichment was confirmed when FST outlier scans were performed separately in low‐ and intermediate‐recombining regions, but not in high‐recombining regions, suggesting that local recombination rate variation in rye affects outlier scans. Cultivated rye is an annual crop, but the introduction of perenniality may be advantageous in regions with poor soil quality or under low‐input farming. Although the resolution of our analysis is limited to a broad‐scale, knowledge about the evolutionary divergence between annual and perennial rye might support breeding efforts towards perennial rye cultivation. [ABSTRACT FROM AUTHOR]

Hox genes are transcriptional regulators that elicit cell positional identity along the anterior–posterior region of the body plan across different lineages of Metazoan. Comparison of Hox gene expression across distinct species reveals their evolutionary conservation; however, their gains and losses in different lineages can correlate with body plan modifications and morphological novelty. We compare the expression of 11 Hox genes found within Streblospio benedicti, a marine annelid that produces two types of offspring with distinct developmental and morphological features. For these two distinct larval types, we compare Hox gene expression through ontogeny using hybridization chain reaction (HCR) probes for in situ hybridization and RNA-seq data. We find that Hox gene expression patterning for both types is typically similar at equivalent developmental stages. However, some Hox genes have spatial or temporal differences between the larval types that are associated with morphological and life-history differences. This is the first comparison of developmental divergence in Hox gene expression within a single species and these changes reveal how body plan differences may arise in larval evolution. [ABSTRACT FROM AUTHOR]

The costs of reproductive conflict can shape the evolution of life-histories in animal societies. These costs may change as individuals age and grow, and with within-group competition. Social costs of reproductive conflict have been invoked to explain why females might gain from delaying maturity or ceasing reproduction midway through life, but not in males. Here, we analyse more than 20 years of data to understand how individual male banded mongooses adjust their reproductive activity in response to the costs of reproductive conflict. In banded mongoose groups, multiple female breeders enter oestrus synchronously that are each guarded by a single male that aggressively wards-off rivals. The heaviest males in the group gained the greatest share of paternity. Those lighter males that are reproductively active paid disproportionate survival costs, and by engaging in reproductive activity early had lower lifetime reproductive success. Our results suggest that reproductive inactivity early in life is adaptive, as males recoup any lost fitness by first growing before engaging in less costly and more profitable reproductive activity later in life. These results suggest that resource holding potential of males and the intensity of reproductive conflict interact to shape lifetime schedules of reproductive behaviour. [ABSTRACT FROM AUTHOR]

Reproductive activity is costly in terms of future reproduction and survival. Oxidative stress has been identified as a likely mechanism underlying this cost of reproduction. However, empirical studies have yielded the paradoxical observation that breeders often sustain lower levels of oxidative damage than non-breeders. The oxidative shielding hypothesis attempts to explain such data, and posits that breeders pre-emptively reduce levels of oxidative damage in order to protect their germ cells, and any resultant offspring, from harm caused by exposure to oxidative damage. While there is some empirical evidence of oxidative shielding in females, there have been no explicit tests of this hypothesis in males, despite evidence of the oxidative costs to the male reproductive effort and the vulnerability of sperm cells to oxidative damage. In this study, we assess lipid oxidative damage (malondialdehyde, MDA) in the ejaculates of reproducing and non-reproducing wild banded mongooses. We found that, among breeding males, ejaculate MDA levels were lower during mate competition compared to 2 months later, when individuals were not mating, which is consistent with the oxidative shielding hypothesis, and similar to findings in females. However, ejaculate MDA levels did not differ significantly between breeding and non-breeding individuals at the time of mating, contrary to expectation. The finding that ejaculate MDA was not higher in non-breeders may reflect individual differences in quality and hence oxidative stress. In particular, breeders were significantly older than non-breeders, which may obscure differences in oxidative damage due to reproductive investment. Further research is needed to establish the causal relationship between reproductive investment and oxidative damage in ejaculates, and the consequences for offspring development in banded mongooses and other species. [ABSTRACT FROM AUTHOR]

Climate change is altering temperature means and variation, and both need to be considered in predictions underpinning conservation. However, there is no consensus in the literature regarding the effects of temperature fluctuations on biological functions. Fluctuations may affect biological responses because of inequalities from non‐linear responses, endocrine regulation or exposure to damaging temperatures. Here we establish the current state of knowledge of how temperature fluctuations impact biological responses within individuals and populations compared to constant temperatures with the same mean. We conducted a meta‐analysis of 143 studies on ectothermic animals (1492 effect sizes, 118 species). In this study, 89% of effect sizes were derived from diel cycles, but there were no significant differences between diel cycles and shorter (<8 h) or longer (>48 h) cycles in their effect on biological responses. We show that temperature fluctuations have little effect overall on trait mean and variance. Nonetheless, temperature fluctuations can be stressful: fluctuations increased 'gene expression' in aquatic animals, which was driven mainly by increased hsp70. Fluctuating temperatures also decreased longevity, and increased amplitudes had negative effects on population responses in aquatic organisms. We conclude that mean temperatures and extreme events such as heat waves are important to consider, but regular (particularly diel) temperature fluctuations are less so. [ABSTRACT FROM AUTHOR]

Males and females often differ in ecology, behaviour and lifestyle, and these differences are expected to lead to sex differences in parasite susceptibility. However, neither the sex differences in parasite prevalence, nor their ecological and evolutionary drivers have been investigated across a broad range of taxa using phylogenetically corrected analyses. Using the most extensive dataset yet that includes 755 prevalence estimates from 151 wild bird species in a meta-analytic framework, here we compare sex differences in blood and gastrointestinal parasites. We show that despite sex differences in parasite infection being frequently reported in the literature, only Haemoproteus infections were more prevalent in females than in males. Notably, only seasonality was strongly associated with the sex-specific parasite prevalence of both Leucocytozoon and Haemoproteus, where birds showed greater female bias in prevalence during breeding periods compared to the non-breeding period. No other ecological or sexual selection variables were associated with sex-specific prevalence of parasite prevalence. We suggest that much of the variation in sex-biased prevalence could be idiosyncratic, and driven by local ecology and behavioural differences of the parasite and the host. Therefore, breeding ecology and sexual selection may only have a modest influence on sex-different parasite prevalence across wild birds. [ABSTRACT FROM AUTHOR]

Linking reproductive fitness with adaptive traits at the genomic level can shed light on the mechanisms that produce and maintain sex‐specific selection. Here, we construct a multigenerational pedigree to investigate sex‐specific selection on a maturation gene, vgll3, in a wild Atlantic salmon population. The vgll3 locus is responsible for ~40% of the variation in maturation (sea age at first reproduction). Genetic parentage analysis was conducted on 18,265 juveniles (parr) and 685 adults collected at the same spawning ground over eight consecutive years. A high proportion of females (26%) were iteroparous and reproduced two to four times in their lifetime. A smaller proportion of males (9%) spawned at least twice in their lifetime. Sex‐specific patterns of reproductive fitness were related to vgll3 genotype. Females showed a pattern of overdominance where vgll3*EL genotypes had three‐fold more total offspring than homozygous females. In contrast, males demonstrated that late‐maturing vgll3*LL individuals had two‐fold more offspring than either vgll3*EE or vgll3*EL males. Taken together, these data suggest that balancing selection in females contributes to the maintenance of variation at this locus via increased fitness of iteroparous vgll3*EL females. This study demonstrates the utility of multigenerational pedigrees for uncovering complex patterns of reproduction, sex‐specific selection and the maintenance of genetic variation. [ABSTRACT FROM AUTHOR]

Climate change has appeared as a major issue in recent years, and its impacts are seen multi-dimensionally. The local people are the key eyewitnesses of climate change, although the discourse is disciplinary, geographic, and gender biased. In this context, this paper documents the perceptions and narratives of the Tamang, an Indigenous people, who live on the outskirts of the Kathmandu Valley. This is an ethnographic study and applied quantitative and qualitative data. The data of the study were gathered using triangulation methods, i.e., household questionnaire survey (HQS), key informant interview (KII), and focus group discussion (FGD). A total of 94 HQS, nine KII, and three FGD were carried out in 2018 in three sample sites in the outskirts of the valley. The station-based observed climatic data from 1969 to 2022 were collected from the Department of Hydrology and Meteorology. The observed data shows increasing annual rainfall and temperature in Kathmandu; however, the rate of temperature increase is much larger. Seasonal precipitation shows decreasing rainfall in post-monsoon, which enhances the winter drought. The Tamang are the key eyewitness of the changes in climate and this knowledge is inbuilt with their memories which are closely bound to the place. Hence, the life history of elderly people can be an appropriate way of understanding the micro-climatic changes in the local context, which largely failed or ignored to document in scientific or macro-level assessments. [ABSTRACT FROM AUTHOR]

Individuals must reproduce to survive and thrive from generation to generation. In fish, the fecundity of individuals and estimates of total reproductive output are critical for evaluating reproductive success and understanding population dynamics. Estimating fecundity is an onerous task; therefore, many populations lack contemporary estimates of fecundity and size‐fecundity relationships. However, reproductive dynamics are not static in time; therefore, it is important to develop contemporary fecundity estimates to better inform conservation and management action. To highlight the importance of contemporary fecundity estimates, we examined the fecundity of southern Gulf of St. Lawrence (sGSL) spring and fall spawning Atlantic herring in 2022, developed size‐fecundity models, and compared these to historical fecundity estimates and models. Our results suggest that the average fecundity of sGSL spring and fall herring has undergone a substantial temporal decline of approximately 47% and 58%, respectively, since the 1970s and 1980s. The size‐fecundity relationships for fall spawning herring have shifted, with fish of a given size exhibiting lower fecundity in 2022 compared to the 1970s. Alternatively, the size‐fecundity relationships for spring spawning herring have remained relatively static. Furthermore, simulations highlighted a substantial reduction in potential reproductive output in 2022 compared to 1970 of approximately 32% and 68% for spring and fall spawners, respectively, based on a fixed number of mature females, which may have negative implications for stock rebuilding. Overall, our study provides support for periodic estimates of fecundity in fish populations to better understand temporal changes in reproductive and population dynamics. [ABSTRACT FROM AUTHOR]

Species exploiting seasonal environments must alter timings of key life‐history events in response to large‐scale climatic changes in order to maintain trophic synchrony with required resources. Yet, substantial among‐species variation in long‐term phenological changes has been observed. Advancing from simply describing such variation towards predicting future phenological responses requires studies that rigorously quantify and explain variation in the direction and magnitude of changing timings across diverse species in relation to key ecological and life‐history variables. Accordingly, we fitted multi‐quantile regressions to 59 years of multi‐species data on spring and autumn bird migration timings through northern Scotland. We demonstrate substantial variation in changes in timings among 72 species, and tested whether such variation can be explained by species ecology, life‐history and changes in local abundance. Consistent with predictions, species that advanced their migration timing in one or both seasons had more seasonally restricted diet types, fewer suitable breeding habitat types, shorter generation lengths and capability to produce multiple offspring broods per year. In contrast, species with less seasonally restricted diet types and that produce single annual offspring broods, showed no change. Meanwhile, contrary to prediction, long‐distance and short‐distance migrants advanced migration timings similarly. Changes in migration timing also varied with changes in local migratory abundance, such that species with increasing seasonal abundance apparently altered their migration timing, whilst species with decreasing abundance did not. Such patterns broadly concur with expectation given adaptive changes in migration timing. However, we demonstrate that similar patterns can be generated by numerical sampling given changing local abundances. Any apparent phenology‐abundance relationships should, therefore, be carefully validated and interpreted. Overall, our results show that migrant bird species with differing ecologies and life‐histories showed systematically differing phenological changes over six decades contextualised by large‐scale environmental changes, potentially facilitating future predictions and altering temporal dynamics of seasonal species co‐occurrences. [ABSTRACT FROM AUTHOR]

Black bullhead Ameiurus melas is a widespread invasive fish in Europe and is considered an ecological and economic threat. Yet, sporadic data are available on its life-history traits. This study assessed the fecundity, growth, and body condition of black bullhead in three oxbows in Hungary. Samples were collected in the resting (October) and pre-spawning (April) periods. Considerable negative allometric growth was observed (b slope ranged between 1.64 and 1.67). The Fulton's condition factor was lower than any previously reported data (mean = 1.01; SD = 0.09). The mean male : female ratio of the three populations was 1.18:1. Mean absolute fecundity was 3,319 eggs (SD = 1521; range = 1,111-12,727), and mean relative fecundity was 78.8 eggs g-1 (SD = 21.8; range = 34.8-146.0). The mean oocyte diameter was 0.39 mm in autumn and 0.41 mm in spring. Oocyte size positively correlated with body length. The mean standard length at age was 76.5-81.00 mm at 1+, 126.23-134.35 at 2+, 153-154.5 mm at 3+, and 180-181 mm at 4+. Our results confirmed the phenotypic plasticity of black bullhead out of its native range. [ABSTRACT FROM AUTHOR]

Improve the knowledge base on the ecomorphological adaptation of teleost species to different environments, trying to reconstruct how habitat can shape sagittae, is essential for conservational purposes, evolutionary evaluations, and population dynamics studies. Here is provided a comparative study between sagittae features, growth rates and age composition of two Scorpaena porcus populations inhabiting the Mediterranean waters, one from the Strait of Messina (Central Mediterranean Sea) and one from the Split area (Adriatic Sea). Additionally, the stomach contents of the Messina specimens have also been analysed to provide some preliminary information on the diet of S. porcus. A total of ninety individuals, half from each area, have been obtained from two extremely different environments. Results showed an overall different morphology, shape, and morphometry of sagittae among the size classes of the two investigated populations. Samples from Messina were characterized by a most elliptical and slender shape, with a more regular serration of margins than those from Split, which exhibited a wider sagitta, with a most enhanced anti-rostrum and longer rostrum. Concerning diet, specimens from Messina showed a preference for Crustacea (especially Brachyura and Amphipoda) and Teleost species, showing some differences with literature data from other geographical areas (Split one included). Results have confirmed the reliability of sagittae to detect the interpopulation variability of S. porcus from different geographical areas, an essential tool for stock assessment, population studies and investigation on ecomorphological adaptation of teleost species to different habitats. [ABSTRACT FROM AUTHOR]

Mammalian life history strategies can be characterised by a few axes of variation, conforming a space where species are positioned based on the life history strategies favoured in the environment they exploit. Yet, we still lack global descriptions of the diversity of realised mammalian life history and how this diversity is shaped by the environment. We used six life history traits to build a life history space covering worldwide mammalian adaptation, and we explored how environmental realms (land, air, water) influence mammalian life history strategies. We demonstrate that realms are tightly linked to distinct life history strategies. Aquatic and aerial species predominantly adhere to slower life history strategies, while terrestrial species exhibit faster life histories. Highly encephalised terrestrial species are a notable exception to these patterns. Furthermore, we show that different mode of life may play a significant role in expanding the set of strategies exploitable in the terrestrial realm. Additionally, species transitioning between terrestrial and aquatic realms, such as seals, exhibit intermediate life history strategies. Our results provide compelling evidence of the link between environmental realms and the life history diversity of mammals, highlighting the importance of differences in mode of life to expand life history diversity. [ABSTRACT FROM AUTHOR]

The amniote eggshell is a fundamental aspect of the embryo life‐support system, protecting it from UV light, microbes and mechanical damage, while regulating gas exchange and providing calcium for growth. The thickness of eggshells is highly diverse across modern birds and influences multiple eggshell functions, yet the selective pressures driving eggshell thickness have not been clearly identified. Here, we use a global dataset of avian eggshell thickness indices for 4260 (> 41%) avian species to assess trends in eggshell thickness across the phylogeny, as these indices are strongly correlated with direct measures of eggshell thickness and are non‐destructive to the sample. We analysed the dataset within a phylogenetic framework to assess the relative importance of climatic and ecological explanations for variation in eggshell thickness indices. The distribution of avian eggshell thickness indices across species was found to be primarily driven by phylogenetic relatedness, in addition to evolutionary processes that do not match a Brownian model of evolution. Across modern birds, thicker eggshells were more prevalent in species (1) with precocial young, (2) which exhibit a scavenger‐based diet, (3) which primarily feed on vertebrates or plants (excluding nectivores, seed and fruit specialists) and (4) which breed in open habitats. Thicker eggshells found in species with precocial young probably enable higher rates of calcium removal for the more advanced embryo development. Excessive light transmission through the shell damages developing embryos, while too little light transmission can impede development. Eggs in shaded habitats experience low light exposure, and thus thinner shells are more prevalent in these environments potentially to increase light transmission through the shell. Overall, variation in eggshell thickness indices appears to be driven largely by phylogeny, with certain life‐history traits linked to embryo growth rate, calcium content of their food, and the need to mitigate excessive light transmission through the shell. [ABSTRACT FROM AUTHOR]

How the origin of novel behaviors can shape the evolutionary trajectory of organisms in response to environmental change remains poorly understood. Birds, especially those with big brains like parrots, are benchmarks for their behavioral innovation capacity in novel environments. Here, we assess whether and how the emergence of open areas in the Neotropics that started in the middle Miocene influenced the evolution of nesting behavior in parrots and how they triggered changes in other life‐history traits. To address these questions, we use a phylogenetic‐based analyses of trait evolution in the subfamily Arinae (Neotropical parrots), focusing on habitat, nesting behavior, morphology, and life‐history traits (clutch size, incubation period and fledging period). Evolutionary reconstructions show that transitions to excavating behavior mostly happened when species colonized open areas, providing evidence that this behavior originated in open environments. Evolutionary models suggest that the new open areas and the excavator nesting behavior exerted new selective pressures on morphology and life‐history traits, leading to evolutionary changes towards larger clutch sizes and shorter fledging periods in excavator parrots. Our study indicates that excavator nesting behavior in Neotropical parrots has likely played a key role in allowing them to exploit the ecological opportunities available in newly formed open biomes. [ABSTRACT FROM AUTHOR]

Life‐history theory predicts that reproductive investments are traded‐off against self‐maintenance. Telomeres, the protective caps on the ends of chromosomes, offer a promising avenue for assessing life‐history trade‐offs, as they shorten in response to stressors and are predictive of the remaining lifespan. In males, testosterone frequently mediates life‐history trade‐offs, in part, through its effects on sexual ornamentation, which is an important aspect of reproductive investment. However, studies of within‐individual associations between telomere dynamics and sexual ornamentation are limited in number and have produced mixed results. Furthermore, most such studies have been observational, making it difficult to discern the nature of any causal relationship. To address this, we used short‐acting testosterone implants in free‐living male superb fairy‐wrens (Malurus cyaneus) to stimulate the production of a sexual ornament: early moult into a costly blue breeding plumage. We found no evidence that elevated testosterone, and the consequent earlier moult into breeding plumage, accelerated telomere shortening. We therefore followed up with a systematic review and two meta‐analyses (28 studies, 54 effect sizes) exploring the associations between telomeres and (1) testosterone and (2) sexual ornamentation. In line with our experimental findings, neither meta‐analysis showed an overall correlation of testosterone or sexual ornamentation with telomere length or telomere dynamics. However, meta‐regression showed that experimental, compared to observational, studies reported greater evidence of trade‐offs. Our meta‐analyses highlight the need for further experimental studies to better understand potential responses of telomere length or telomere dynamics to testosterone or sexual ornamentation. [ABSTRACT FROM AUTHOR]

An animal's behaviour can influence many variables, such as its energy reserves, its risk of injury or mortality, and its rate of reproduction. To identify the optimal action in a given situation, these various effects can be compared in the common currency of reproductive value. While this idea has been widely used to study trade‐offs between pairs of variables, e.g. between energy gain versus survival, here we present a unified framework that makes explicit how these various trade‐offs fit together. This unification covers a wide range of biological phenomena, highlighting similarities in their logical structure and helping to identify knowledge gaps. To fill one such gap, we present a new model of foraging under the risk of predation and damage accumulation. We conclude by discussing the use and limitations of state‐dependent optimisation theory in predicting biological observations. [ABSTRACT FROM AUTHOR]

The transition between lytic and lysogenic life cycles is the most important feature of the life-history of temperate viruses. To explain this transition, an optimal life-history model is offered based a discrete-time formulation of phage/bacteria population dynamics that features infection of bacteria by Poisson sampling of virions from the environment. The time step is the viral latency period. In this model, density-dependent viral absorption onto the bacterial surface produces virus/bacteria coexistence and density dependence in bacterial growth is not needed. The formula for the transition between lytic and lysogenic phases is termed the 'fitness switch'. According to the model, the virus switches from lytic to lysogenic when its population grows faster as prophage than as virions produced by lysis of the infected cells, and conversely for the switch from lysogenic to lytic. A prophage that benefits the bacterium it infects automatically incurs lower fitness upon exiting the bacterial genome, resulting in its becoming locked into the bacterial genome in what is termed here as a 'prophage lock'. The fitness switch qualitatively predicts the ecogeographic rule that environmental enrichment leads to microbialization with a concomitant increase in lysogeny, fluctuating environmental conditions promote virus-mediated horizontal gene transfer, and prophage-containing bacteria can integrate into the microbiome of a eukaryotic host forming a functionally integrated tripartite holobiont. These predictions accord more with the 'Piggyback-the-Winner' hypothesis than with the 'Kill-the-Winner' hypothesis in virus ecology. [ABSTRACT FROM AUTHOR]

Simple Summary: The fall webworm, Hyphantria cunea (Drury) (Lepidoptera: Erebidae, Arctiidae), is a major invasive pest of China. Although it has spread from Dandong City (about 40° N) in Liaoning Province to Nanjing City (about 32° N) in Jiangsu Province and other areas, the effects of temperature changes associated with its geographical spread on its life-history traits and adult fecundity are still unknown. Thus, the current study investigated the effects of larval-rearing temperature on the developmental duration and body mass of larvae, body size, body mass, and energy reserves of pupae, as well as the body size and fecundity of adults. We found that higher larval-rearing temperatures shortened the larval developmental period and increased larval and pupal body mass as well as pupal and adult body size. Higher larval-rearing temperatures also decreased the lipid and carbohydrate content of the pupae but increased their soluble protein content and adult egg production. These results suggest that the life-history traits and fecundity of H. cunea are plastic. This information is crucial for better understanding the dispersal adaptation strategies of H. cunea and for improving the prediction of population dynamics of this species according to environmental temperatures in different years. Temperature is an important environmental factor influencing the life-history traits of ectotherms. This study investigated the effects of larval-rearing temperature (21, 23, 25, and 27 °C) on the life-history traits and adult fitness of the fall webworm, Hyphantria cunea, an economically important invasive pest of China. With the increase in temperature during the larval stage, the larval developmental duration was significantly shortened, and the body mass was significantly increased, as was that of the body mass and size of pupae. The carbohydrate and lipid content of pupae significantly decreased with increasing larval-rearing temperature, whereas the protein content significantly increased. Adult body size and egg production increased significantly with increasing larval-rearing temperature, whereas there was no significant difference in egg diameter. These results indicate that H. cunea demonstrates life-history traits plasticity. In addition, the increase in fecundity would maintain a stable population size of H. cunea under higher temperatures. Such characteristics could enable H. cunea to spread to the more southern, warmer areas of China, posing an increased risk to the forestry industry in these regions. [ABSTRACT FROM AUTHOR]

Ectothermic animals like amphibians have unique life histories that are impacted by a variety of eco-geographical variables. In this study, the impacts of altitude, which is one of the most frequently used parameters, were examined concerning the age structure, age upon attaining sexual maturity, sexual dimorphism, and growth of two populations of marsh frogs (Pelophylax ridibundus) living at different elevations. The maximum lifespan was 13 years, the highest lifespan ever recorded for P. ridibundus, in the high-altitude population (Sultansazlığı), while it was eight years in the low-altitude population (Ulubağ). In this study, we estimated that individuals living at low altitudes generally reach sexual maturity at the end of their 2nd or 3th year, while individuals living at high altitudes reach sexual maturity approximately one year later. Our results indicated that the population living in the high-altitude site has an average larger body size, higher age, and body weight compared to the population living in the low-altitude site. [ABSTRACT FROM AUTHOR]

The aim of our work was to experimentally test the hypothesis that changes in the thermal stratification in lakes of the temperate zone, expected as a result of progressive global warming, will cause an increase in fitness costs in a planktonic cladoceran Daphnia, associated with diel vertical migrations. In a programmable thermostatic chamber, Daphnia magna have been cultured from the first juvenile instar till the first reproduction, in thermal regimes corresponding to the conditions experienced by non-migratory (remaining in epilimnion day and night) and migrating (spending nights in epilimnion and days in hypolimnion) animals. We exposed Daphnia to thermal regimes: corresponding to the temperatures typically reigning stratified lakes nowadays (20 °C in epilimnion and 8 °C in hypolimnion), and expected at the end of this century (28 °C and 12 °C, respectively). The analysis of life-history parameters confirmed the assumption of an increase in metabolic costs resulting from vertical migration of Daphnia along with the expected increase in temperature differences between epilimnion and hypolimnion, which is a daily anti-predator refuge for migrating animals. This may consequently lead to significant changes in the composition of lake zooplankton communities, i.e., to an increase in the share of non-migrating species with small body sizes. [ABSTRACT FROM AUTHOR]

Flowering phenology is important in the adaptation of many plants to their local environment, but its adaptive value has not been extensively studied in herbaceous perennials. We used Arabis alpina as a model system to determine the importance of flowering phenology to fitness of a herbaceous perennial with a wide geographical range. Individual plants representative of local genetic diversity (accessions) were collected across Europe, including in Spain, the Alps and Scandinavia. The flowering behaviour of these accessions was documented in controlled conditions, in common-garden experiments at native sites and in situ in natural populations. Accessions from the Alps and Scandinavia varied in whether they required exposure to cold (vernalization) to induce flowering, and in the timing and duration of flowering. By contrast, all Spanish accessions obligately required vernalization and had a short duration of flowering. Using experimental gardens at native sites, we show that an obligate requirement for vernalization increases survival in Spain. Based on our analyses of genetic diversity and flowering behaviour across Europe, we propose that in the model herbaceous perennial A. alpina, an obligate requirement for vernalization, which is correlated with short duration of flowering, is favoured by selection in Spain where the plants experience a long growing season. [ABSTRACT FROM AUTHOR]

Developmental plasticity can help organisms to survive in temporally variable environments. However, it is not well understood how variation in life history plasticity helps species coexist in heterogeneous environments. Here, we investigate the extent to which life‐history plasticity explains species distributions in a diverse assemblage of odonates in a tropical freshwater rock pool system characterized by substantial variation in pond permanence. Some dragonflies and damselflies (Odonata) can accelerate their development to leave the water before their habitat dries. However, how they sense habitat drying is poorly understood.Here, we experimentally tested the extent to which elevated concentrations of salts in water or reductions in water level can be used as cues for developmental acceleration in a neotropical Odonata assemblage from granite rock pools.Libellulidae dragonflies were found along the permanence gradient and accelerated their growth in response to elevated dissolved salts (measured as conductivity). Anax amazili (Aeshnidae) was also found in all environments and did the same in response to lower water levels. In turn, larvae of the damselfly Telebasis simulata (Coenagrionidae) were restricted to deeper long‐lived pools and did not respond to the tested cues.Differentiation in life‐history strategies can contribute to niche differentiation in this diverse predator assemblage. Developmental plasticity triggered by different cues helps odonates avoid mortality and exploit short‐lived habitats. The global acceleration of freshwater salinisation due to human activities might disrupt the delicate links between low levels of dissolved salts and life‐history responses and represent a significant threat to these ecosystems and their biodiversity. [ABSTRACT FROM AUTHOR]

Many organisms live in fragmented populations, which has profound consequences on the dynamics of associated parasites. Metapopulation theory offers a canonical framework for predicting the effects of fragmentation on spatiotemporal host–parasite dynamics. However, empirical studies of parasites in classical metapopulations remain rare, particularly for vector-borne parasites. Here, we quantify spatiotemporal patterns and possible drivers of infection probability for several ectoparasites (fleas, Ixodes trianguliceps and Ixodes ricinus) and vector-borne microparasites (Babesia microti , Bartonella spp., Hepatozoon spp.) in a classically functioning metapopulation of water vole hosts. Results suggest that the relative importance of vector or host dynamics on microparasite infection probabilities is related to parasite life-histories. Bartonella , a microparasite with a fast life-history, was positively associated with both host and vector abundances at several spatial and temporal scales. In contrast, B. microti , a tick-borne parasite with a slow life-history, was only associated with vector dynamics. Further, we provide evidence that life-history shaped parasite dynamics, including occupancy and colonization rates, in the metapopulation. Lastly, our findings were consistent with the hypothesis that landscape connectivity was determined by distance-based dispersal of the focal hosts. We provide essential empirical evidence that contributes to the development of a comprehensive theory of metapopulation processes of vector-borne parasites. [ABSTRACT FROM AUTHOR]

Assortative mating, where individuals non‐randomly mate with respect to phenotype or genotype, can occur when preferences between potential mates have evolved. When such mate preferences occur in a population it can drive evolutionary and phenotypic divergence. But the extent to which assortative mating, mate preference, and development are evolutionarily linked remains unclear. Here we use Streblospio benedicti, a marine annelid with a rare developmental dimorphism, to investigate if mate‐choice could contribute to developmental evolution. For S. benedicti two types of ecologically and phenotypically similar adults persist in natural populations, but they give rise to distinctly different offspring with alternative life‐histories. This dimorphism persists despite the absence of post‐zygotic reproductive barriers, where crosses between the developmental types can produce phenotypically intermediate offspring. How this life‐history strategy evolved remains unknown, but assortative mating is a typical first step in evolutionary divergence. Here we investigate if female mate‐choice is occurring in this species. We find that mate preferences could be contributing to the maintenance of alternative developmental and life‐history strategies. Research highlights: It is rare to find an organism that has two types of development within a species. We use such a system to investigate if mate preference between the developmental types is a possible mechanism to create or reinforce population diversification. [ABSTRACT FROM AUTHOR]

Despite host‐fungal symbiotic interactions being ubiquitous in all ecosystems, understanding how symbiosis has shaped the ecology and evolution of fungal spores that are involved in dispersal and colonization of their hosts has been ignored in life‐history studies. We assembled a spore morphology database covering over 26,000 species of free‐living to symbiotic fungi of plants, insects and humans and found more than eight orders of variation in spore size. Evolutionary transitions in symbiotic status correlated with shifts in spore size, but the strength of this effect varied widely among phyla. Symbiotic status explained more variation than climatic variables in the current distribution of spore sizes of plant‐associated fungi at a global scale while the dispersal potential of their spores is more restricted compared to free‐living fungi. Our work advances life‐history theory by highlighting how the interaction between symbiosis and offspring morphology shapes the reproductive and dispersal strategies among living forms. [ABSTRACT FROM AUTHOR]

Copyright of Ornithological Applications is the property of Oxford University Press / USA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In efforts to prevent extinction, resource managers are often tasked with increasing genetic diversity in a population of concern to prevent inbreeding depression or improve adaptive potential in a changing environment. The assumption that all small populations require measures to increase their genetic diversity may be unwarranted, and limited resources for conservation may be better utilized elsewhere. We test this assumption in a case study focused on the peregrine falcon (Falco peregrinus), a cosmopolitan circumpolar species with 19 named subspecies. We used whole‐genome resequencing to generate over two million single nucleotide polymorphisms (SNPs) from multiple individuals of all peregrine falcon subspecies. Our analyses revealed extensive variation among subspecies, with many island‐restricted and nonmigratory populations possessing lower overall genomic diversity, elevated inbreeding coefficients (FROH)—among the highest reported, and extensive runs of homozygosity (ROH) compared to mainland and migratory populations. Similarly, the majority of subspecies that are either nonmigratory or restricted to islands show a much longer history of low effective population size (Ne). While mutational load analyses indicated an increased proportion of homozygous‐derived deleterious variants (i.e., drift load) among nonmigrant and island populations compared to those that are migrant or reside on the mainland, no significant differences in the proportion of heterozygous deleterious variants (i.e., inbreeding load) was observed. Our results provide evidence that high levels of inbreeding may not be an existential threat for some populations or taxa. Additional factors such as the timing and severity of population declines are important to consider in management decisions about extinction potential. [ABSTRACT FROM AUTHOR]

Regional populations of geographically widespread species may respond to different environmental factors across the species' range, generating divergent effects of climate change on life‐history phenology. Using thousands of citizen science observations extracted from iNaturalist and associated with corresponding temperature, precipitation, elevation, and daylength information, we examined the drivers of adult mating and of nymphal phenology, development, and group size for populations of the large milkweed bug, Oncopeltus fasciatus, in different ecoregions. Research‐grade iNaturalist images were correctly identified 98.3% of the time and yielded more than 3000 observations of nymphal groups and 1000 observations of mating adults spanning 18 years. Mating phenology showed distinct regional patterns, ranging from year‐round mating in California to temporally restricted mating in the Great Lakes Northeastern Coast ecoregion. Relative temperature increases of 1°C for a given daylength expanded the mating season by more than a week in western ecoregions. While increases in relative temperature delayed mating phenology in all ecoregions, greater winter precipitation advanced mating in the California ecoregion. In the eastern ecoregions, nymphal phenology was delayed by increases in summer rainfall but was advanced by relative temperature increases, whereas in western regions, relative temperature increases delayed nymphal phenology. Furthermore, accumulated growing degree days (AGDD) was a poor predictor of developmental progression, as we found a positive but weak correlation between AGDD and age structure only for the Appalachian Southeast North America and the Great Lakes Northern Coast ecoregions. These complex phenological responses of O. fasciatus are just one example of how populations may be differentially susceptible to a diversity of climatic effects; using data across a species' whole distribution is critical for exposing regional variations, especially for species with large, continental‐scale ranges. This study demonstrates the potential of photodocumented biodiversity data to aid in the monitoring of life history, host plant–insect interactions, and climate responsiveness. [ABSTRACT FROM AUTHOR]

Chemical analysis of calcified structures continues to flourish, as analytical and technological advances enable researchers to tap into trace elements and isotopes taken up in otoliths and other archival tissues at ever greater resolution. Increasingly, these tracers are applied to refine age estimation and interpretation, and to chronicle responses to environmental stressors, linking these to ecological, physiological, and life-history processes. Here, we review emerging approaches and innovative research directions in otolith chemistry, as well as in the chemistry of other archival tissues, outlining their value for fisheries and ecosystem-based management, turning the spotlight on areas where such biomarkers can support decision making. We summarise recent milestones and the challenges that lie ahead to using otoliths and archival tissues as biomarkers, grouped into seven, rapidly expanding and application-oriented research areas that apply chemical analysis in a variety of contexts, namely: (1) supporting fish age estimation; (2) evaluating environmental stress, ecophysiology and individual performance; (3) confirming seafood provenance; (4) resolving connectivity and movement pathways; (5) characterising food webs and trophic interactions; (6) reconstructing reproductive life histories; and (7) tracing stock enhancement efforts. Emerging research directions that apply hard part chemistry to combat seafood fraud, quantify past food webs, as well as to reconcile growth, movement, thermal, metabolic, stress and reproductive life-histories provide opportunities to examine how harvesting and global change impact fish health and fisheries productivity. Ultimately, improved appreciation of the many practical benefits of archival tissue chemistry to fisheries and ecosystem-based management will support their increased implementation into routine monitoring. [ABSTRACT FROM AUTHOR]

Environmental changes along an altitudinal gradient can facilitate the differentiation of life-history features in ectothermic species, but little attention has been devoted to the reciprocal influence of altitude and alpine slope directionality on life-history variation. According to life-history theory, increased environmental stress causes a change in reproductive allocation from number to quality of offspring, as well as a stronger trade-off between size and number of offspring. To clarify the influence of environmental pressures on the life-history features of the Qinghai toad-headed lizard Phrynocephalus vlangalii along an altitudinal cline, we surveyed late pregnant females from 3 populations of low (2,600 m), middle (3,400 m), and high (3,600 m) elevations in the Dangjin Mountain of Gansu, China from July to October 2019, and compared their inter-population differences in maternal body size, reproductive characteristics, offspring growth, and locomotor performance. Because of lower temperatures, higher humidity, and lower light intensity caused by slope aspect and altitude, the middle-altitude region experienced stronger environmental stress than the high- and low-altitude regions. Our results showed that females were larger at middle- and high-altitude sites and smaller at the low-altitude site, following Bergmann's rule. We also found that females from low-altitude population gave birth earlier than those from the middle and high altitudes. Our results showed a shift in the offspring size-number trade-off of P. vlangalii in response to colder and harsher environments, with lizards from the alpine steppe (i.e. the middle- and high-altitude habitats) producing fewer but larger offspring than those from the warm steppe (i.e. the low-altitude habitat). Low-altitude juveniles grew faster than high-altitude ones, but at the same rates as middle-altitude juveniles. This result demonstrates that the growth of P. vlangalii was associated with temperature and light intensity. Our findings contribute to enhancing our understanding of the altitudinal variation in life-history features of plateau ectotherms and their phenotypic plasticity or local adaptation. [ABSTRACT FROM AUTHOR]

Gracilaria edulis is one of the most studied agarophytes, especially in tropical regions like India because of its natural abundance. Apart from the Indian peninsula, it is widely distributed in tropical and subtropical regions. The taxonomy of G. edulis is evolving; currently G. edulis is the taxonomically accepted name, however several phylogenetic and morphological investigations supported its inclusion in the genus Hydropuntia. In addition to the conventional farming methods like the tube net and raft methods which use clonally propagated seed material, spore-based planting materials like carpospores have been employed to cultivate G. edulis. Co-cultivation with shrimp farm wastewater has also been practised to make the cultivation economically viable and environmentally sustainable as the seaweed could provide an efficient ecosystem service by up taking nitrogen from the shrimp waste. Like other seaweed cultivation systems, farming of G. edulis is also infested by various epiphytes like Ulva, Cladophora, Ceramium, Centroceras, Hypnea and Padina as well as grazed by fishes like Monodactylus, Pelates and Pteroscirtes which decrease the growth and ultimately result in low yield of agar, seaweed sap and other value added products. Food grade agar produced by this seaweed is an important resource and the current review focusses on the latest extraction technologies. Further, there also is evidence based application of plant bio-stimulant derived from G. edulis feedstock which has proven to be highly effective in enhancing the yield by 10–33% in field trials of nine cash crops. [ABSTRACT FROM AUTHOR]

Understanding growth rates and other basic life-history information of imperilled species is essential to assessing the extent of threats to a population, but often difficult due to limited access to study subjects. Here we used mark-recapture data to estimate growth rates of juvenile Critically Endangered green sawfish (Pristis zijsron) in a globally important nursery in the eastern Indian Ocean (Western Australia). Our results suggest that growth of juvenile sawfish in this part of the central Western Australian coast is significantly slower compared to populations on the north-eastern coast of Australia. Additionally, growth rates differed between nearby areas within the nursery region, potentially due to differential productivity or anthropogenic effects. Morphological relationships between total length, rostral length, mouth gape, and clasper length are presented, which will allow for greater accuracy in estimating biological parameters in this species, while updated information on size at maturity (> 3200 mm) and size at birth (approximately 750–900 mm) will help to clarify life-history parameters for this data-poor species. Furthermore, there were distinct differences in the number of rostral teeth of green sawfish between this eastern Indian Ocean population and other populations throughout their current distribution, indicating substantial genetic differentiation in this species globally. These results will help to accurately assess growth trajectories and potential impacts of fisheries and other threats to green sawfish. Additionally, results highlight the importance of assessing population-specific growth rates in threatened species and of considering potential long-term life-history impacts of anthropogenic developments and activities. [ABSTRACT FROM AUTHOR]

Copyright of Molecular Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Genetic identity analysis and PIT (passive integrated transponder) tagging were used to examine the freshwater return rates and phenotypic characteristics of n = 1791 downstream migrating juvenile Salmo trutta in the Burrishoole catchment (northwest Ireland) across the period September 2017 to December 2020. In this system, juveniles out‐migrate (move from freshwater into brackish or marine habitats) in every month of the year, with distinct seasonal peaks in spring (March through June; mostly silvered smolts) and autumn (September through December; mostly younger, unsilvered fry or parr). Both types exhibited a sex‐bias towards females, which was stronger in spring (78% females) than in autumn outmigrants (67%). Sixty‐nine returning fish were matched back to previous juvenile outmigrants, and similar return rates were found for spring outmigrants (5.0%), autumn outmigrants (3.3%) and fish that out‐migrated outside of spring or autumn (2.8%). Spring and autumn outmigrants returned at similar dates (typically mid to late July), but autumn fish were away for longer periods (median = 612 days; spring outmigrants = 104 days). Autumn outmigrants were 25% smaller than spring outmigrants at outmigration and 6% smaller on their return, and within both groups smaller/younger outmigrants spent longer away than larger/older outmigrants. Autumn outmigrants were more likely to return unsilvered as "slob" trout (84%) than spring outmigrants (31%), suggesting they make greater use of brackish habitats that might be safer, but less productive, than fully marine habitats. Nonetheless, both types also produced silvered "sea trout" (≥1+ sea‐age), implying neither is locked into a single life‐history strategy. The findings emphasise that autumn outmigrants and the transitional habitats that support their persistence should not be overlooked in salmonid management and conservation. [ABSTRACT FROM AUTHOR]

Biologists have long known that environmental context can create diverse phenotypes from identical genotypes. Thus, cells of the same foetus can grow into various organs depending on the molecular environment. Also, animals of the same genetic heritage can show different behaviours in different environments. Conrad Hal Waddington conceptualized epigenotypes in the 1930s, whereby modifications of genetic material could generate alternative modules of development arising out of nonvariant genetic information. His concept paved the way for a neo‐Darwinian synthesis by creating bidirectionality between the environment and genes.In a completely independent intellectual universe, Richard Dawkins introduced the idea of extended phenotype in the early 1980s. The hypothesis posits that the appropriate phenotype of genetic information is not limited to the organism but can 'extend' beyond the environment. Parasite manipulation of host behaviour presents a dramatic example of such extended phenotypes.In this perspective, we propose a synthesis between the earlier concept of epigenotypes and the later idea of extended phenotypes, namely a novel concept of extended epiphenotypes.Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

SUMMARY: Colpomenia borea sp. nov. is described from Hokkaido, Japan and Magadan, Far East Russia based on morphological observations and molecular analyses using mitochondrial cox3 and chloroplast rbcL genes. This new species is distinguished from other Colpomenia by its small globular to ovoidal thallus up to 5 cm in diameter, and thin thallus membrane composed of a cortex of one to two‐cell layers and a colorless medulla of up to three layers. This species is epiphytic on the brown alga Stephanocystis in areas protected against waves. The life history in culture of C. borea was investigated and the observed life history pattern was similar to those reported in C. peregrina and C. sinuosa. Our phylogenetic analyses supported that C. borea is a distinct species, yet it is more related to C. peregrina than C. sinuosa. [ABSTRACT FROM AUTHOR]

Intraspecific competition at the larval stage is an important ecological factor affecting life‐history, adaptation and evolutionary trajectory in holometabolous insects. However, the molecular pathways underpinning these ecological processes are poorly characterized. We reared Drosophila melanogaster at three egg densities (5, 60, and 300 eggs/mL) and sequenced the transcriptomes of pooled third‐instar larvae. We also examined emergence time, egg‐to‐adult viability, adult mass, and adult sex‐ratio at each density. Medium crowding had minor detrimental effects on adult phenotypes compared to low density and yielded 24 differentially expressed genes (DEGs), including several chitinase enzymes. In contrast, high crowding had substantial detrimental effects on adult phenotypes and yielded 2107 DEGs. Among these, upregulated gene sets were enriched in sugar, steroid and amino acid metabolism as well as DNA replication pathways, whereas downregulated gene sets were enriched in ABC transporters, taurine, Toll/Imd signaling, and P450 xenobiotics metabolism pathways. Overall, our findings show that larval crowding has a large consistent effect on several molecular pathways (i.e., core responses) with few pathways displaying density‐specific regulation (i.e., idiosyncratic responses). This provides important insights into how holometabolous insects respond to intraspecific competition during development. [ABSTRACT FROM AUTHOR]

Personality traits in many taxa correlate with fitness. Several models have been developed to try to explain how variation in these traits is maintained. One model proposes that variation persists because it is linked to trade-offs between current and future adaptive benefits. Tests of this model's predictions, however, are scant in longlived species. To test this model, we studied male chimpanzees living in Gombe National Park, Tanzania. We operationalized six personality traits using ratings on 19 items. We used 37 years of behavioral and genetic data to assemble (1) daily rank scores generated from submissive vocalizations and (2) records of male siring success. We tested whether the association between two personality traits, Dominance and Conscientiousness, and either rank or reproductive success, varied over the life course. Higher Dominance and lower Conscientiousness were associated with higher rank, but the size and direction of these relationships did not vary over the life course. In addition, independent of rank at the time of siring, higher Dominance and lower Conscientiousness were related to higher siring success. Again, the size and direction of these relationships did not vary over the life course. The trade-off model, therefore, may not hold in long-lived and/or slowly reproducing species. These findings also demonstrate that ratings are a valid way to measure animal personality; they are related to rank and reproductive success. These traits could therefore be used to test alternative models, including one that posits that personality variation is maintained by environmental heterogeneity, in studies of multiple chimpanzee communities. [ABSTRACT FROM AUTHOR]

Feeding offspring is a form of care common in animals. How food shapes offspring fitness, and thus selection on parents, is limited by plasticity in offspring growth and development, and such limitation may shape the evolution of parental care. We compared plastic responses to egg feeding, food availability in the nursery, and nursery size in larvae of two poison frogs: Ranitomeya imitator, regularly fed trophic eggs by their mothers in the wild, and R. variabilis tadpoles, which only rarely have the opportunity to consume eggs. Hand‐reared R. imitator, but not R. variabilis, were heavier at metamorphosis when offered eggs. Although R. imitator ate more of the eggs we offered, perhaps explaining this proximately, the greater plasticity of R. imitator persisted when we manipulated the quantity of an egg‐free diet meant to approximate food in a natural nursery. Egg feeding did not influence the length of the larval period, and only tadpole R. variabilis took longer to complete metamorphosis in more food‐rich nurseries, as is predicted for amphibians generally. In large nurseries, individuals of both species spent longer as tadpoles and were heavier at metamorphosis, an effect independent of food, and one that reflects the complex relationship between ecology and amphibian development. These species differences highlight how tadpole traits might constrain the evolution of egg feeding: R. imitator feed eggs to their tadpoles, and their tadpoles, unlike R. variabilis (a presumptive proxy for the non‐feeding ancestor), offer high returns on such investment. Comparative work will offer the exciting opportunity to assess the extent to which egg feeding selected for this growth response to food availability and/or this plasticity facilitated the evolution of care. [ABSTRACT FROM AUTHOR]

In this paper we draw on stories of schooling as told by three transgender secondary school graduates. The study does not aim to be generalizable or 'speak' for the educational experiences of all Australian transgender-identifying students. The study is framed by first person articulations of what a trans-positive educational experience might involve. The paper leverages a life-history approach in which the participants rearticulate the influence that cisnormative school environments and media practices had on their transition timeframes. Throughout the life-history interviews conducted in a focus group, the participants considered the concept of how a trans-positive educational approach could be deployed in schools to develop services and resources that align with the findings of the National LGBTIQ Health Alliance, 2020. [ABSTRACT FROM AUTHOR]

Premise: Researchers often use ecological niche models to predict where species might establish and persist under future or novel climate conditions. However, these predictive methods assume species have stable niches across time and space. Furthermore, ignoring the time of occurrence data can obscure important information about species reproduction and ultimately fitness. Here, we assess compare ecological niche models generated from full‐year averages to seasonal models. Methods: In this study, we generate full‐year and monthly ecological niche models for Capsella bursa‐pastoris in Europe and North America to see if we can detect changes in the seasonal niche of the species after long‐distance dispersal. Results: We find full‐year ecological niche models have low transferability across continents and there are continental differences in the climate conditions that influence the distribution of C. bursa‐pastoris. Monthly models have greater predictive accuracy than full‐year models in cooler seasons, but no monthly models can predict North American summer occurrences very well. Conclusions: The relative predictive ability of European monthly models compared to North American monthly models suggests a change in the seasonal timing between the native range to the non‐native range. These results highlight the utility of ecological niche models at finer temporal scales in predicting species distributions and unmasking subtle patterns of evolution. [ABSTRACT FROM AUTHOR]