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Environmental variability can significantly impact individual survival and reproduction. Meanwhile, high population densities can lead to resource scarcity and increased exposure to parasites and pathogens. Studies with insects can offer valuable insights into eco-immunology, allowing us to explore the connections between these variables. Here we use the moth Anticarsia gemmatalis to examine how increases in population density and immunological challenge during the larval stage shape its investment in immune defence and reproduction. Larvae reared at a high population density exhibited greater lytic activity against bacteria compared to those reared at low density, whilst bacterial challenge (i.e. bacteria-immersed needles) also increased lytic activity. There was no interaction between the variables population density and bacterial challenge, indicating that these are independent. Surprisingly, neither increase in lytic activity carried through to activity in prepupal haemolymph. Rearing of larvae at a high density delayed pupation and decreased pupal weight. The immunological stimulus did not significantly influence pupal development. Lower population density as a larva resulted in greater adult weight, but did not significantly influence lytic activity in the eggs or the number of eggs laid. Negative correlations were found between lytic activity in the eggs and the number of eggs, as well as between adult weight and the number of eggs. Overall, this study demonstrates that high population density and immune challenge trigger increased lytic activity in caterpillars, but this effect is transient, not persisting into later stages. The trade-offs observed, such as delayed pupation and reduced prepupal weights under high density, suggest a balancing act between immune investment and developmental aspects. The findings hint at a short-term adaptive response rather than a sustained strategy. The implications of delayed pupation and smaller adult moths could influence the moth's life history strategy, impacting its role in the ecosystem. Further research tracking larval immune investment and subsequent reproductive success will unveil the evolutionary dynamics of this relationship in changing environments.

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Understanding populations' responses to environmental change is crucial for mitigating human-induced disturbances. Here, we test hypotheses regarding how three essential components of demographic resilience (resistance, compensation and recovery) co-vary along the distinct life histories of three lizard species exposed to variable, prescribed fire regimes. Using a Bayesian hierarchical framework, we estimate vital rates (survival, growth and reproduction) with 14 years of monthly individual-level data and mark-recapture models to parameterize stochastic integral projection models from five sites in Brazilian savannas, each historically subjected to different fire regimes. With these models, we investigate how weather, microclimate and ecophysiological traits of each species influence their vital rates, emergent life history traits and demographic resilience components in varying fire regimes. Overall, weather and microclimate are better predictors of the species' vital rates, rather than their ecophysiological traits. Our findings reveal that severe fire regimes increase populations' resistance but decrease compensation or recovery abilities. Instead, populations have higher compensatory and recovery abilities at intermediate degrees of fire severity. Additionally, we identify generation time and reproductive output as predictors of resilience trends across fire regimes and climate. Our analyses demonstrate that the probability and quantity of monthly reproduction are the proximal drivers of demographic resilience across the three species. Our findings suggest that populations surpass a tipping point in severe fire regimes and achieve an alternative stable state to persist. Thus, higher heterogeneity in fire regimes can increase the reproductive aspects and resilience of different populations and avoid high-severity regimes that homogenize the environment. Despite being more resistant, species with long generation times and low reproductive output take longer to recover and cannot compensate as much as species with faster paces of life. We emphasize how reproductive constraints, such as viviparity and fixed clutch sizes, impact the ability of ectothermic populations to benefit and recover from disturbances, underscoring their relevance in conservation assessments.

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Evaluating the fitness of hybrids can provide important insights into genetic differences between species or diverging populations. We focused on surface- and cave-ecotypes of the widespread Atlantic molly Poecilia mexicana and raised F1 hybrids of reciprocal crosses to sexual maturity in a common-garden experiment. Hybrids were reared in a fully factorial 2 × 2 design consisting of lighting (light vs. darkness) and resource availability (high vs. low food). We quantified survival, ability to realize their full reproductive potential (i.e., completed maturation for males and 3 consecutive births for females) and essential life-history traits. Compared to the performance of pure cave and surface fish from a previous experiment, F1s had the highest death rate and the lowest proportion of fish that reached their full reproductive potential. We also uncovered an intriguing pattern of sex-specific phenotype expression, because male hybrids expressed cave molly life histories, while female hybrids expressed surface molly life histories. Our results provide evidence for strong selection against hybrids in the cave molly system, but also suggest a complex pattern of sex-specific (opposing) dominance, with certain surface molly genes being dominant in female hybrids and certain cave molly genes being dominant in male hybrids.

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Resumo Este estudo analisa as histórias de vida de oito jovens vivendo com HIV por transmissão vertical, visando compreender suas percepções marcadas pelo segredo e silêncio sobre suas vivências com o vírus. Realizado em ambulatório especializado no Rio de Janeiro, o estudo adotou como ferramenta de cuidado a dança circular, considerada uma Prática Integrativa e Complementar em Saúde. Utilizando abordagem qualitativa e a História de Vida como método de coleta, o foco foi compreender as experiências dos jovens, não apenas relacionadas à doença, mas também a aspectos cruciais de suas vidas. Participaram do estudo três meninas e cinco meninos, todos cientes de seu diagnóstico. Os principais temas emergentes incluíram dinâmica familiar, conexão com o ambiente escolar, desafios na adesão ao tratamento, idade no momento da revelação do diagnóstico e tempo decorrido desde então. A análise das narrativas desses jovens, permitiu explorar aspectos individuais e sociais da experiência, revelando similaridades e diferenças entre eles. As oficinas de dança circular ofereceram um espaço lúdico para a expressão de emoções e sentimentos por meio dos movimentos corporais, ampliando as perspectivas dos jovens em relação ao futuro.

Abstract This study analyzes the life stories of eight young people living with vertically transmitted HIV in order to understand their perceptions marked by secrecy and silence regarding their experiences with the virus. Conducted at a specialized outpatient clinic in Rio de Janeiro, the study adopted circle dance, a Complementary and Integrative Health Practice, as a care tool. Using a qualitative approach and Life History as a data collection method, the focus was to understand the youth's experiences related to the disease and the crucial aspects of their lives. Three girls and five boys participated in the study, all aware of their diagnosis. The principal emerging themes included family dynamics, school environment connection, challenges in treatment adherence, age at the time of diagnosis disclosure, and time elapsed since then. Analyzing these young people's narratives allowed us to explore individual and social aspects of their experiences, revealing their similarities and differences. The circle dance workshops provided a playful space for expressing emotions and feelings through body movements, expanding young people's perspectives on the future.

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Taylor's power law (TPL) describes the expected range of parameters of the mean-variance scaling relationship and has been extensively used in studies examining temporal variations in abundance. Few studies though have focused on biological and ecological covariates of TPL, while its statistical inherences have been extensively debated. In the present study, we focused on species-specific features (i.e. functional traits) that could be influential to temporal TPL. We combined field surveys of 180 fish species from 972 sites varying from small streams to large rivers with data on 31 ecological traits describing species-specific characteristics related to three main niche dimensions (trophic ecology, life history, and habitat use). For each species, the parameters of temporal TPL (intercept and slope) were estimated from the log-log mean-variance relationships while controlling for spatial dependencies and biological covariates (species richness and evenness). Then, we investigated whether functional traits explained variations in TPL parameters. Differences in TPL parameters among species were explained mostly by life history and environmental determinants, especially TPL slope. Life history was the main determinant of differences in TPL parameters and thereby aggregation patterns, with traits related to body size being the most influential, thus showing a high contrast between small-sized species with short lifespans and large-bodied migratory fishes, even after controlling for phylogenetic resemblances. We found that life history traits, especially those related to body size, mostly affect TPL and, as such, can be determinants of temporal variability of fish populations. We also found that statistical effects and phylogenetic resemblances are embedded in mean-variance relationships for fish, and that environmental drivers can interact with ecological characteristics of species in determining temporal fluctuations in abundance.

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Uca maracoani is a fiddler crab found in estuaries along the western Atlantic coast, with a notable preference for euhaline environments. This study aimed to analyze the population structure and dynamics of this species in an estuary on the North Coast of Brazil, specifically in an area of the upper estuary where seasonal rainfall fluctuations result in significant changes in salinity. Monthly crab samples were taken from December 2013 to November 2015, together with measurements of environmental variables, such as water and climate parameters. The population maintains a balanced sex ratio; however, males are generally larger, with lower mortality rates and longer lifespans than females. Reproduction is continuous but mainly takes place in the dry season when salinity levels are higher (above 12‰). Higher crab densities have been observed during the rainy season when, despite lower salinity levels (below 10‰), the conditions for survival (food availability and milder climate) seem to be more favorable. The estimated average annual biomass and production for the population were 2.62 g AFDM m-2 and 5.43 g AFDM m-2 year-1, respectively, characterized by a high turnover rate (P/B = 2.10 year-1). Our results suggest that U. maracoani has thriving populations in the Amazon coast's mangroves, benefiting from the vast muddy intertidal zone and the high organic content delivered by the estuaries.

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Secondary tropical forests play an increasingly important role in carbon budgets and biodiversity conservation. Understanding successional trajectories is therefore imperative for guiding forest restoration and climate change mitigation efforts. Forest succession is driven by the demographic strategies-combinations of growth, mortality and recruitment rates-of the tree species in the community. However, our understanding of demographic diversity in tropical tree species stems almost exclusively from old-growth forests. Here, we assembled demographic information from repeated forest inventories along chronosequences in two wet (Costa Rica, Panama) and two dry (Mexico) Neotropical forests to assess whether the ranges of demographic strategies present in a community shift across succession. We calculated demographic rates for >500 tree species while controlling for canopy status to compare demographic diversity (i.e., the ranges of demographic strategies) in early successional (0-30 years), late successional (30-120 years) and old-growth forests using two-dimensional hypervolumes of pairs of demographic rates. Ranges of demographic strategies largely overlapped across successional stages, and early successional stages already covered the full spectrum of demographic strategies found in old-growth forests. An exception was a group of species characterized by exceptionally high mortality rates that was confined to early successional stages in the two wet forests. The range of demographic strategies did not expand with succession. Our results suggest that studies of long-term forest monitoring plots in old-growth forests, from which most of our current understanding of demographic strategies of tropical tree species is derived, are surprisingly representative of demographic diversity in general, but do not replace the need for further studies in secondary forests.

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Objetivo: analisar a história de vida de Maria de Colodina, suas interseccionalidades e contribuições para a enfermagem. Métodos: trata-se de pesquisa narrativa biográfica, segundo o referencial de pesquisa social interpretativa alemã da socióloga Gabriele Rosentha. Foi realizada através da análise de documentos históricos fornecidos pelo Museu Nacional de Enfermagem. Os dados foram analisados a partir da análise interpretativa. Resultados: para reconstrução biográfica, utilizamos um quadro com perguntas centrais. Buscamos responder sobre data de nascimento, quem foram os pais, como foi sua infância, adolescência e idade adulta, onde e como envelheceu, seus papéis sociais e principais acontecimentos, e onde e quando morreu. Considerações finais: o processo de apagamento das contribuições de enfermeiras negras/pretas está assentado no sistema de apagamento a partir de estratégias de não reconhecimento desses personagens na construção sócio-histórica da profissão. Permitir que os processos de silenciamento da história sejam descontinuados é um dos objetivos centrais da nova história.

Objective: to analyze Maria de Colodina's life story, her intersectionalities and contributions to nursing. Methods: this is biographical narrative research, according to the German interpretative social research framework by sociologist Gabriele Rosentha. It was carried out through analysis of historical documents provided by the Brazilian National Nursing Museum. The data were analyzed using interpretative analysis. Results: for biographical reconstruction, we used a table with central questions. We sought to answer her date of birth, who her parents were, what her childhood, adolescence and adulthood were like, where and how she grew old, her social roles and main events, and where and when she died. Final considerations: the process of erasing black nurses' contributions is based on an erasure system based on strategies of non-recognition of these characters in the socio-historical construction of the profession. Allowing the processes of silencing history to be discontinued is one of the central objectives of the new history.

Objetivo: analizar la historia de vida de María de Colodina, sus interseccionalidades y aportes a la enfermería. Métodos: se trata de una investigación narrativa biográfica, según el marco de investigación social interpretativa alemana de la socióloga Gabriele Rosentha. Se realizó a través del análisis de documentos históricos aportados por el Museo Nacional de Enfermería. Los datos se analizaron mediante análisis interpretativo. Resultados: para la reconstrucción biográfica se utilizó una tabla con preguntas centrales. Buscamos responder a tu fecha de nacimiento, quiénes fueron tus padres, cómo fue tu niñez, adolescencia y edad adulta, dónde y cómo envejeciste, tus roles sociales y principales acontecimientos, y dónde y cuándo moriste. Consideraciones finales: el proceso de borrado de los aportes de las enfermeras negras se sustenta en el sistema de borrado basado en estrategias de no reconocimiento de estos personajes en la construcción sociohistórica de la profesión. Permitir que se descontinúen los procesos de silenciamiento de la historia es uno de los objetivos centrales de la nueva historia.

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The blue shark is a highly migratory species with a worldwide distribution, making it susceptible to multiple fishing fleets across the globe. In southern Brazil, it is an important target, comprising up to 40% of the total biomass landed by the commercial surface longline fleet. This study aims to contribute to a better understanding of how the species uses the region and to update its life-history information available for future assessments. Over five consecutive years (2018-2022) of landings and onboard monitoring, we gathered size data and vertebral samples to describe the species size composition in the region, as well as its seasonal and interannual variability and to update estimated life-history parameters. The results showed that southern Brazil is mainly inhabited by large juvenile males that arrive during winter (July-September) and stay until spring (October-December), when their frequency decreases. Small adult males are present throughout the year but in higher frequencies during summer. A small number of adult females are present with higher frequencies during spring and summer, which decreases during the austral autumn and winter. Some variability in the presence of each life stage was observed among years. The estimated life-history parameters were as follows: L∞: 255.02 cm fork length (FL), k: 0.20, L0:35.68 cm FL for males; L∞: 246.47 cm FL, k: 0.23, L0:36.77 cm FL for females; and L∞: 269.58 cm FL, k: 0.18, L0:36.19 cm FL for pooled sexes. However, the estimated values must be cautiously interpreted, as the obtained samples cannot be construed as representative of the entire harvested stock due to the lack of consistent presence of some life stages in the study region.

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[This corrects the article DOI: 10.3389/fpls.2023.1276727.].

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The early development of the freshwater fish Rhytiodus microlepis is characterized by the description of external morphological, meristic, and morphometric changes, as well as the growth patterns, thereby establishing a reference for the identification of its larvae and juveniles. Specimens were collected from the Amazon river channel and floodplain. Ninety-seven individuals were analysed with standard length varying between 4.31 and 79.23 mm. Rhytiodus microlepis larvae are altricial, with an elongated and fusiform body, anal opening reaching the middle region of the body, and simple nostrils becoming double and tubular during development. The pigments vary from one to two chromatophores in the dorsal region of the head in pre-flexion and flexion, but later the pigmentation pattern intensifies, transverse bands appear along the body, and a conspicuous spot appears in the basal region of the caudal fin. The total number of myomeres ranges from 49 to 50. During the transition from larval (post-flexion) to the juvenile periods, the most significant anatomical changes occur, such as the presence of all fins and increased body pigmentation. Integrated myomere count and pigmentation pattern are effective for the correct identification of the initial life stages of R. microlepis from the Amazon basin. Our results expand the knowledge about the early life history of Neotropical freshwater fish species.

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Resource allocation in plants is a fundamental aspect of life history theory. In Cactaceae, the specific trade-off between sexual reproduction and vegetative growth has still not been studied. The aim of this work was to assess if there is a trade-off between growth and reproduction, and to analyse whether both growth and allocation to reproduction depend on size of the individual. In this study, we used Gymnocalycium monvillei, a globose cactus endemic to the mountains of central Argentina, as a model species. Specifically, we analysed the relationship of growth (percentage increase in diameter) and size of individuals (diameter) to seed production, seed mass, germination, and mean germination time. To relativize the effect of size on seed production, two variables were calculated: the ratio of seed production to plant size (RSPS), and the ratio of total seed mass to plant size (RSMS). We found that both seed production and total seed mass were significantly related to cactus size. However, growth was not related to seed mass or to seed production, even when they were relativized. Germination and mean germination time were not related to plant size or growth. In the studied species, a slow-growing globose cactus, we did not find a trade-off between growth and reproduction.

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Age and growth-related data are basic biological parameters, essential in population ecology, evolution, and conservation biology. There is a growing body of published information on reptile demography derived from sclerochronology, a technique based on counting the growth layers deposited in bones (skeletochronology) and other hard body structures. Since the data are not always easily available, we compiled the existing published data, described the current status of knowledge, synthetized the conclusions of disparate studies, and identified patterns of research and information gaps, prioritizing the needs for future research. Our database includes the results of 468 published studies covering 236 reptile species from 41 families. These represent less than 2% of the total number of known extant species. Turtles and crocodiles are proportionally better studied, while snakes are the least examined group. The distribution of the research does not reflect conservation needs; we found an important geographic bias, with an overrepresentation of Northern temperate species. Only 23% of the studies checked the assumption of periodicity of growth marks deposition, and the method was found to be reliable or adequate in 79% of the cases. Overall, the data obtained through sclerochronology can be considered robust, especially if validation methods are employed, since the general goal is to characterize population parameters, trends, and dynamics, rather than determining the exact age of any specimen in particular.

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A Resiliência é um processo psicológico que envolve a adaptação positiva diante das adversidades, proporcionando aos indivíduos oportunidades de crescimento e aprendizado. O presente estudo buscou compreender as possíveis relações entre a história de vida de executivos e os comportamentos resilientes demonstrados no ambiente de trabalho. Este estudo é uma pesquisa qualitativa que contou com a participação de executivos de quatro organizações do setor têxtil sediadas no estado de Santa Catarina, Brasil. A coleta de dados foi realizada a partir do método biográfico e de entrevistas semiestruturadas. A análise de conteúdo revelou que a resiliência é um processo aprendido ao longo da vida, o qual auxiliou os participantes a enfrentar e superar as adversidades presentes nos contextos de trabalho em tempos difíceis. Os resultados demonstraram que a resiliência dos executivos teve impacto no alcance dos resultados organizacionais, no desenvolvimento de novas habilidades e na manutenção de sua saúde, bem-estar e qualidade de vida. A resiliência é uma capacidade que pode auxiliar no enfrentamento e superação das adversidades no ambiente de trabalho, especialmente em momentos desafiadores.

Resilience is a psychological process that involves positive adaptation in the face of encoureted adversities, offering individuals opportunities for growth and learning. This study aimed to explore the potential relationships between executives' life histories and the resilient behaviors they exhibit in the workplace. It is a qualitative research conducted with executives from four organizations in the textile sector, based in the state of Santa Catarina, Brazil. Data was collected using biographical methods and semi-structured interviews. Content analysis revealed that resilience is a learned proces that unfolds throughout life, assisting participants in confronting and surmounting the challenges present in work environments during challenging times. The results demonstrated that executives had a significant impact on achieving organizational outcomes, developing new skills, and maintaining their health, well-being, and quality of life. Resilience is a valuable capacity that can aid in facing and surpassing workplace adversities, especially in moments of difficulty.

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RESUMEN En los últimos años se ha evidenciado un notable aumento en las poblaciones de la medusa Lychnorhiza aff. lucerna en el departamento del Magdalena, lo que ha tenido un impacto en la pesca artesanal y el turismo. El conocimiento que se tiene sobre la biología básica de estos organismos sigue siendo limitado, por lo que se hace necesario profundizar en la comprensión acerca de esta medusa y su historia de vida. El objetivo de esta investigación fue realizar ensayos preliminares para evaluar la viabilidad del mantenimiento en cautiverio de la medusa Lychnorhiza aff. lucerna, implementando sistemas de acuarios y estrategias de reproducción que han sido usados en otras especies de medusas. Se realizaron ensayos de fertilización in vitro y la fecundación fue exitosa con la observación de embriones en su primer clivaje. Las medusas fueron mantenidas en cautiverio en sistemas Kreisel por un periodo de 60 días, en este tiempo, las medusas disminuyeron hasta el 30 % de su tamaño. Se confirmó que los acuarios Kreisel y Pseudo-Kreisel son idóneos para el mantenimiento de esta especie filtradora, debido a que proporcionan las condiciones mínimas necesarias para estos organismos.

ABSTRACT In recent years, there has been a noticeable increase in the populations of the jellyfish Lychnorhiza aff. lucerna in the department of Magdalena, Colombia, impacting artisanal fishing and tourism. The understanding of the basic biology of these organisms remains limited, emphasizing the necessity to delve deeper into comprehending this jellyfish and its life history. The aim of this research was to conduct preliminary trials to assess the feasibility of maintaining the jellyfish Lychnorhiza aff. lucerna in captivity by employing aquarium systems and reproduction strategies used in other species of jellyfish. In vitro fertilization trials were conducted, resulting in successful fertilization observed through embryos in their first cleavage. The jellyfish were manteined in Kreisel systems for a 60 days period, during which their size decreased by up to 30%. It was confirmed that Kreisel and Pseudo-Kreisel aquariums are suitable for sustaining this filter-feeding species, as they provide the necessary minimum conditions for these organisms.

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The reproductive mode of viviparity has independently evolved in various animal taxa. It refers to the condition in which the embryos or young develop inside the female's body during gestation, providing advantages such as protection, nutrition, and improved survival chances. However, parasites and diseases can be an evolutionary force that limit the host's resources, leading to physiological, morphological, and behavioral changes that impose additional costs on both the pregnant female and her offspring. This review integrates the primary literature published between 1980 and 2021 on the parasitism of viviparous hosts. We describe aspects such as reproductive investment in females, offspring sex ratios, lactation investment in mammals, alterations in birth intervals, current reproductive investment, variations between environments, immune system activity in response to immunological challenges, and other factors that can influence the interaction between viviparous females and parasites. Maintaining pregnancy incurs costs in managing the mother's resources and regulating the immune system's responses to the offspring, while simultaneously maintaining an adequate defense against parasites and pathogens. Parasites can significantly influence this reproductive mode: parasitized females adjust their investment in survival and reproduction based on their life history, environmental factors, and the diversity of encountered parasites.

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Introduction: The phenomenal expansion of angiosperms has prompted many investigations into the factors driving their diversification, but there remain significant gaps in our understanding of flowering plant species diversity. Methods: Using the crown age of families from five studies, we used a maximum likelihood approach to classify families as having poor, predicted or high species richness (SR) using strict consensus criteria. Using these categories, we looked for associations between family SR and i) the presence of an inferred familial ancestral polyploidization event, ii) 23 life history and floral traits compiled from previously published datasets and papers, and iii) sexual system (dioecy) or genetically determined self-incompatibility (SI) mating system using an updated version of our own database and iv) geographic distribution using a new database describing the global distribution of plant species/families across realms and biomes and inferred range. Results: We find that more than a third of angiosperm families (65%) had predicted SR, a large proportion (30.2%) were species poor, while few (4.8%) had high SR. Families with poor SR were less likely to have undergone an ancestral polyploidization event, exhibited deficits in diverse traits, and were more likely to have unknown breeding systems and to be found in only one or few biomes and realms, especially the Afrotropics or Australasia. On the other hand, families with high SR were more likely to have animal mediated pollination or dispersal, are enriched for epiphytes and taxa with an annual life history, and were more likely to harbour sporophytic SI systems. Mapping the global distribution of georeferenced taxa by their family DR, we find evidence of regions dominated by taxa from lineages with high vs low SR. Discussion: These results are discussed within the context of the literature describing "depauperons" and the factors contributing to low and high biodiversity in angiosperm clades.

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The primary (PSR), secondary (SSR) and adult (ASR) sex ratios of sexually reproducing organisms influence their life histories. Species exhibiting reversed sexual size dimorphism (RSD) may imply a higher cost of female production or lower female survival, thus generating biases in PSR, SSR and/or ASR towards males. The Harpy Eagle is the world's largest eagle exhibiting RSD. This species is found in the Neotropical region and is currently threatened with extinction. We used molecular markers to determine the sex of 309 Harpy Eagles spanning different life stages-eaglets, subadults and adults-from 1904 to 2021 within the Amazon Rainforest and Atlantic Forest. Sex ratios for all life stages revealed a female-biased deviation across all periods and regions. Our results suggest that the population bias towards females is an evolutionary ecological pattern of this species, and SSR and ASR likely emerged from the PSR. This natural bias towards females may be compensated by an earlier sexual maturation age of males, implying a longer reproductive lifespan and a higher proportion of sexually active males. A better understanding of the Harpy Eagle's life history can contribute to understanding sex-role evolution and enable more appropriate conservation strategies for the species.

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We provide the first evidence for hemoparasites in the endemic Cordoba treefrog Boana cordobae. We collected 37 adult frogs at 1200 m a.s.l. in the Comechingones Mountains in the Córdoba province (Argentina). Each individual was sexed, then snout-vent length and body mass were recorded, a toe was collected for skeletochronological age determination, and a slide with a blood smear was prepared for hemoparasite screening, before releasing the frogs in situ. A total of 81% (n = 30) of the frogs were infected by hemogregarines and trypanosomes with a high intensity of infections. Dactylosoma was found for the first time in Argentina. Hemoparasites had no significant effect on the leukocyte profile, which we assessed from the May-Grünwald-Giemsa-stained blood smears. The neutrophils/lymphocytes ratio, indicative of stress, was insignificantly higher (0.06) in parasitized frogs than in parasite-free individuals (0.04). Infected frogs were larger than the controls, but this effect vanished when correcting size data for age. Young frogs (first-breeders) dominated the age distribution of parasite-free individuals, suggesting that infection of frogs takes usually place after sexual maturation. Vectors transmitting hemoparasites to B. cordobae remain to be identified. We demonstrate that moderate to high intensities of hemoparasites do not significantly affect the cellular immune response of B. cordobae, or any of the life-history traits studied, nor did they show any external sign of disease.

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We report a case of predation on the basket worm Oiketicus sp. (Lepidoptera, Psychidae) by the Streak-backed Oriole (Icterus pustulatus) in the Municipality of Santa Cruz Xoxocotlán, Oaxaca, Mexico. The bird was photographed, and we describe the prey based on its basket, cephalic capsule, and fragments of thoracic segments. We describe the foraging strategy and provide a list of previously recorded food resources in the diet of I. pustulatus. This is the first documentation of a basket worm being consumed by I. pustulatus, which may be considered omnivorous.

Reportamos un caso de depredación sobre el gusano canasta Oiketicus sp. (Lepidoptera, Psychidae) por la calandria dorso rayado (Icterus pustulatus) en el Municipio de Santa Cruz Xoxocotlán, Oaxaca, México. El ave fue fotografiada y describimos la presa a partir de su canasta, cápsula cefálica y fragmentos de segmentos torácicos. Describimos la estrategia de forrajeo y presentamos una lista de recursos alimentarios previamente registrados en la dieta de I. pustulatus. Esta es la primera documentación de alimentación de un gusano canasta por parte de I. pustulatus, el cual puede ser considerada omnivora.