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Article
Biology and Life Sciences
Ecology, Evolution, Behavior and Systematics

Juliette Le Lepvrier-Cussol

,

Julia Meunier

,

Aurore Ponchon

Abstract: The ongoing expansion of Highly The ongoing expansion of Highly Pathogenic Avian Influenza Virus (HPAIV) H5N1 is driving unprecedented wildlife mortality and raising global health concerns. To date, Oceania remains the last region free of HPAIV, offering a critical opportunity to anticipate and mitigate future emergence. Here, we assess the risk of HPAIV introduction and spread within seabird communities of New Caledonia, a key biodiversity hotspot of the South Pacific located along major transoceanic migratory routes. We compiled a comprehensive list of seabird species previously exposed to HPAIV and evaluated their likelihood of occurrence in New Caledonia using literature and global biodiversity databases. Species were classified as breeding or non-breeding, and their potential roles in virus dynamics were quantified using trait-based indices. Additionally, seabird migratory connectivity between New Caledonia and surrounding regions was estimated. Among 71 retained seabird species, several long-distance migrant species—particularly within Procellariidae and Charadriiformes—emerged as potential high-risk vectors, although often with low probability of occurrence locally. In contrast, highly colonial breeding species, including Thalasseus bergii and Fregata minor, showed the greatest potential to amplify local transmission. Network analyses revealed that the strongest ecological connections occur with nearby regions not yet affected by HPAIV, whereas links to infected areas involve distances > 2000 km, potentially constraining virus emergence in the South Pacific. Our results identify priority species and critical knowledge gaps, providing a framework to guide targeted surveillance and proactive management strategies in the South Pacific.

Article
Biology and Life Sciences
Ecology, Evolution, Behavior and Systematics

Motti Charter

Abstract: School-based citizen science is increasingly used to support biodiversity monitoring, but the reliability of student-generated ecological data remains uncertain. We evalu-ated a nationwide barn owl (Tyto alba) pellet project in Israel involving 1,612 students and 107 teachers over two academic years. Teacher participation was moderate to high: 66.4% of teachers returned at least one complete kit, generating 3,333 prey rec-ords—mostly from small mammals—and demonstrating that schools can contribute significant ecological sampling effort across broad geographic areas. Student identifi-cation accuracy was moderate: 50% of pellet analyses were perfectly identified, with an overall item-level accuracy of 62%, and 76% of pellet attempts included at least one correctly identified prey item. The probability of perfect identification declined sharply with pellet complexity. Each additional prey item reduced the odds of correctly identi-fying all prey items in a pellet by about 68%, indicating that identification reliability decreases as sample complexity increases. Although many students initially found pellets disgusting, engagement remained high, and willingness to repeat the activity was strongly linked to enjoyment. These findings show that school-based citizen sci-ence can support biodiversity monitoring, but reliable ecological inference requires validation frameworks, especially when sample complexity is high.

Article
Biology and Life Sciences
Ecology, Evolution, Behavior and Systematics

Victor V. Aleksanov

,

Cyrill E. Garanin

Abstract: (1) Pholidoptera griseoaptera (De Geer, 1773) (Orthoptera, Tettigoniidae) is known as a common and widespread inhabitant of forest edges in Europe, so it may be a suitable model to understand a dealing of forest wildlife in the past and the future. (2) We registered the presence or absence of the species in 189 edge/forest plots in the Kaluga Region using acoustic observations and pitfall traps, and performed a logit regression. (3) Across the region, the main factor that positively affected the presence of the species was the presence of nemoral herbs as dominants of the herb layer. The main negative factors were the isolation of habitat patches by physical barriers and belonging to the moraine plains of the last stage of the Moscow glaciation. The presence of coniferous species in the tree layer and spatial autocovariation were significant factors with small contributions. Abundance of Ph. griseoaptera was higher in the forest located in the river valleys. Across Kaluga City, the long existence of tree vegetation in place of plots and the isolation were the main significant factors affecting the presence of the species. The smallest urban site where the species lives is about 13 ha, and the summary square of unmowed patches in this habitat is about 0.2 ha. (4) Ph. griseoaptera can be used as a marker of the persistence of the broadleaved deciduous (nemoral) forests in the past. In a high level of urbanization, it can become a threatened species.

Article
Biology and Life Sciences
Ecology, Evolution, Behavior and Systematics

David Brailovsky-Signoret

,

Héctor M. Hernández

,

Gabriela Castaño-Meneses

Abstract: North America´s largest semi-arid lands form the Chihuahuan Desert Biome, which had fluctuated between Interglacial and Glacial conditions for eight million years. Cacti prob-ably came from South America after substantial distancing from Africa, and pollen fossils reveal their arrival in Mexico some 51.6 Ma. We have examined distributions of 119 strict-ly endemics (36.17 % of overall 329 species) and model 75 species represented in well de-fined and relatively large disjunct area groups. We modeled Species Distribution Models (SDMs) using MAXENT algorithms for present and past climates for the region, following our detailed models on climate after Sánchez-Santillán and García detailed numerical methods and Co-Kriging tools. Scotese, Van Devender, Betancourt, and Roy-Priyadarsi were utilized for modelling the glacial part. A total of 4030 registers were sampled from the Central America and North America Cacti Database (UNAM), a comprehensive set of hard information from 68 herbaria and containing over 62,000 vouchers. Registers com-prised 3719 modelable species´ specimens. Track and node analyses were applied using PANBIOTRACKS. We identified the colonization patterns and general evolutionary trends for the species. We modeled detailed combined layers of idoneity and overlap them to tracks and nodes in order to detect biogeographic trends and patterns.

Article
Biology and Life Sciences
Ecology, Evolution, Behavior and Systematics

Joaquín L. Reyes-López

Abstract: The delimitation of cryptic species represents one of the main challenges, particularly in groups with low external morphological differentiation. In this context, scanning electron microscopy (SEM) enables the detection of diagnostic characters at the microscale. This study evaluates the potential of ocular morphology for interspecific discrimination within a group of species of the genus Temnothorax. A total of 246 workers from 52 nests, 13 populations, and 8 species from the Iberian Peninsula and North Africa were analyzed. Morphometric variables related to compound eyes were quantified from SEM images (ommatidia number, interommatidial setae, eye diameter). Data were analyzed using ANOVA, effect size estimation (η²), Linear Discriminant Analysis (LDA), and Random Forest models. All variables showed significant differences among species (p < 0.001), with varying discriminative power. Variables related to ommatidial organization exhibited the highest classification performance, achieving high rates of correct species assignment in multivariate analyses. The use of nest-level means values substantially improved classification accuracy. These results demonstrate that ocular morphology analyzed through SEM represents a promising complementary tool for species discrimination in Temnothorax, complementing traditional and molecular approaches.

Article
Biology and Life Sciences
Ecology, Evolution, Behavior and Systematics

Suresh Puthumana

,

Gustavo A. Londoño

,

Leanne M. Diss

,

Adam Salyer

,

Julie M. Allen

,

Mohamed F. Sallam

Abstract: To understand tropical avian ectoparasitism, we analyzed bird–tick data and remote-sensing habitat metrics across the Colombian Andes (2008-2019), sampling 1,164 birds (204 species) across 15 localities (538-3121 m a.s.l.). Macrohabitat variables, land use/land cover (LULC), forest structure, and bioclimatic data were derived from Sentinel-2/CIAT raster products (5 km buffers); microhabitat variables comprised avian morphological and behavioral traits. Random Forest Models (RFMs) linked host and habitat factors to tick presence. Tick prevalence and host assemblages varied significantly by elevation and Andean region. Eastern Andean sites had the highest bird richness and tick infestation rates, whereas middle elevations had the lowest. Remote sensing revealed major LULC shifts over the study period. Forest decline and increased cropland/grassland, especially in the Western Andes, while Eastern sites showed a mixture of habitat loss and recovery. Macrohabitat models identified elevation and vegetation structure (Barren/Sparse vegetation, Closed shrublands) as strong predictors of tick presence (AUC = 95; R² = 62.3%). Microhabitat models highlighted host behavior and morphology (mixed-flock participation, bill shape, foraging strata) (AUC = 82.5%). The integrated model performed best (AUC = 98; R² = 76.4%), confirming that tick–bird dynamics are driven by combined environmental gradients and host traits. Our findings emphasize the value of multi-scale, remote-sensing-informed frameworks for predicting ectoparasite risk in complex tropical systems.

Review
Biology and Life Sciences
Ecology, Evolution, Behavior and Systematics

Noah Lemke

,

Nalini Puniamoorthy

Abstract:

The black soldier fly (BSF; Hermetia illucens) is rapidly emerging as a model for evolutionary biology and insect biotechnology. Although larval biology has been extensively characterised, the reproductive biology of adults remains comparatively understudied. In this review, we synthesise the most recent empirical work on physiology, behavioural and chemical ecology to open the “black box” of BSF reproduction, focusing on processes that span eclosion to senescence. We highlight pre- and post-mating mechanisms that determine overall reproductive fitness: from mating latency, lekking dynamics, courtship and copulation, to sperm transfer, storage and oviposition. We discuss these processes within the framework of sexual selection theory. Several notable characteristics of BSF reproduction differ from traditional insect models. These include a hybrid capital-income breeding strategy (adults do not need to feed but can benefit from supplemental nutrition), protandry (early male emergence), sex-specific longevity that varies with mating status and a lek-like mating system. In addition, females possess morphologically complex sperm‑storage organs, providing ample opportunity for intense post‑copulatory sexual selection. Recent work shows that environmental factors such as light, humidity, temperature, substrate volatiles and rearing design strongly influence reproductive output in industrial settings, highlighting the potential for BSF to bridge fundamental and applied research. We propose a novel conceptual framework that integrates these elements and outline key unresolved questions (e.g., mechanisms of sperm precedence, female control of fertilization, reproductive barriers, drivers of speciation etc.). This interdisciplinary model supports both fundamental insights into the evolution of reproductive traits and provides practical improvements for optimizing industrial mass-rearing.

Article
Biology and Life Sciences
Ecology, Evolution, Behavior and Systematics

Richard H. Zander

Abstract: Macroevolutionary analysis evaluating structural monophyly as descent with modification allows recasting of taxa in terms of physics, here named evolutionary mechanics. There are four natural taxa: the species, genus, lineage and metalineage, each modeling distinctive evolutionary processes. The species is the smallest group whose traits exclude a two-sigma conduit of uncertainty through spacetime and otherwise are demonstrably active in processes at the genus level. The genus is a complex engine using the Rule of Four and the Pareto Fractal Dimension to fashion and control changes over time in minimally monophyletic groups. A Rule of Eight for extinction is based on exhaustion of kinetic energy. The lineage is modeled as a caulogram, a stem-taxon tree of present-day species and genera arranged in timelike sequence. The metalineage is an informationally structured n-tuple set of caulograms for one lineage as calculated at successive times in the past following a strict morphological clock. Values associated with evolutionary processes are calculated and compared for two bryophyte lineages at species, genus and lineage levels. These comparisons include Punctuational Impulse, Constant of Resistance, Efficiency Ratio, and Evolutionary Force, as well as analogues of classical mechanics: evolutionary distance, velocity, acceleration, force, work, and kinetic energy. Metalineages reveal sustained similar numbers of species across ca. 100 million years.

Article
Biology and Life Sciences
Ecology, Evolution, Behavior and Systematics

Zerihun Asrat

,

Mekbib Fekadu

,

Zerihun Woldu

,

Sebsebe Demissew

,

Betelhem Mekonnen

,

Lars Opgenoorth

,

Georg Miehe

,

Wolfgang Zech

Abstract: Soil organic matter (SOM) dynamics in highaltitude tropical ecosystems are poorly understood, yet critical for predicting carbon-climate feedbacks. We characterized SOM pools in the Bale Mountains National Park (Ethiopia) across vegetation types (Ericaceous belt, fragmented Ericaceous belt, Afroalpine heathland, giant Lobelia area), fire histories (recently burned, 10–25 years post-fire, unburned >25 years), and topographic positions. Using physical fractionation, we separated coarse (149–2000 μm) and fine (53–149 μm) particulate organic matter (POM) and mineral-associated organic matter (MAOM, < 53 μm). Particulate organic matter dominated the SOM pool (>99%), with C representing only 0.05–0.07% of total organic carbon. The Ericaceous belt had the highest coarse POM (11.38 g kg⁻¹), while the fragmented Ericaceous belt showed the lowest (8.96 g kg⁻¹, p = 0.042). Intermediate fire disturbance (10–25 years) increased coarse and fine POM by ~12–13% compared to recently burned or long-unburned sites. Topographic position significantly influenced POM fractions, with northern slopes accumulating the highest amounts (p <  0.05). Cation exchange capacity was strongly positively correlated with POM fractions (r = 0.86, p <  0.001), while elevation showed a negative relationship (r = –0.38, p = 0.04). The extremely low proportion of MAOM suggests limited long-term stabilization capacity, making these soils vulnerable to warming-induced decomposition. Our results demonstrate that fire history, vegetation, and topography interact to control SOM dynamics, and that conservation strategies should prioritize minimizing anthropogenic disturbance to preserve SOM inputs and ecosystem resilience.

Review
Biology and Life Sciences
Ecology, Evolution, Behavior and Systematics

Leandro Lofeu

,

Ehsan Pashay Ahi

Abstract: Biomonitoring has been transformed by high-throughput sequencing from morphology-based indices to scalable molecular inventories, yet monitoring has remained dominated by taxa lists. In this Perspective, Biomonitoring 3.0 is proposed as interaction-ready, time-resolved ecosystem monitoring, with environmental RNA positioned as a complementary layer through which more recent biological activity and context-dependent responses can often be reported. An inference ladder is introduced to grade interaction evidence from co-occurrence patterns to coupled signal–response dynamics and, where feasible, ecosystem-level consequences. Field designs are outlined in which time-lagged series, paired sampling of signal sources and putative recipients, and carrier-aware handling of extracellular RNA are emphasized to reduce legacy detection and strengthen attribution. Minimum reporting elements are recommended to support cross-study synthesis and benchmarking. The “3.0” designation is justified as a third step beyond Biomonitoring 2.0 inventories: monitoring is redirected from static membership toward dynamics and feedbacks that govern ecosystem function and decision-relevant change. A pragmatic agenda is provided for converting environmental nucleic acids into interaction indicators rather than presence records.

Review
Biology and Life Sciences
Ecology, Evolution, Behavior and Systematics

John S. Richardson

Abstract: Frequent observations suggest that headwater streams have lower species diversity within a site than larger streams, but higher beta diversity, and thus gamma diversity, across a catchment. This pattern of diversity includes taxonomic richness and genetic diversity. There are several mechanisms that potentially contribute to the overall high diversity of freshwater organisms in headwaters, although these mechanisms are interdependent. Here I review those mechanisms in an attempt to isolate each and review the available evidence. These include the high numbers of headwater streams, heterogeneity of habitats and resources, founder effects, colonization dynamics, isolation, and strong selection, all leading to diversification of forms. While mechanisms are not independent of each other, I review some of the evidence in support of each. There are a number of directions for future research, including more explicit sampling designs to better address taxonomic richness and for a broader range of taxa. It will be interesting to find ways to partition the relative importance of different mechanisms in contributing to the high variation in diversity among headwaters. The importance of headwater streams to global biodiversity conservation is clear, but will be more evident when better assessments of these small systems are available.

Article
Biology and Life Sciences
Ecology, Evolution, Behavior and Systematics

Dylan J. McNay

,

Christopher Finley

,

Adrian A. Vasquez

,

Xiangmin Zhang

,

Yousra Zouani

,

Jeffrey L. Ram

Abstract: Vernal ponds are temporary, isolated bodies of water that lack vertebrate predators like fish. Palmer Park in Detroit MI USA, contains an old-growth forest with multiple vernal ponds that are home to numerous invertebrates, including water mites, which are the main focus of this study. These vernal ponds are unique since they are geographically isolated in the middle of an urban landscape. Previous research discovered new species of non-biting midges in Palmer Park vernal ponds, suggesting the potential for the discovery of previously undocumented organisms and relationships in this ecosystem. Here we document the invertebrate species found in the vernal ponds of Palmer Park, both to illustrate their diversity and to determine their cytochrome oxidase I barcodes. The barcodes are used in this study to verify identification and to provide reference sequences for comparison to sequences in the diets of water mites also collected from the ponds. Three taxa of water mites found in Palmer Park Pond A are Hydryphantes waynensis, Parathyas sp., and Hydryphantes sp. (distinct from H. waynensis by having a COI barcode 11.6% different from Hydryphantes sp.). This paper also uses Next Generation Sequencing (NGS) to analyze the complex diets of the water mites at Palmer Park. The diets consisted of a diversity of species of worms, mosquitoes, non-biting midges, crustaceans, flies, and beetles. Beetles identified as whole organisms in the ponds or from diet-detected bar codes in vernal pond water mites include Copelatus glyphicus, Acilius sp., and Hygrotus sayi. The diets of water mite in these vernal ponds are compared to previous molecular studies in which water mites in a riverine lagoon were identified as opportunistic predators of a diverse invertebrate diet. Beetles have not previously been reported in water mite diets, so this finding represents a new discovery. Diet analysis revealed taxa and novel barcodes not observed through traditional sampling, highlighting the value of water mites for community characterization. These results support the hypothesis that water mites are opportunistic predators, uniquely reports beetles in their diets, and emphasizes their ecological importance and utility in assessing vernal pond biodiversity.

Article
Biology and Life Sciences
Ecology, Evolution, Behavior and Systematics

George H. Scott

Abstract: Valuably, the International Code of Zoological Nomenclature provides, under its principle of priority, that a species name that has been declared a synonym of an earlier proposed species remains contestable and open to future research. However, as the Code is concerned with namenclature and not with taxonomic concepts, it places no restrictions on declarations of synonymy, enabling them to be published without supporting evidence. This freedom, which is at the core of the synonymy problem contributes to taxonomic inflation and constrains estimates of diversity. From a theoretical perspective, evidence in an unsupported declaration devolves to that of one specimen, the holotype. Furthermore, in the absence of other evidence, the declaration further devolves to one of opinion, with readers left to judge its value based on their knowledge of the declarator. This approach, based on typification, is contrasted with one in which a species exists independently of our perception and is viewable as samples of its local populations. Rather than an arbiter of usage, the holotype then acts only as a referent to its local source population, whose properties define much of the species concept. A worked example of these concepts using data from the planktonic Foraminifera supports the view that evidence of synonymy lies in the source populations of the holotypes.

Article
Biology and Life Sciences
Ecology, Evolution, Behavior and Systematics

Douglas Roy

Abstract: Kin-Selection has traditionally been viewed as a stabilizing force explaining when, and to what degree it can be adaptive for benefits to be shifted among relatives. As such, it is not usually considered a potential accelerant of evolutionary change. Yet benefits conferred on relatives — particularly from parents to offspring — may function more as forward-looking investments than simple transfers. When seen in this light, Kin-Selection emerges as a potential catalyst for rapid phenotypic change. Drawing on concepts from both evolutionary biology and economics, this article introduces the concept of “fitness capital”— traits enhanced by altruistic investment that increase an individual’s capacity to acquire resources for further investment — and shows how overlapping generations and assortative mating can generate cascading, multigenerational effects. These dynamics amplify correlations between parental altruism, offspring ability, lineage-level investment, and traits reflecting fitness capital, creating conditions for runaway increases in both altruism and capacity to invest. By recasting kin-directed altruism as a driver of cumulative social and evolutionary change, the proposed synthesis highlights a novel pathway through which populations may evolve greater investment, social complexity, and phenotypic stratification. It also indicates new perspectives on parent-offspring conflict, costly signalling, sexual selection, and Green-Beard effects.

Article
Biology and Life Sciences
Ecology, Evolution, Behavior and Systematics

Hugo Orlando Paredes Rodríguez

,

Wilfredo Franco

,

Elio Sanoja

Abstract: The Neotropical genus Inga (Fabaceae) is a dominant component of tropical forests and plays important ecological and functional roles; however, its diversity patterns and environmental controls across Andean landscapes remain poorly documented under increasing deforestation pressure. This study quantified the diversity, distribution, and environmental determinants of Inga species in the Imbabura Province, northern Ecuador, by integrating field surveys along five elevational transects, herbarium records, and Geographic Information Systems (GIS)-based analyses of climatic and edaphic variables. We recorded 17 species, nearly tripling previous regional findings. Species richness and occurrence were strongly structured by altitude, temperature, and soil properties. Ten species showed narrow altitudinal range and limited thermal tolerance (<2 °C), indicating habitat specialization, whereas I. densiflora and I. insignis exhibited broader niche breadths and generalist behavior. Edaphically, most species were associated with sandy loam soils, particularly Mollisols and Inceptisols. These results indicate that environmental gradients and soil conditions act as primary filters shaping Inga assemblages in heterogeneous montane landscapes. The high level of specialization observed suggests elevated vulnerability to land-use change and highlights the need for habitat-specific conservation strategies in Andean forests.

Article
Biology and Life Sciences
Ecology, Evolution, Behavior and Systematics

Dominique McCowan

Abstract:

Ecological vulnerability of coral reefs contrasts sharply with their persistence through geologic time, creating a paradox from mis-scaled assumptions of time, mortality and organismal dimensionality, namely bleaching susceptibility, mortality, and recovery are treated as linear or sequential outcomes. Recursive definitions built on such mis-scaled assumptions generate straw-man inferences by conflating vulnerability with fragility and obscuring cryptic recovery dynamics. Using post hoc meta-analyses integrating datasets on coral bleaching, life history, reproductive strategy, morphology, and taxonomy, I evaluate system behavior across matrixed categories of thermal exposure and observation timing. Susceptibility emerges as a graded physiological response with weak coupling between predictor importance and variance, whereas mortality exhibits thresholded dynamics consistent with collapse behavior. Partial overlap in predictor structure indicates that bleaching does not represent a direct trajectory toward death, but rather a regulated buffering phase preceding potential tissue-level failure. Skeletal architecture consistently appears as a strong predictor across susceptibility and mortality, while taxonomic identity shows weak and variable effects. Recovery dynamics further indicate host–symbiont restructuring consistent with recursive evolutionary filtering rather than deterministic trait replacement. Together, these findings reframe coral bleaching as a regulated physiological state decoupled from mortality and demonstrate how recursive logic frameworks resolve paradoxes of timing, scale, and resilience in coral bleaching dynamics.

Article
Biology and Life Sciences
Ecology, Evolution, Behavior and Systematics

Jorge Homero Rodríguez-Castro

,

Sandra Edith Olmeda de la Fuente

,

Jorge Alejandro Rodríguez-Olmeda

,

Ulises de Jesús Balderas Mancilla

,

Juventino Tovar Ortíz

,

José Antonio Rangel Lucio

,

Luis Antonio Vázquez-Ochoa

Abstract: Artisanal fisheries in Mexico frequently operate under data-limited conditions, lacking historical time series of catch and effort. The Atlantic sharpnose shark (Rhizoprionodon terraenovae) is caught by artisanal fisheries in Marine Priority Regions 45-46 and the influence area of the Playa Tortuguera Rancho Nuevo Wetland of International Importance, Tamaulipas, where it acts as a natural predator of Kemp's ridley sea turtle (Lepidochelys kempii) hatchlings, a critically endangered species. In this data-limited context, the population status of R. terraenovae was assessed for the first time using length-frequency based methods. Between November 2018 and February 2020, 541 organisms from the artisanal fishery in La Barra del Tordo were analyzed using FISAT II. The von Bertalanffy growth parameters for combined sexes were: L∞ = 105 cm, k = 0.59 yr⁻¹, t₀ = -0.195 yr. Total (Z), natural (M), and fishing (F) mortality rates were 4.13, 0.467, and 3.22 yr⁻¹, respectively. The mean exploitation rate (E = F/Z) was 0.78 (95% CI: 0.745-0.805), exceeding the reference point of 0.5 (Gulland, 1971), indicating severe overexploitation. The parameters showed biological consistency (Ø' = 3.81; M/k = 0.79), and natural mortality (0.467 yr⁻¹) fell within the range reported for the species. This finding, in a priority conservation region under the Conservation Sector regime of the Marine Ecological Zoning Program, evidences the urgent need to implement ecosystem-based fisheries management. The study demonstrates that, even with limited data, it is possible to obtain robust estimates that reconcile fisheries sustainability with L. kempii conservation in protected natural areas.

Article
Biology and Life Sciences
Ecology, Evolution, Behavior and Systematics

Douglas Roy

Abstract: An influential intuition about the biology of aging is that organisms are born with a fixed amount of “life stuff” that they burn through in the process of living. According to this mindset, the key to living longer is simply to burn through this life stuff as slowly as possible. We instead reinterpret this “life stuff” as Survival Capital: resources allocated to maintenance and growth that can compound over time to facilitate future reproduction. Contrasting with classical evolutionary theories that treat life-history expenditures as linear substitutes, we develop an explicit framework in which investments in survival and reproduction act as synergistic complements. We first show how early-life investments in survival traits generate complementary incentives for later-life investments, thereby increasing the value of survival into older ages. We then add multiplicative damage to survival, capturing biologically plausible risk accumulation without altering the qualitative logic of the first model, thereby reinforcing the effects of complementarity among survival investments. Next, we demonstrate that such complementarities naturally imply bi-stability of life-history strategies when trade-offs between survival and reproduction across discrete life stages are considered. Finally, we show that when investments can be made to affect multiple components of health and interact synergistically, they can produce runaway increases in health investment, driving extreme healthspans. This moves beyond the classical “fast–slow” continuum by making the value of later life endogenous. Linking these allocation trade-offs to existing evidence concerning real world counterparts of Survival Capital generates powerful empirical predictions for both evolutionary biology and synergistic geroscience.

Review
Biology and Life Sciences
Ecology, Evolution, Behavior and Systematics

Ping Xie

Abstract: The origin of eukaryotes represents one of the most profound unresolved questions in evolutionary biology. Although more than a dozen competing hypotheses have been put forward, no unified consensus has yet been reached. This paper critically reviews the major endosymbiotic and non-endosymbiotic theories, revealing a critical limitation shared by most existing models: the nearly 2.5-order-of-magnitude difference in genome size between prokaryotes and eukaryotes cannot be sufficiently explained by stochastic endosymbiotic events alone. I propose a new integrative framework in which eukaryogenesis is viewed as a process of subcellular structuralization driven primarily by DNA packing. This framework reconciles contradictions in current theories by clarifying the dynamic coupling between genome expansion induced by rising atmospheric oxygen and the emergence of sophisticated DNA packing mechanisms, which together supported the increase in cellular complexity, genome enlargement, and ordered biochemical processes. This study seeks to resolve long-standing controversies among competing paradigms, establish a robust theoretical framework for reconstructing eukaryogenesis, and provide critical direction for future interdisciplinary investigations.

Article
Biology and Life Sciences
Ecology, Evolution, Behavior and Systematics

David C. Richards

,

Richard Mickelsen

,

Gustavious P. Williams

,

Brett Marshall

,

Sam Rushforth

,

Sarah J. Rushforth

Abstract: Light limitation constrains ecosystem function in large, shallow eutrophic lakes, yet the ecosystem-scale role of sediment resuspension is rarely isolated. We quantified wave- and bioturbation-driven resuspension effects on light attenuation in Utah Lake using repli-cated limnocorrals (~12 m diameter; 1.2–2.4 m depth) deployed over three growing seasons (2022–2024). Secchi depth (n = 363) and PAR profiles (7 depths; n = 126) were measured inside corrals and at paired open-lake controls. Mean Secchi depth was nearly twofold greater inside corrals (39.8 vs. 22.0 cm; p < 0.001), with lower light attenuation coefficients (k = 0.17 vs. 0.22). Ln(PAR) depth regressions consistently showed weaker attenuation under reduced disturbance, producing compensation depths 1.25× deeper inside corrals. Although near-surface PAR was sometimes higher in the open lake, PAR below 0.5 m was consistently greater inside corrals. Reduced attenuation was linked primarily to lower suspended solids and decreased resuspension of fine sediments and CaCO₃ precipitates; phytoplankton biomass further influenced late-summer attenuation. Sediment resuspension thus dominates underwater light climate, constrains benthic production, and reinforces phytoplankton-dominated pathways. Stabilizing sediments through invasive carp removal, macrophyte and mollusk recovery, and reduced dis-turbance should enhance light availability, benthic–pelagic coupling, and ecosystem function in turbid shallow lakes.

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