Ecology Of Species Research Articles

The monocled cobra (Naja kaouthia Lesson, 1831) is a medically important elapid snake with substantial geographic variation across South and Southeast Asia. Throughout its broad distribution, spanning various major ecoregions and habitat types, N. kaouthia displays a great amount of phenotypic variation. Recent taxonomic developments in the Asiatic cobras (Naja, subgenus Naja), namely the description of a new species (Naja fuxi Shi et al. 2022), have resulted in confusion regarding the affinities of non-spitting cobras across Indochina. Due to close morphological resemblances and poorly resolved phylogenetic relationships among three sympatric and/or parapatric taxa (N. atra, N. fuxi, and N. kaouthia), additional research is needed to disentangle species limits, evolutionary history, ecology, and distribution of these species from one another. A long history of taxonomic confusion and ambiguity in this group, combined with the suggestion of additional cryptic and unrecognized diversity, underscores a need for continued study of the Asiatic cobras. Consequently, we summarize information on N. kaouthia, compiling data on geographic distribution, phylogenetic relationships, phenotypic variation, venom variation, and venom spitting behavior. While distribution-wide trends do appear to be present for some characteristics (i.e., regional trends in venom spitting behavior, body coloring and patterns), they are apparently lacking or poorly defined for others (i.e., trends in venom composition). In view of future study on N. kaouthia, and accounting for the missing holotype, we designate a neotype for the species, thereby restricting the type locality to 24 Parganas, West Bengal, India, within the original ambiguous type locality of “Bengale, Inde”. Future taxonomic treatments resulting in the recognition of additional diversity within N. kaouthia will thus require that the name be maintained for snakes from the newly restricted type locality. We encourage detailed investigation on the Asiatic cobras using integrative lines of evidence combining mitochondrial, nuclear, and morphological datasets, but emphasize that nomenclatural decisions should only be made with a large body of supporting evidence.

ABSTRACT Native to South America, moth plant (Araujia hortorum, Apocynaceae) is an invasive vine that threatens natural ecosystems and agriculture in many parts of the world. Biological control studies involving fungal pathogens have primarily focused on the rust Puccinia araujiae, but other aggressive pathogens exist that may show potential as complementary agents. In its native range in Argentina, plants were quite frequently observed with severe leaf and fruit damage caused by a fungal disease. The pathogen associated with this disease was isolated and identified as Septoria araujiae based on morphological analyses. Multilocus analyses allowed the first phylogenetic placement of this species within the genus. Koch’s postulates were fulfilled through inoculation experiments, confirming S. araujiae as the causal agent. The pathogen exhibited a hemibiotrophic life cycle, with an extended asymptomatic phase followed by a necrotrophic stage that led to severe defoliation. Host specificity experiments revealed a narrow host range, with susceptibility largely confined to species within the subtribe Oxypetalinae. These findings contribute new insights into the diversity, ecology, and host interactions of Septoria species and highlight the potential of S. araujiae as a biological control agent for A. hortorum.

The aquatic biodiversity of the Amazon basin is heavily influenced by environmental factors, such as altitude, rainfall cycles, and dry seasons. These factors impact the water's physical and chemical parameters, consequently affecting the distribution and diversity of fish. The order Siluriformes Cuvier, 1817, particularly the family Pimelodidae Bonaparte, 1835, is ecologically and economically significant due to its migratory behavior and dependence on the region's water variability. The genus Brachyplatystoma Bleeker, 1862 includes species of high commercial value, such as “dourada” Brachyplatystoma rousseauxii (Castelnau, 1855) and “piramutaba” Brachyplatystoma vaillantii (Valenciennes, 1840) and is fundamental to fishing in the Amazon. This study provides a thorough review of the taxonomy, ecology, migration, and genetic diversity of species in this genus. Information was collected from scientific articles, theses, and books using databases such as Scholar Google, SciELO, Scopus, Web of Science, WoRMS, Consensus, and INPA databases. The results underscore the significance of morphological and ecological adaptations in response to the seasonal dynamics of Amazonian rivers. Additionally, eco-morphological analyses reveal essential information about habitat use, resource sharing, and evolutionary patterns shaped by environmental pressures and phylogenetic constraints. These data are essential for developing sustainable fisheries management strategies and conserving aquatic biodiversity in the Amazon.

Features of the ecology of the sibling species M. (T.) majori and M. (T.) daghestanicus in some places of their contact on the Greater and Lesser Caucasus were studied. An analysis of symbiotopic samples of the sibling species from two localities in the Karachay-Cherkessia (the right bank of the Kizgich River and the vicinity of the village of Verkhny Arkhyz) and a mixed sample from the sympatry zone in the vicinity of the village Ankavan in Armenia was made. The obtained priority data make it possible to assert that an important condition for the coexistence of the sibling species M. (T.) majori and M. (T.) daghestanicus is their separation by residence stations, as well as by a number of environmental features. It has been shown that differences in the peculiarities of the population structure (age and sex composition), as well as in the reproduction strategy, allow the sibling species of the Caucasian pine voles to coexist in places of their contact, even under symbiotopy conditions. The previously known craniometric features, confirming differences between the sibling species of the Caucasian pine voles in food specializations, which may also be one of the factors ensuring their coexistence at the places of contact, are discussed.

Understanding how ecological and evolutionary forces shape biodiversity is a core pursuit in macroevolutionary research. Species' dispersal ability significantly impacts their colonization chances and geographic isolation, profoundly influencing species ecology and evolution. Our study delved into the relationship between dispersal ability and speciation rates within Emberizoidea, a diverse group of passerine birds. We used the Hand-Wing Index (HWI) as a morphological proxy for dispersal ability and phylogenetic data for 749 species of Emberizoidea (∼90% of all recognized species for the clade) using trait-dependent diversification models, including continuous-state (QuaSSE) and hidden-states (SecSSE) models. We also applied the Correlated Speciation and Trait Rates Simulation (Cor-STRATES) framework to assess correlation between HWI evolution and speciation rates. Our findings revealed that speciation in Emberizoidea was not significantly influenced by dispersal ability as estimated by HWI. While QuaSSE models suggested a peak in speciation rates at intermediate HWI values, the best-fit SecSSE model indicated that speciation was driven by unmeasured trait(s) rather than HWI. Moreover, HWI evolution and speciation rates were not correlated, suggesting that wing shape evolution is unrelated to cladogenetic events in Emberizoidea's evolutionary history. Our study challenges the notion that dispersal ability and wing shape drive diversification in birds, particularly in Emberizoidea.

Amphioxus, a key model organism in vertebrate evolution, is essential for understanding ecological balance and species diversity. This study examined the spatiotemporal distribution of Branchiostoma japonicum and assessed its habitat suitability in the Changli Golden Coast Nature Reserve and adjacent coastal waters from 2008 to 2023 (excluding 2020). The maximum abundance showed marked fluctuations, with a sharp decline between 2008 and 2015 followed by recovery after 2016, reaching a peak of 345 ind./m2 in 2022. The average abundance also increased, peaking at 34 ind./m2 in 2022. Spatially, the higher abundances occurred in central stations, while peripheral sites were much lower, sometimes absent. Spearman’s correlation and Principal Component Analysis (PCA) identified sediment grain size (1~0.25 mm), water depth and sediment sulfide as key environmental factors. A habitat suitability index (HSI), constructed using the Analytic Hierarchy Process (AHP), showed higher values in central stations, indicating more favorable conditions. These findings highlight the importance of long-term monitoring, clarify the ecological requirements of amphioxus, and provide guidance for habitat conservation and management in regions affected by environmental change and human activities.

Deforestation, habitat loss, and fragmentation impact the ecology, genetics, and health of many wildlife species, including primate populations. We evaluated the association between landscape characteristics and demographic features of Alouatta caraya howler monkeys in human-modified rural areas of Pampa del Indio in the Argentine humid Chaco. Landscape metrics were obtained from a supervised classification of a Landsat 8 image based on different kinds of exploited forests. Four times over a 2-year period, we surveyed howler monkey groups using loud calls heard at 113 listening posts in three habitat types: gallery woodland, riparian, and quebrachal hardwood forests. We also determined the age and sex composition of 31 groups through observation. A Bayesian spatial generalized linear mixed model using Integrated Nested Laplace Approximation with a Stochastic Partial Differential Equation to account for spatial dependence revealed a negative association between howler monkey group counts and prime habitat availability (i.e., old-growth forest). Howler group size was positively associated with patch density, while both the immature-to-adult female ratio and group size were negatively associated with the division index of prime habitat. Despite the apparent ability of howler monkeys to cope with habitat modification, prime habitat availability is crucial to the long-term conservation of A. caraya. Innovative landscape management strategies are required to ensure the long-term persistence of howler monkeys in human-modified environments under rapid change in the Gran Chaco eco-region.

The absorption, immobilization, and response mechanism of Leymus chinensis to microplastics and nanoplastics.

Abstract Numerous traits that define behaviour, development, life‐history and species ecology are expressed as dichotomous alternative phenotypes (e.g. morphological and behavioural polyphenisms, reproductive vs. non‐reproductive states, movement vs. philopatry). Accordingly, core objectives spanning behaviour, demography and evolutionary ecology are to decompose phenotypic variation in dichotomous traits into different environmental and/or genetic components, and thereby infer biological mechanisms and predict future dynamics. However, perhaps surprisingly, variance decompositions for dichotomous phenotypes have not been rigorously defined or comprehensively achieved. While analysts commonly use generalised linear mixed models (GLMMs) to estimate variance components on underlying, latent continuously distributed scales, conceptual and mathematical formalisations of back‐transformations onto the dichotomous scale of phenotypic expression have been lacking. These methodological limitations hinder full conceptualisation and evaluation of biological processes and impede cross‐system comparisons, but such challenges are rarely acknowledged. Accordingly, we first synthesise current approaches to modelling dichotomous phenotypic variation. Using the threshold model paradigm, we clarify the meaning of latent‐scale GLMM parameters. We then formulate and solve exact back‐transformation equations, linking the continuous latent scale (termed ‘liability’) to the dichotomous phenotypic scale. We use these derivations to devise a new methodology to systematically define and quantify all components of phenotypic variance that non‐linearly emerge from linear combinations of latent liability‐scale effects. We thereby provide an easy‐to‐implement calculation procedure (and R codes) for fully and accurately decomposing phenotypic variance in dichotomous traits using GLMM estimates. We highlight three main applications, with worked examples, to show how our novel back‐transformation methodology can address three core challenges in ecology and evolutionary biology: validly quantifying repeatability in binary behaviours, heterogeneity in individual contributions to population growth and genetic variances in dichotomous phenotypes. These applications illustrate how our full variance decompositions systematically quantify individual and/or genetic differences in phenotypic plasticity, revealing critical eco‐evolutionary processes. Overall, we provide new capability to comprehensively quantify and rationalise emerging variation in dichotomous phenotypic traits. By revealing key biological properties that were previously hidden and eliminating inaccuracies and misconceptions that are otherwise likely to be commonplace, we open broad opportunities to meaningfully dissect dichotomous phenotypic variation in ecological and evolutionary research.

The genus Liriomyza Mik (Diptera: Agromyzidae) comprises a diverse group of leaf-mining flies that feed internally on plant tissues, with species ranging from host plant specialists to highly polyphagous pests. In this genus, Liriomyza trifolii, Liriomyza sativae, and Liriomyza huidobrensis have emerged as the dominant invasive species in China over the past three decades, causing extensive damage and complicating pest management efforts. Owing to having overlapping host ranges, these species frequently co-occur, resulting in intense interspecific competition and, in many cases, competitive displacement. This review synthesizes recent advances in understanding the invasion dynamics, species displacement processes, and ecological interactions of these three species. We highlight how interspecific competition, driven by variation in host preference, insecticide resistance, and climatic adaptability, has shaped species distributions and displacement outcomes. We also examine cryptic diversity within species, the importance of accurate diagnostics, and the limitations of current quarantine and management strategies. Finally, we discuss promising directions for integrated pest management, including the development of host plant resistance, the deployment of novel insecticides, and the application of molecular tools. By positioning Liriomyza as a model system, this review contributes to a broader understanding of invasive species ecology and offers guidance for the sustainable management of leafminers and other invasive agricultural pests.

In the dynamic and increasingly threatened marine environment, understanding the full spatial ecology of species like the reef manta ray (Mobula alfredi) is crucial for effective conservation. While typically considered a shallow-water species, reef manta rays in New Caledonia were investigated to explore their vertical habitat use. This study utilized satellite telemetry data from 19 tagged individuals, with three tags providing sufficiently high-resolution information on dive behaviour, to describe and quantify three-dimensional movements. We found that New Caledonian reef manta rays exhibit outstanding deep-diving capabilities, with all individuals diving below 300 m and one reaching 672 m. These deep dives occurred regularly, averaging one every 4.8 days, which is notably more frequent than in other studied populations. Dive profile analysis revealed a mixture of foraging and exploratory behaviors, supporting the hypothesis that these deep excursions are driven by the search for demersal or mesopelagic food resources. Our findings highlight the ecological plasticity of M. alfredi and demonstrate that their habitat use extends far beyond the coastal, shallow waters previously assumed, a critical consideration for developing comprehensive and effective marine protected areas.

ABSTRACTTemperate waters, such as the Great Lakes, are predicted to increase in temperature by 1°C every decade. Many poikilothermic fish thermoregulate behaviourally, moving to more suitable thermal environments. Embryos are incapable of locomotion and may be exposed to non-optimal temperatures during development. Previous work has suggested that temperature increases during embryogenesis can alter growth rates in fish. However, less is known of whether these early-life exposures to elevated temperatures can impart alterations to the phenotypic plasticity of performance traits, particularly in temperate species. We hypothesized that increased embryonic incubation temperature would diminish the larval performance of yellow perch (Perca flavescens), a critical cultural and ecological species of fish. We reared yellow perch embryos at 12, 15 or 18°C until hatching; after hatching, the temperature was raised to a common garden 18°C, their preferred post-hatch temperature. We assessed exploratory behaviour, metabolism (oxygen consumption) and cardiac performance throughout early development. At hatch, 12°C fish exhibited the greatest swimming activity, with 18°C fish consuming the least oxygen and possibly experiencing mitochondrial dysfunction. Cardiac development was more advanced at hatch in 18°C fish. Yet, warmer incubated fish had diminished movement and increased oxygen consumption at 20 days post-hatch, demonstrating long-term disruptions of increased temperature in the embryonic environment. Overall, elevations in rearing temperature may cause metabolic dysfunction and behavioural alterations, potentially impacting the survival of yellow perch.

Body size variation in vertebrates is a complex polygenic trait, tightly correlated with numerous aspects of a species' biology, ecology, and physiology. Miniaturization, the extreme reduction of adult body size, is a common phenomenon across the Tree of Life, yet the mechanisms underlying this process are poorly understood. Here, we investigate the molecular basis of body size evolution in goby fishes, a clade encompassing some of the smallest vertebrates on Earth. We generate a genome-wide phylogeny for 162 Gobioidei species and perform comparative transcriptomics across three clades with repeated instances of miniaturization and large-bodied forms. We identified 54 differentially expressed one-to-one orthologs between miniature and large-bodied species. These genes reveal distinct functional profiles, suggesting that regulation of cell numbers is a key mechanism governing body size control. Miniature species consistently overexpress growth inhibitors like CDKN1B and ING2, associated with tighter cell cycle regulation and decreased proliferation rates, while large-bodied species upregulate growth-promoting genes such as TGFB3, linked to tissue development and growth signaling. These enriched functional pathways, conserved since the Eocene (50 Ma), suggest macroevolutionary convergence in size regulation over deep time. Our findings provide insights into how size determination is governed at a genetic level and highlights the importance of exploring these factors in nonmodel organisms to uncover the fundamental processes regulating vertebrate body size evolution.

Across the Cascadia bioregion, salmon and steelhead are ecological and cultural keystone species that contribute to and illustrate riverine health. Due to complex social, economic, and ecological relations over the past 150 years, many Columbia River Basin salmon and steelhead populations are now listed as threatened or endangered in the United States. This research uses the 2017–2020 Columbia Basin Partnership Task Force as a case study to understand how this collaborative governance effort of sovereign entities and nonsovereign stakeholders navigated competing water claims to reach consensus on aspirational qualitative and quantitative goals for salmon and steelhead restoration. Using semistructured interviews and a review of meeting minutes, reports, and other documents produced by the group, we found that parts of the collaborative process, in particular the pairing of Indigenous knowledge and science with Western science for decision-making, unsettled long-standing territorial claims and changed the span and durability of hydrosocial networks in the Columbia River Basin.

Adaptation to different environments is thought to play a key role in speciation. However, speciation typically begins in allopatry, where reproductive isolation can also arise through neutral processes or selection unrelated to ecological differences. Disentangling the role of adaptive ecological divergence in the early stages of speciation therefore remains an important challenge in understanding the origin of new species. Here, we study threespine stickleback populations that have recently evolved in isolated postglacial lakes either in the presence or absence of prickly sculpin-a resource competitor that also shares ubiquitous trout predators with stickleback. We simulated secondary contact between several stickleback populations from these two ecological contexts in large, seminatural ponds, and genotyped offspring from 411 mating events to assess the strength of premating isolation associated with this biotic factor. Assortative mating between populations of the same ecological type (i.e., both sculpin-sympatric or both solitary) was moderate on average but ranged from weak to complete. Strikingly, and in line with a central premise of ecological speciation, the strength of premating isolation increased with increasing morphological and genomic population divergence shaped by sculpin-mediated selection. In contrast, overall phenotypic and genomic population divergence agnostic to sculpin presence/absence only poorly explained premating isolation, highlighting how ecological speciation in allopatry can be obscured by other sources of divergence. More broadly, our findings demonstrate how interactions with other ecologically similar species can play a major role in initiating and driving evolutionary trajectories toward new species, even in allopatry.

Abstract IntroductionFreshwater fauna are increasingly threatened by habitat degradation and climate change. Rising flood frequency and magnitude underscore the need for river restoration to enhance ecosystem resilience. While restoration is widely promoted, outcomes for freshwater fish remain inconsistent. Success depends heavily on restoration design, water quality, and bio‐indication tools. Yet, many studies lack an approach that considers fish demographics, assemblages, and habitat characteristics simultaneously.ObjectivesThis study assessed the effectiveness of remeandering designs on fish communities at both the river and reach scale. We evaluated ecological outcomes using multiple metrics, including the ecological quality ratio (EQR), species composition, demographics, life‐history traits, and environmental drivers.MethodsFish and environmental data were collected in restored and control reaches over 4 years post‐restoration and compared with historical reference data. We evaluated spatial and temporal trends and assessed how specific restoration designs influenced fish metrics.ResultsFive years post‐restoration, no significant river‐scale improvements in EQR were observed. However, several restored reaches showed clear local improvements. A positive trend over time highlights gradual ecological recovery and reflects the disruptive effect of a flash flood 1 year post‐restoration. The reach with a more complex restoration design exhibited higher juvenile abundance, broader reproductive guild diversity, and more complete age‐class structures.ConclusionsWhile river‐scale improvements were limited, reach‐scale results demonstrated that restoration design is crucial in driving fish recovery. Habitat diversity, conceived through in‐stream adaptations, emerged as a key factor for success.

With the advancement of agriculture, deforestation for farmland has disrupted ecological balance and species patterns. This study constructs multiple models for analysis: the Basic Farmland Ecosystem Model (BFW) established based on the Lotka-Volterra competition model, and the Marginal Species Regression model (MSR) that combines improved cellular automata with the LV model. Results demonstrate that the return of marginal species enhances system stability. The impacts of reducing pesticide application and introducing bats are also investigated. An Eco-Sustainability Indicator (ESI) is developed to optimize organic farming models, identifying the optimal parameter combination. Specifically, a 0.5 increase in the fertilizer factor and a 20% increase in secondary-consumer biomass yield the maximum ESI of 0.7098. This research provides theoretical foundations and model support for the sustainable development of agro-ecosystems, integrating ecological dynamics and human intervention strategies through interdisciplinary modeling approaches.

Halyomorpha halys (Stål), an invasive species of Asian origin, has become a key pest of tree fruit in areas of the Eastern and Pacific Northwest United States. This study used a 5-yr dataset of pheromone trap captures from 4 ecoregions (Mountains, Piedmont, Southeastern Plains, and Atlantic Coastal Plain) of North Carolina to validate temperature-driven phenology models previously reported for oviposition by overwintering adults and eclosion of F1 adults using semi-field cage studies. Cumulative proportion of pheromone trap captures of F1 adults and nymphs over cumulative degree days was compared to predictions based on the previously reported models' quadratic equation curves for adult eclosion (y = -0.0000015x2 + 0.004736x - 2.664) and oviposition (y = 0.0000032x2 - 0.010853x + 9.050). The oviposition model was validated using projected oviposition curves to predict nymphal populations over time by using life stage-specific development and mortality rates. Analysis of coefficients of determination (R2) for all regressions showed that F1 adult model predictions varied by region and year. Mean R2 values in the Mountain, Piedmont, and Southeastern Plains ecoregions for F1 adults were 0.88, 0.93, and 0.93, respectively. Nymphal regressions also varied by ecoregion, with mean R2 values of 0.95, 0.86, and 0.88 in the Mountains, Piedmont, and Southeastern Plains, respectively. Differences among regions were mostly associated with lower R2 values at sites with low population densities. Results are discussed in relation to the value of these models in studying the ecology of invasive species and in informing pest management decisions.

A trade-off between aquatic and terrestrial locomotion is self-evident at broad phylogenetic scales. While the effects of more subtle trade-offs in the evolution of closely related species are less clear, they are hypothesized to drive ecological speciation and adaptive radiation. Amphibious animals strike a balance between aquatic and terrestrial activity, and the need to maintain performance in one medium is hypothesized to constrain evolution of high performance in the other (the running-swimming dilemma). Closely related species of Desmognathus salamanders partition local habitats along a gradient from mid-stream to stream edge to completely terrestrial. The trade-off hypothesis predicts that these species will differ in relative running vs. swimming performance depending on the relative importance of each mode of locomotion in their niches. Here, I show that primarily aquatic Desmognathus ecomorphs are superior swimmers and inferior runners relative to semi-aquatic ecomorphs using paired escape performance trials in aquatic and terrestrial arenas. I measured performance as the velocity of the fast-start response to simulated predator attack. I tested two species of each ecomorph, representing two divergent clades with parallel evolution of aquatic and semi-aquatic species. Notably, the different southern clade ecomorphs have been genetically isolated for millions of years, whereas the northern clade ecomorphs share a recent common ancestor and interbreed regularly. My results showed a negative correlation between aquatic and terrestrial performance, with aquatic ecomorphs being faster swimmers and semi-aquatic ecomorphs being faster runners. While there was a possible trend consistent with faster swimming speeds of northern forms relative to their southern counterparts, the functional differences between ecomorphs were similar in both clades. These results are consistent with the hypothesis that trade-offs between aquatic and terrestrial locomotion have contributed to a consistent pattern of habitat partitioning during parallel speciation.

This presentation outlines the development, process and aims of the Botanic Laboratory Garden [Bot] [Lab] at Royal Central School of Speech and Drama. This performance and space for research hosts an ongoing programme of curated research projects exploring the relationship between the ecology of urban land use, landscape(ing), well-being spaces and plant species specifically grown for use and harvest in scenographic and performance practice – dyes, pigments, textiles, scent and sound. I will focus on the slipperiness of plant species and the crossing of borders with what Jessica J. Lee describes as “out of place” species. This is defined through Latin taxonomy and how we can explore migration of plants as “native” and “invasive” species within a shifting global migration, geopolitical boundaries and environmental climate. I argue this curatorial approach operates in an open dramaturgical form, rather than a fixed and completed architectural space, with porous borders - a fluid and shifting programme of performance research, navigating the integration of botany, edaphology and scenography of landscape. The transience or ephemerality of scenography in a botanic laboratory, in its very nature as a research centre, can challenge intentions of landscaping and cultivation as a colonial, constructivist human intervention.