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Genetic polymorphism of alien species in their secondary ranges is an important evidence of invasive process course. In this paper, we studied a molecular genetic variation of Lupinus polyphyllus Lindl. at geographically extensive material from different parts of its secondary distribution range at East European Plain and a contribution of L. polyphyllus to natural vegetation there. Genetic variation was studied on nuclear ribosomal internal transcribed spacer sequences ITS1–2, chloroplast intergenic spacer rpl32–trnL sequences, and on inter-simple sequence repeat (ISSR) markers. ITS1–2 sequences were non-informative markers of intra-species variability for L. polyphyllus . In the phylogenetic tree on the base of chloroplast rpl32–trnL sequences no geographical trend was revealed among and within the three major clades and subclades but sufficient level of intra-population variability was detected. ISSR sequences of 38 individuals demonstrated statistically significant among-individual variation both within local populations and among local populations. The latter was the only significant factor of sample differentiation in the reduced ordination space at two spatial scales: among the local populations (ANOSIM test, R = 0.33, p  < 0.01) as well as among the enlarged locations consisting of the neighboring populations (R = 0.26, p  < 0.01). All investigated populations of L. polyphyllus at East European Plain invaded anthropogenically disturbed habitats, with present or former settlement activity. The revealed genetic variability of specimens at the lowest spatial scale may be a cue for a high invasion potential of L. polyphyllus in the studied part of the secondary range at ongoing climatic changes.

The common bottlenose dolphin (Tursiops truncatus) is a top marine predator widely dispersed in coastal and pelagic habitats and with a generalist feeding behavior. Yet, information on the trophic ecology of animals inhabiting pelagic environments is still scarce. Using carbon (δ13C: 13C/12C) and nitrogen (δ15N: 15N/14N) stable isotope ratios, we identified and quantified the main groups of prey assimilated by bottlenose dolphins inhabiting an oceanic habitat (Madeira Island, East Atlantic). Bottlenose dolphins assimilated pelagic, schooling fish (such as blue jack mackerel, Trachurus picturatus) and mesopelagic and demersal squids, which reinforces the pelagic dietary composition of insular/oceanic dolphins. Also, intra-seasonal differences were found in their stable isotope ratios, which suggest intraspecific variability in the feeding behavior among individuals living in the same area. Sex was not the main factor contributing to these differences, suggesting the lack of trophic niche segregation between adult males and females in this offshore environment. Nonetheless, further studies including different life stages and information on the ecophysiological requirements are necessary to disclose the factors responsible for the observed variability. This study showed that insular dolphins fed primarily on economically important pelagic prey, highlighting the need of developing management strategies that integrate conservation in fisheries plans.

Intrapopulation variability in growth trajectories among conspecifics provides a reservoir of phenotypic diversity that can buffer populations against environmental change. From a life‐history and metabolic‐scaling perspective, this variability reflects alternative resource‐allocation strategies—ranging from rapid biomass accretion to energy conservation—that may represent bet‐hedging under fluctuating environments. Biochemical metabolic processes may underpin these diverse strategies, though the mechanisms involved remain poorly understood. A cohort of Gammarus insensibilis, a broadly distributed aquatic macroinvertebrate commonly found in transitional water ecosystems, was reared under laboratory conditions for 75 days. Despite being of the same age, individuals displayed marked size differences and were subsequently classified by body size into Small (S), Medium (M), and Large (L) groups as proxies for slow, intermediate, and fast growers. To test the occurrence of a biochemical basis of this intrapopulation variability, a single‐organism 1H NMR metabolomics approach was applied to Gammarus insensibilis individuals. Metabolic profiling of each animal revealed discrete “fingerprints” rather than a uniform baseline state, with at least two major metabolic pathways significantly different between S and L size individuals. These pathways included alanine, aspartate, and glutamate as well as arginine metabolism. Medium‐sized individuals displayed intermediate profiles with unique metabolite ratios pointing to phenotypic plasticity. These results highlight the utility of 1H NMR spectroscopy in resolving individual metabolic states and identifying anabolic pathways linked to growth phenotypes, suggesting that phenotype‐dependent performance under fluctuating conditions may maintain intrapopulation variability. For the first time in Gammarus insensibilis, a single‐organism 1H NMR metabolomics approach was applied to investigate the intrapopulation variability in growth trajectories showing how divergent size classes, despite being of the same age, reflect alternative resource‐allocation strategies.

Phytoplankton dynamics models follow either an Eulerian or a Lagrangian approach. The Eulerian formulation assumes that all individuals of a population living in homogeneous environmental conditions, i.e. within a model grid cell, are in a single average physiological state, which generally depends on local conditions. By tracking each individual cell or cluster of cells, the Lagrangian formulation allows population behaviour to emerge from a broader range of individual physiological states inherited from different life histories. In order to determine in which mixing conditions the widely used Eulerian approach differs from a more representative but also more computationally costly Lagrangian formulation, we compared the results obtained from a simple 1-dimensional phytoplankton growth model using both formulations under various mixing conditions. The chosen model is based on Droop kinetics, where growth is a function of light and an internal nutrient cell quota. It is applied in cases with constant and uniform diffusivity, and in more realistic cases of wind-induced and tidal mixing. The 2 main outcomes of our study are: (1) results from both formulations converge in weakly stratified environments for any level of turbulent mixing, and (2) results diverge in stratified environments and intermediate mixing up to a diffusivity value above which the environment appears homogeneous to moving cells, and both formulations converge. These results suggest that in heterogeneous and dynamic marine environments, strong variability among individuals may prevent Eulerian models from accurately predicting phytoplankton production.

Laternula elliptica is a key bivalve species and widely distributed around the Antarctic continent. This bivalve has been the study subject in several studies centered on ecological, physiological, biochemical, and behavioral patterns. However, little is known about the chemistry and the biomechanical properties of the shells of this mollusk. Here, we present the first report of the intra-population variability in the organic composition and mechanical properties of L. elliptica shells. Further, we analyze different morphological traits and their association with the metabolism of a population of L. elliptica from King George Island, Western Antarctic Peninsula. The summer metabolic rates and the hepatosomatic index values indicate good health conditions of this clam’s population. Shell periostracum chemistry is quite similar to bivalves from temperate regions, but the relative amount of protein increased ca. five-fold in shells of L. elliptica. The microhardness is approximately 32% lower than in bivalves from temperate regions. Our characterization of the L. elliptica shells suggests that periostracum chemistry could be specially fitted to avoid shell carbon exposure to dissolution (e.g., in corrosive acidified seawater). In contrast, the reduction in shell hardness may result from prioritizing behavioral (burial) and shell repairing strategies to confront biological (predators) and physical disturbances (e.g., ice scouring). Similar studies in other Antarctic mollusks will help understand the role of shell structure and function in confronting projected climate changes in the Antarctic ocean.

Phytochemical profiling of six natural populations of Gentianella austriaca was performed by HPLC identification and quantification of a number of secondary metabolites, and evaluation of time series of peak areas by chemometric analysis. Phytochemical analysis of G. austriaca revealed the presence of iridoids, flavone-C-glucosides and xanthones. Twelve secondary metabolites were identified in the aerial parts, roots and seeds, including swertiamarin (SWM), gentiopicrin (GP), sweroside (SWZ), isoorientin (ISOOR), swertisin (SWE), demethylbellidifolin-8-O-glucoside (DMB-8-O-glc), bellidifolin-8-O-glucoside (BDF-8-O-glc), mangiferin (MGF), corymbiferin (CBF), corymbiferin-1-O-glucoside (CBF-1-O-glc), bellidifolin (BDF) and campestroside. Multivariate statistical analyses showed relatively low variability among populations according to secondary metabolite content. However, some pharmacologically important compounds were found in higher amounts in a few populations, which could be useful for conservation and future biotechnological procedures.

Natural populations of Gentiana asclepiadea L., located at two mountainous sites, were HPLC-analyzed regarding the contents of six representative secondary metabolites. The contents of swertiamarin (SWM), gentiopicrin (GP), sweroside (SWZ), mangiferin (MGF), isoorientin (ISOOR), and isovitexin (ISOV) were determined in six populations (three per study site), and separately for aboveground and belowground plant parts. PCA showed a clear separation of four groups according to the contents of the analyzed secondary metabolites. Out of six analyzed compounds, five were present in all samples and only one (SWZ) was found in Golija populations (belowground parts) but not in Vlasina populations, and its presence can be indicative of the geolocation of populations. Clear separation of groups was mostly affected by the different contents of chemical compounds in plant parts (aboveground versus belowground) and by the differences related to population origin (higher content of SWM and GP in belowground parts of individuals from Vlasina populations and higher content of MGF and ISOOR of individuals from Golija populations). The results of this study contribute to the spatiochemical profiling of G. asclepiadea populations and a better understanding of inter- and intrapopulation variability of pharmacologically important compounds.

1. Determining location and timing of ontogenetic shifts in the habitat use of highly migratory species, along with possible intrapopulation variation in these shifts, is essential for understanding mechanisms driving alternate life histories and assessing overall population trends. Measuring variations in multi-year habitat-use patterns is especially difficult for remote oceanic species. 2. To investigate the potential for differential habitat use among migratory marine vertebrates, we measured the naturally occurring stable nitrogen isotope (δ¹⁵N) patterns that differentiate distinct ocean regions to create a 'regional isotope characterization', analysed the δ¹⁵N values from annual bone growth layer rings from dead-stranded animals, and then combined the bone and regional isotope data to track individual animal movement patterns over multiple years. 3. We used humeri from juvenile North Pacific loggerhead turtles (Caretta caretta), animals that undergo long migrations across the North Pacific Ocean (NPO), using multiple discrete regions as they develop to adulthood. Typical of many migratory marine species, ontogenetic changes in habitat use throughout their decades-long juvenile stage is poorly understood, but each potential habitat has unique foraging opportunities and spatially explicit natural and anthropogenic threats that could affect key life-history parameters. 4. We found a bimodal size/age distribution in the timing that juveniles underwent an ontogenetic habitat shift from the oceanic central North Pacific (CNP) to the neritic east Pacific region near the Baja California Peninsula (BCP) (42·7 ± 7·2 vs. 68·3 ± 3·4 cm carapace length, 7·5 ± 2·7 vs. 15·6 ± 1·7 years). Important to the survival of this population, these disparate habitats differ considerably in their food availability, energy requirements and threats, and these differences can influence life-history parameters such as growth, survival and future fecundity. This is the first evidence of alternative ontogenetic shifts and habitat-use patterns for juveniles foraging in the eastern NPO. 5. We combine two techniques, skeletochronology and stable isotope analysis, to reconstruct multi-year habitat-use patterns of a remote migratory species, linked to estimated ages and body sizes of individuals, to reveal variable ontogeny during the juvenile life stage that could drive alternate life histories and that has the potential to illuminate the migration patterns for other species with accretionary tissues.

Aging is an increase in mortality risk with age due to a decline in vital functions. Research on aging has entered an exciting phase. Advances in biogerontology have demonstrated that proximate mechanisms of aging and interventions to modify lifespan are shared among species. In nature, aging patterns have proven more diverse than previously assumed. The paradigm that extrinsic mortality ultimately determines evolution of aging rates has been questioned and there appears to be a mismatch between intra‐ and inter‐specific patterns. The major challenges emerging in evolutionary ecology of aging are a lack of understanding of the complexity in functional senescence under natural conditions and unavailability of estimates of aging rates for matched populations exposed to natural and laboratory conditions. I argue that we need to reconcile laboratory and field‐based approaches to better understand (1) how aging rates (baseline mortality and the rate of increase in mortality with age) vary across populations within a species, (2) how genetic and environmental variation interact to modulate individual expression of aging rates, and (3) how much intraspecific variation in lifespan is attributable to an intrinsic (i.e., nonenvironmental) component. I suggest integration of laboratory and field assays using multiple matched populations of the same species, along with measures of functional declines. This opinion article argues that it is needed to reconcile laboratory and field‐based approaches to better understand how demographic and functional aging vary across populations within a species, how genetic and environmental variation interact to modulate individual expression of aging rates, and to examine how much intraspecific variation in lifespan is attributable to an intrinsic (i.e., nonenvironmental) component.

The evolution of life history is shaped by life expectancy. Life‐history traits coevolve, and optimal states for particular traits are constrained by trade‐offs with other life‐history traits. Life histories contrast among species, but may also diverge intraspecifically, at the level of populations. We studied the evolution of female reproductive allocation strategy, using natural populations of two sympatric species of African annual fishes, Nothobranchius furzeri and Nothobranchius orthonotus. These species inhabit pools in the Mozambican savanna that are formed in the rainy season and persist for only 2–10 months. Using 207 female N. furzeri from 11 populations and 243 female N. orthonotus from 14 populations, we tested the effects of genetic background (intraspecific lineage) and life expectancy (position on the aridity gradient determining maximum duration of their temporary habitat) on female fecundity traits. First, we found that variation in female body mass was small within populations, but varied considerably among populations. Second, we found that fecundity was largely defined by female body mass and that females spawned most of their eggs in the morning. Third, we found that the trade‐off between egg size and egg number varied among lineages of N. furzeri and this outcome has been confirmed by data from two separate years. Overall, we demonstrate that local conditions were important determinants for Nothobranchius growth and fecundity and that eggs size in arid region was less limited by female fecundity than in humid region. This article studied the evolution of female reproductive allocation in 25 wild populations of African annual fishes, Nothobranchius furzeri and Nothobranchius orthonotus, with respect to life expectancy gradient associated with aridity and pool desiccation and to population genetic background. Data did not directly support hypothesis of a higher reproductive allocation in populations with shorter life expectancy; local conditions and growth plasticity overridden potential genetic effects that can be detected under natural conditions. Eggs size in arid region, however, was less limited by female fecundity (number of eggs) than in humid region, and this relationship has been confirmed by data from two separate years.