Integrative zoology最新文献

Precise quantification of the parasitic load during infections is necessary for a deep understanding of parasite-host interactions. Haemosporidians, an order of intracellular blood parasites, including agents of avian malaria and their closer relatives, have two organelles, remnants of endosymbiosis: the mitochondrion and the apicoplast, which have their own extranuclear genomes (nucleoids). While the number of organelles per parasitic cell appears to be stable, the number of their nucleoids is not, but the dynamics and factors affecting them still remain to be elucidated. We used a set of 71 blood samples of migratory birds infected by haemosporidian parasites to quantify relative DNA quantities of these two organelles through real-time quantitative PCR (qPCR). We investigated the congruence of these two parameters with the microscopically detected number of parasites, for all samples measured and for the subset of those with moderate to high parasitemia. We found that apicoplast DNA content was a better predictor for intermediate infection intensities, while mitochondrial DNA content was a better predictor for acute infections. This difference may result from the regulation of parasite intra- and inter-organellar genomic content throughout the infection stages in vertebrate hosts. Our work contributes to the methods for quantification of blood parasites in wildlife and to the understanding of their development and conservation-relevant consequences for the avian hosts.

Amphibians host a diverse array of macro and microparasites, and these relationships can provide relevant information for assessing and monitoring population and ecosystem health. The dynamics and outcomes of these host-parasite interactions are influenced by several biotic and abiotic factors, as well as by the characteristics of both the parasite and the host. This study aims to identify hemoparasites in Pleurodema thaul (four-eyed frog) (Leptodactylidae) across its extensive distribution in Chile and to explore potential relationships between parasite occurrence, host traits, and habitat variables. To achieve this, we surveyed P. thaul populations from 40 localities between the extreme north and south of Chile (22-43°S), in a latitudinal gradient of 2500 km. In each locality, individuals were actively searched along the margin of water bodies, manually captured, sexed, and measured using standard morphometric and biosecurity protocols. Blood samples were collected via facial vein puncture using needles and heparinized capillary tubes. Smears were prepared on-site, fixed with methanol, and stained with 10% Giemsa for subsequent microscopic analysis at 40× and 100× magnification. Hemoparasites were detected in 61% (221/363) of individuals, with three genera identified: the hemogregarines Hepatozoon sp. and Dactylosoma sp. (Adeleorina), with a prevalence of 7% and 39%, respectively, and the hemococcidium Lankesterella sp. (Eimeriorina), with 22%. The study describes the key characteristics of these parasites in both intra- and extracellular developmental stages. These findings contribute to the understanding of anuran hemoparasites by expanding knowledge on their distribution, morphological traits, and local and regional host-parasite interactions.

Avian blood parasites of the genera Plasmodium, Haemoproteus, and Leucocytozoon are typically identified through Sanger sequencing of a partial cytochrome b fragment, the MalAvi barcoding region. This approach limits the detection of mixed infections and the relative frequencies of co-infecting parasites. In contrast, next-generation sequencing (NGS) can resolve these problems but has been underused for haemosporidian lineage identification in samples from the wild. We used an improved PCR protocol and sequencing with Illumina MiSeq to determine haemosporidian assemblages in wild birds captured at a migration stopover site in Bulgaria, Europe. From 406 samples obtained from 52 bird species, we detected 81 haemosporidian lineages in 131 infected samples from 32 species (32% prevalence). On average, individuals were infected with 2.4 lineages, with 59 birds infected by a single lineage, and 21 birds infected with 5-9 lineages. A subset of samples was Illumina- and Sanger-sequenced in parallel, finding mixed infections in 72 samples and 8× higher detection rate of mixed and co-infections through high-throughput sequencing. Both methods identified the same dominant (co-infecting) lineage (91%). Metabarcoding identified common mixed infections of sister lineage groups ("sisterhoods") known for prevalent lineages and morphospecies, including Plasmodium relictum p_SGS1, Haemoproteus motacillae h_YWT2, and Haemoproteus parabelopolskyi h_SYAT01. Some other lineages appeared consistently more dominant. Our study shows that in some host communities, metabarcoding can reveal a great diversity of mixed infections. This opens new horizons to the study of assemblages of haemosporidian parasites, their interactions within individual hosts, and co-evolution with other members of the blood microbiome and the hosts.

Evolutionary and behavioral adaptations are frequently linked to animal sensory perception. Echolocators have evolved instantaneous and highly adaptive control over their sensory and motor actions enabling them to detect and capture rapidly moving, evasive prey in three-dimensional space. Specifically, among volant bats, maneuverability decreases with increasing mass, while toothed whales and dolphins have evolved tight turning rates and radii to enable them to capture small and elusive fish. We thus hypothesize that selection pressures should have driven the evolution of relatively smaller body size among echolocators to enhance their agility. To test this, we conducted PGLS and GLMM model analyses comparing the body mass of 1327 echolocating species with 4878 non-echolocating species. In support of our body size filtering hypothesis, echolocating species tended to be significantly smaller than their non-echolocating relatives across the entire body mass range, both generally and at the order and family levels. Furthermore, our findings transcended the concurrent effects of habitat type and dietary preferences on modulating body size distributions, as well as ecogeographical rules relating to the evolution of body size. This shows that the echolocator-body size relationship has evolved independently across vertebrate taxa that diverged millions of years ago. Nevertheless, the resultant diversity of extant, relatively small echolocating species and the key functional roles they play in ecosystems may be vulnerable to contemporary anthropogenic disturbances.

The diversification of advertisement calls is largely driven by climatic niche differentiation. Our results provide acoustic evidence for studies on ecological speciation in anurans.

Although the effects of social rank on behavior and physiology are well established, their relationship with gut microbiota is not yet fully understood. We investigated how social rank affects physiological responses, gut microbiota, and metabolites in the greater long-tailed hamster (Tscherskia triton), a naturally solitary rodent. Dominant male hamsters displayed a "high-vigilance, metabolically activated" phenotype, characterized by increased aggression, elevated serum corticosterone (CORT) and serotonin (5-HT) levels, and activation of the paraventricular nucleus, a key regulator of the hypothalamic-pituitary-adrenal axis. In contrast, subordinates exhibited lower CORT and 5-HT levels, with increased activation of the arcuate nucleus (ARC), suggesting a more energy-conserving and stress-resilient phenotype. Social rank strongly shaped gut microbiota and metabolic output: dominants were enriched in energy-harvesting taxa (e.g., Limosilactobacillus and Alistipes) and had higher fecal queuine levels, a metabolite derived from gut microbiota. Conversely, subordinates were enriched in immunomodulatory taxa (e.g., Faecalibacterium and Butyrivibrio). These findings suggest that dominance in solitary species may be supported by coordinated host-microbiome interactions, which meet high energetic demands while maintaining stress resilience. This provides a novel framework for understanding the gut-brain-microbiome axis in social dominance.

Plant-insect interactions form a dynamic, co-evolutionary interface where plant secondary metabolites (SMs) act as central mediators. Shaped by both biotic and abiotic factors, these metabolites function beyond mere toxicity, modulating insect behavior, enabling multitrophic communication, and integrating environmental cues across ecological dimensions.

Prescribed burning programs are implemented in some protected areas to reintroduce fire as a disturbance and to control the lignification of palm savannas. The objective of this study was to determine the effects of fires and other environmental factors on medium and large animal species in a protected palm savanna in Central Argentina. Eight seasonal samplings were conducted across 58 sites, including burned and non-burned areas. At each site, a band transect of 400 × 6 m was surveyed to record footprints and feces. Also, for each site, 19 environmental variables were recorded. The association between habitat use by different species and fire and environmental factors was analyzed using generalized linear mixed models. Signs belonging to five species, Rhea americana, Hydrochoerus hydrochaeris, Subulo gouazoubira, Axis axis, and Sus scrofa, and two families, foxes and small felines, were found. Some of the native species, such as R. americana, H. hydrochaeris and foxes were indeed affected in the short term (2-12 months) by the fire. In contrast, the two exotic species, A. axis and S. scrofa, showed no direct relationship with any fire variable. In general terms, fires had evident effects on native fauna, while they are likely to affect exotic species more indirectly by limiting the expansion of shrubland areas, which are most commonly used by these species.

Parasitic infections remain major global health challenges, particularly in low- and middle-income countries. Although traditional vaccines have made significant progress against parasites, limited success has been obtained due to the parasites' complex life cycles and immune evasion. Nanoparticle-based vaccines, including mRNA-lipid particles, polymeric particles, and virus-like particles (VLPs), offer a promising alternative, showing improved immunogenicity in trials. In this study, the recent advancements in nanoparticle-based vaccines for parasitic infections and the roles of various types of nanoparticles are summarized in detail. Furthermore, the existing challenges regarding the parasite nanovaccines, such as clinical, ethical, and regulatory hurdles, are analyzed, and the constructive perspectives for future studies are provided simultaneously. This review will contribute to the understanding of functions and the current status of parasite nanovaccines, prompting the development of next-generation parasite nanovaccines.

In the inaugural editorial of Integrative Zoology (INZ), the founding vision was clear: represent and re-unite our various sub-disciplines and provide a basis for a comprehensive understanding of zoological phenomena at all levels.