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The Journal of Experimental Biology Jun 2024Understanding how living tissues respond to changes in their mechanical environment is a key question in evolutionary biology. Invasive species provide an ideal model...
Understanding how living tissues respond to changes in their mechanical environment is a key question in evolutionary biology. Invasive species provide an ideal model for this as they are often transplanted between environments that differ drastically in their ecological and environmental context. Spatial sorting, the name given to the phenomenon driving differences between individuals at the core and edge of an expanding range, has been demonstrated to impact the morphology and physiology of Xenopus laevis from the invasive French population. Here, we combined a structural analysis using micro-CT scanning and a functional analysis by testing the mechanical properties of the femur to test whether the increased dispersal at the range edge drives differences in bone morphology and function. Our results show significant differences in the inner structure of the femur as well as bone material properties, with frogs from the centre of the range having more robust and resistant bones. This is suggestive of an energy allocation trade-off between locomotion and investment in bone formation or alternatively may point to selection for fast locomotion at the range edge. Overall, our results further provide insights on the growth of the long bones and the formation of trabecular bone in frogs.
PubMed: 38904393
DOI: 10.1242/jeb.246419 -
Journal of Natural Products Jun 2024The adaptation of amphibians to diverse environments is closely related to the characteristics of their skin. The complex glandular system of frog skin plays a pivotal...
The adaptation of amphibians to diverse environments is closely related to the characteristics of their skin. The complex glandular system of frog skin plays a pivotal role in enabling these animals to thrive in both aquatic and terrestrial habitats and consists of crucial functions such as respiration and water balance as well as serving as a defensive barrier due to the secretion of bioactive compounds. We herein report the first investigation on the skin secretion of , as a potential source of bioactive peptides and also as an indicator of its evolutionary adaptations to changing environments. Americanin-1 was isolated and identified as a neutral peptide exhibiting moderate antibacterial activity against . Its amphipathic sequence including 19 amino acids and showing a propensity for α-helix structure is discussed. Comparisons of the histomorphology of the skin of with other previously documented species within the same genus revealed distinctive features in the Patagonian specimen, differing from conspecifics from other Argentine provinces. The presence of the Eberth-Katschenko layer, a prevalence of iridophores, and the existence of glycoconjugates in its serous glands suggest that the integument is adapted to retain skin moisture. This adaptation is consistent with the prevailing aridity of its native habitat.
PubMed: 38900961
DOI: 10.1021/acs.jnatprod.4c00184 -
Science (New York, N.Y.) Jun 2024Long associated with aging, senescent cells can promote health and have physiological roles. (Review)
Review
Long associated with aging, senescent cells can promote health and have physiological roles.
Topics: Animals; Humans; Aging; Cellular Senescence; Mice; Notophthalmus viridescens; Senotherapeutics; Drug Development
PubMed: 38900869
DOI: 10.1126/science.adj7050 -
Zoo Biology Jun 2024Boreal chorus frogs (Pseudacris maculata Agassiz 1850) are a widespread amphibian in North America, but several populations are in decline. Specifically, we are...
Boreal chorus frogs (Pseudacris maculata Agassiz 1850) are a widespread amphibian in North America, but several populations are in decline. Specifically, we are developing captive breeding and reintroduction methods for the Great Lakes/St. Lawrence-Canadian Shield population. Here we present the effects of tadpole density, food variety, and addition of supplemental minerals to rearing water on the growth, development, and survival during the larval and metamorph/juvenile stages. We conducted two experiments using a factorial design. We found that low tadpole density (1 vs. 2 tadpoles/L) and high food variety (five food items vs. three food items) significantly increased tadpole body length and Gosner stage after 2 weeks (p < .001), increased survival to metamorphosis (p < .001), decreased time to metamorphosis (p < .001), and increased weight after metamorphosis (p < .001). On average, tadpoles in the high density/low food treatment, compared to the low density/high food, were 25% smaller after 2 weeks, had 3.9× lower survival to metamorphosis, took 1.25× longer to reach metamorphosis, and weighed 1.5× less after metamorphosis. In contrast, neither density (0.5 vs. 1 tadpole/L) nor mineral supplemented water affected growth and development, but tadpole survival was higher at 1 tadpole/L. Our findings demonstrate the feasibility of rearing boreal chorus frogs in captivity and provide guidelines for rearing this and similar species in a laboratory environment.
PubMed: 38900371
DOI: 10.1002/zoo.21848 -
ELife Jun 2024Comprehensive biodiversity data is crucial for ecosystem protection. The mobile app, launched in Japan, efficiently gathers species observations from the public using...
Comprehensive biodiversity data is crucial for ecosystem protection. The mobile app, launched in Japan, efficiently gathers species observations from the public using species identification algorithms and gamification elements. The app has amassed >6 million observations since 2019. Nonetheless, community-sourced data may exhibit spatial and taxonomic biases. Species distribution models (SDMs) estimate species distribution while accommodating such bias. Here, we investigated the quality of data and its impact on SDM performance. Species identification accuracy exceeds 95% for birds, reptiles, mammals, and amphibians, but seed plants, molluscs, and fishes scored below 90%. Our SDMs for 132 terrestrial plants and animals across Japan revealed that incorporating data into traditional survey data improved accuracy. For endangered species, traditional survey data required >2000 records for accurate models (Boyce index ≥ 0.9), while blending the two data sources reduced this to around 300. The uniform coverage of urban-natural gradients by data, compared to traditional data biased towards natural areas, may explain this improvement. Combining multiple data sources better estimates species distributions, aiding in protected area designation and ecosystem service assessment. Establishing a platform for accumulating community-sourced distribution data will contribute to conserving and monitoring natural ecosystems.
Topics: Biodiversity; Animals; Smartphone; Japan; Conservation of Natural Resources; Mobile Applications; Ecosystem; Plants
PubMed: 38899444
DOI: 10.7554/eLife.93694 -
Parasitology Research Jun 2024Introduced species have a major impact on freshwater ecosystems, particularly on islands. Numerous fish species have been introduced in Corsica (Mediterranean island,...
Introduced species have a major impact on freshwater ecosystems, particularly on islands. Numerous fish species have been introduced in Corsica (Mediterranean island, southern France) as part of planned programs or clandestinely. The introduction of non-native freshwater fish species can have a range of impacts on the recipient ecosystem, including through the co-introduction of its pathogens. A sample of introduced perch Perca fluviatilis Linnaeus, 1758 from the artificial reservoir of Padula was examined following a report of parasites by an angler. The analyses revealed the occurrence of Eustrongylides sp. (Nematoda) and Clinostomum complanatum (Digenea), two zoonotic parasites in P. fluviatilis. Both parasites are reported for the first time in France. Eustrongylides sp. and C. complanatum may have been introduced with their fish intermediate hosts or through their final bird hosts. The occurrence of the two parasites raises concerns from both a veterinary and human health perspective as they can use a wide range of amphibians as intermediate hosts and can be acquired in humans through the consumption of raw or undercooked fish.
Topics: Animals; France; Fish Diseases; Perches; Introduced Species; Trematoda; Zoonoses; Trematode Infections; Islands; Humans
PubMed: 38898308
DOI: 10.1007/s00436-024-08264-4 -
Communications Biology Jun 2024DNA methylation maintenance is essential for cell fate inheritance. In differentiated cells, this involves orchestrated actions of DNMT1 and UHRF1. In mice, the...
DNA methylation maintenance is essential for cell fate inheritance. In differentiated cells, this involves orchestrated actions of DNMT1 and UHRF1. In mice, the high-affinity binding of DPPA3 to the UHRF1 PHD finger regulates UHRF1 chromatin dissociation and cytosolic localization, which is required for oocyte maturation and early embryo development. However, the human DPPA3 ortholog functions during these stages remain unclear. Here, we report the structural basis for human DPPA3 binding to the UHRF1 PHD finger. The conserved human DPPA3 VRT motif binds to the acidic surface of UHRF1 PHD finger, whereas mouse DPPA3 binding additionally utilizes two unique α-helices. The binding affinity of human DPPA3 for the UHRF1 PHD finger was weaker than that of mouse DPPA3. Consequently, human DPPA3, unlike mouse DPPA3, failed to inhibit UHRF1 chromatin binding and DNA remethylation in Xenopus egg extracts effectively. Our data provide novel insights into the distinct function and structure of human DPPA3.
Topics: Animals; Ubiquitin-Protein Ligases; Humans; CCAAT-Enhancer-Binding Proteins; Mice; Protein Binding; PHD Zinc Fingers; DNA Methylation; Chromatin; Amino Acid Sequence; Xenopus laevis
PubMed: 38898124
DOI: 10.1038/s42003-024-06434-9 -
Integrative Zoology Jun 2024Considerable research has focused on microbes on amphibian skin, as they act as the first line of defense against invading pathogens. This effort has generated...
Considerable research has focused on microbes on amphibian skin, as they act as the first line of defense against invading pathogens. This effort has generated substantial data on patterns across species, space, time, and ontogeny, alongside a growing list of beneficial antifungal symbionts. Though there is evidence of stability in amphibian skin microbial communities, there is also an indication that regular skin shedding reduces cultivable bacteria, with regrowth and recolonization in the period between sheds. This suggests that skin communities are in constant flux, and we lack an understanding of how the membership and structure of those communities are affected by shedding events. In this study, we conducted experiments on cane toads (Rhinella marina) to investigate the influence of shedding on skin microbiomes. We first used quantitative PCR to verify a positive correlation between bacterial loads and time in the days after shedding. We then resampled individuals over time to describe changes in community composition in the 38 h after shedding using amplicon sequencing. Similar to trends of bacterial loads, we found increases in alpha diversity over time after shedding, suggesting that shedding reduces bacterial diversity as it knocks down bacterial loads. During the 38-h period, community structure became similar to pre-shed communities in some individuals, but there was no consistent pattern in structural changes among individuals. In light of the amphibian chytridiomycosis pandemic, understanding how physiological events such as skin shedding affect beneficial bacteria and communities on amphibians would provide important insight into amphibian ecology.
PubMed: 38897983
DOI: 10.1111/1749-4877.12858 -
Journal of Thermal Biology Jun 2024In ectothermic vertebrates, behavioral fever, where an individual actively seeks warmer areas, seems to be a primary response to pathogens. This is considered a broad... (Review)
Review
In ectothermic vertebrates, behavioral fever, where an individual actively seeks warmer areas, seems to be a primary response to pathogens. This is considered a broad and evolutionarily conserved response among vertebrates. Recent population declines in amphibians are associated with an increase of infectious disease driven largely by climate change, habitat degradation, and pollution. Immediate action through research is required to better understand and inform conservation efforts. The literature available, does not provide unifying concepts that can guide adequate experimental protocols and interpretation of data, especially when studying animals in the field. The aim of this review is to promote common understanding of terminology and facilitating improved comprehension and application of key concepts about the occurrence of both sickness behavior or behavioral fever in ectothermic vertebrates. We start with a conceptual synthesis of sickness behavior and behavioral fever, with examples in different taxa. Through this discussion we present possible paths to standardize terminology, starting from original use in endothermic tetrapods which was expanded to ectothermic vertebrates, particularly amphibians and reptiles. This conceptual expansion from humans (endothermic vertebrates) and then to ectothermic counterparts, gravitates around the concept of 'normality'. Thus, following this discussion, we highlight caveats with experimental protocols and state the need of a reference value considered normal (RVCN), which is different from experimental control and make recommendations regarding experimental procedures and stress the value of detailed documentation of behavioral responses. We also propose some future directions that could enhance interaction among disciplines, emphasizing relationships at different levels of biological organization. This is crucial given the increasing convergence of fields such as thermal physiology, immunology, and animal behavior due to emerging diseases and other global crises impacting biodiversity.
PubMed: 38897001
DOI: 10.1016/j.jtherbio.2024.103889 -
Anais Da Academia Brasileira de Ciencias 2024The following work presents the first study applying the passive acoustic monitoring of anurans at lotic environments for a long time. This study aims to test the...
The following work presents the first study applying the passive acoustic monitoring of anurans at lotic environments for a long time. This study aims to test the efficiency of the passive acoustic monitoring method and active monitoring in detecting anurans in lotic environments of Itinguçu State Park. Specifically, we tested whether species richness differs when comparing active and passive monitoring surveys. Therefore, this study aims to test the efficiency of the passive acoustic monitoring method and active monitoring in detecting anurans in lotic environments of the Itinguçu State Park. The passive acoustic monitoring period was 72 uninterrupted hours at each collection point with intervals of 45 days. Finally, species richness was calculated, and the efficiency of the methods was compared in different scenarios. Our results demonstrated that the park has species that vocalize day and night, but most at night, there is overlapping acoustic niche; waterfall environments harm the quality of recordings; and in lotic environments the active monitoring method was more efficient than the passive acoustic monitoring in all sampling scales. Although the passive acoustic monitoring was not as efficient in a low temporal scale, it tends to increase in efficiency with longer sampling duration.
Topics: Animals; Peru; Acoustics; Anura; Parks, Recreational; Environmental Monitoring; Vocalization, Animal; Biodiversity
PubMed: 38896695
DOI: 10.1590/0001-3765202420231057