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1.
Proc Natl Acad Sci U S A ; 121(30): e2403691121, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39018198

RESUMO

The global biodiversity that underpins wild food systems-including fisheries-is rapidly declining. Yet, we often have only a limited understanding of how households use and benefit from biodiversity in the ecosystems surrounding them. Explicating these relationships is critical to forestall and mitigate the effects of biodiversity declines on food and nutrition security. Here, we quantify how biodiversity filters from ecosystems to household harvest, consumption, and sale, and how ecological traits and household characteristics shape these relationships. We used a unique, integrated ecological (40 sites, quarterly data collection) and household survey (n = 414, every 2 mo data collection) dataset collected over 3 y in rice field fisheries surrounding Cambodia's Tonlé Sap, one of Earth's most productive and diverse freshwater systems. While ecosystem biodiversity was positively associated with household catch, consumption, and sold biodiversity, households consumed an average of 43% of the species present in the ecosystem and sold only 9%. Larger, less nutritious, and more common species were disproportionally represented in portfolios of commercially traded species, while consumed species mirrored catches. The relationship between ecosystem and consumed biodiversity was remarkably consistent across variation in household fishing effort, demographics, and distance to nearest markets. Poorer households also consumed more species, underscoring how wild food systems may most benefit the vulnerable. Our findings amplify concerns about the impacts of biodiversity loss on our global food systems and highlight that utilization of biodiversity for consumption may far exceed what is commercially traded.


Assuntos
Biodiversidade , Características da Família , Pesqueiros , Peixes , Animais , Camboja , Humanos , Ecossistema , Conservação dos Recursos Naturais , Abastecimento de Alimentos , Comércio
2.
Proc Natl Acad Sci U S A ; 121(22): e2306229121, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38722826

RESUMO

The Amazon River Basin's extraordinary social-ecological system is sustained by various water phases, fluxes, and stores that are interconnected across the tropical Andes mountains, Amazon lowlands, and Atlantic Ocean. This "Andes-Amazon-Atlantic" (AAA) pathway is a complex hydroclimatic system linked by the regional water cycle through atmospheric circulation and continental hydrology. Here, we aim to articulate the AAA hydroclimate pathway as a foundational system for research, management, conservation, and governance of aquatic systems of the Amazon Basin. We identify and describe the AAA pathway as an interdependent, multidirectional, and multiscale hydroclimate system. We then present an assessment of recent (1981 to 2020) changes in the AAA pathway, primarily reflecting an acceleration in the rates of hydrologic fluxes (i.e., water cycle intensification). We discuss how the changing AAA pathway orchestrates and impacts social-ecological systems. We conclude with four recommendations for the sustainability of the AAA pathway in ongoing research, management, conservation, and governance.

3.
Proc Natl Acad Sci U S A ; 121(14): e2313305121, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38527195

RESUMO

Aquatic locomotion is challenging for land-dwelling creatures because of the high degree of fluidity with which the water yields to loads. We surprisingly found that the Chinese rice grasshopper Oxya chinensis, known for its terrestrial acrobatics, could swiftly launch itself off the water's surface in around 25 ms and seamlessly transition into flight. Biological observations showed that jumping grasshoppers use their front and middle legs to tilt up bodies first and then lift off by propelling the water toward the lower back with hind legs at angular speeds of up to 18°/ms, whereas the swimming grasshoppers swing their front and middle legs in nearly horizontal planes and move hind legs less violently (~8°/ms). Force measurement and model analysis indicated that the weight support could be achieved by hydrostatics which are proportionate to the mass of the grasshoppers, while the propulsions for motion are derived from the controlled limb-water interactions (i.e., the hydrodynamics). After learning the structural and behavioral strategies of the grasshoppers, a robot was created and was capable of swimming and jumping on the water surface like the insects, further demonstrating the effectiveness of decoupling the challenges of aquatic locomotion by the combined use of the static and dynamic hydro forces. This work not only uncovered the combined mechanisms responsible for facilitating aquatic acrobatics in this species but also laid a foundation for developing bioinspired robots that can locomote across multiple media.


Assuntos
Gafanhotos , Robótica , Animais , Locomoção , Insetos , Água , Fenômenos Biomecânicos
4.
Annu Rev Microbiol ; 75: 337-357, 2021 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-34351793

RESUMO

Since the emergence of the first fungi some 700 million years ago, unicellular yeast-like forms have emerged multiple times in independent lineages via convergent evolution. While tens to hundreds of millions of years separate the independent evolution of these unicellular organisms, they share remarkable phenotypic and metabolic similarities, and all have streamlined genomes. Yeasts occur in every aquatic environment yet examined. Many species are aquatic; perhaps most are amphibious. How these species have evolved to thrive in aquatic habitats is fundamental to understanding functions and evolutionary mechanisms in this unique group of fungi. Here we review the state of knowledge of the physiological and ecological diversity of amphibious yeasts and their key evolutionary adaptations enabling survival in aquatic habitats. We emphasize some genera previously thought to be exclusively terrestrial. Finally, we discuss the ability of many yeasts to survive in extreme habitats and how this might lend insight into ecological plasticity, including amphibious lifestyles.


Assuntos
Evolução Biológica , Ecossistema , Adaptação Fisiológica , Fungos/genética
5.
Proc Natl Acad Sci U S A ; 119(36): e2116841119, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-36037379

RESUMO

Most of the described species in kingdom Fungi are contained in two phyla, the Ascomycota and the Basidiomycota (subkingdom Dikarya). As a result, our understanding of the biology of the kingdom is heavily influenced by traits observed in Dikarya, such as aerial spore dispersal and life cycles dominated by mitosis of haploid nuclei. We now appreciate that Fungi comprises numerous phylum-level lineages in addition to those of Dikarya, but the phylogeny and genetic characteristics of most of these lineages are poorly understood due to limited genome sampling. Here, we addressed major evolutionary trends in the non-Dikarya fungi by phylogenomic analysis of 69 newly generated draft genome sequences of the zoosporic (flagellated) lineages of true fungi. Our phylogeny indicated five lineages of zoosporic fungi and placed Blastocladiomycota, which has an alternation of haploid and diploid generations, as branching closer to the Dikarya than to the Chytridiomyceta. Our estimates of heterozygosity based on genome sequence data indicate that the zoosporic lineages plus the Zoopagomycota are frequently characterized by diploid-dominant life cycles. We mapped additional traits, such as ancestral cell-cycle regulators, cell-membrane- and cell-wall-associated genes, and the use of the amino acid selenocysteine on the phylogeny and found that these ancestral traits that are shared with Metazoa have been subject to extensive parallel loss across zoosporic lineages. Together, our results indicate a gradual transition in the genetics and cell biology of fungi from their ancestor and caution against assuming that traits measured in Dikarya are typical of other fungal lineages.


Assuntos
Fungos , Estágios do Ciclo de Vida , Filogenia , Diploide , Fungos/classificação , Fungos/genética , Genoma Fúngico/genética
6.
Proc Natl Acad Sci U S A ; 119(22): e2120817119, 2022 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-35605118

RESUMO

Fish are an important source of bioavailable micronutrients and essential fatty acids, and capture fisheries have potential to substantially reduce dietary deficiencies. Vigorous debate has focused on trade and fishing in foreign waters as drivers of inequitable distribution of volume and value of fish, but their impact on nutrient supplies from fish is unknown. We analyze global catch, trade, and nutrient composition data for marine fisheries to quantify distribution patterns among countries with differing prevalence of inadequate nutrient intake. We find foreign fishing relocates 1.5 times more nutrients than international trade in fish. Analysis of nutrient flows among countries of different levels of nutrient intake shows fishing in foreign waters predominantly (but not exclusively) benefits nutrient-secure nations, an outcome amplified by trade. Next, we developed a nutritional vulnerability framework that shows those small island developing states and/or African nations currently benefiting from trade and foreign fishing, and countries with low adaptive capacity, are most vulnerable to future changes in nutrient supplies. Climate change exacerbates vulnerabilities for many nations. Harnessing the potential of global fisheries to address dietary deficiencies will require greater attention to nutrition objectives in fisheries' licensing deals and trade negotiations.


Assuntos
Internacionalidade , Desnutrição , Animais , Comércio , Conservação dos Recursos Naturais , Pesqueiros , Peixes , Abastecimento de Alimentos , Humanos , Caça , Nutrientes
7.
Proc Natl Acad Sci U S A ; 119(8)2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35165193

RESUMO

Environmental exposure to active pharmaceutical ingredients (APIs) can have negative effects on the health of ecosystems and humans. While numerous studies have monitored APIs in rivers, these employ different analytical methods, measure different APIs, and have ignored many of the countries of the world. This makes it difficult to quantify the scale of the problem from a global perspective. Furthermore, comparison of the existing data, generated for different studies/regions/continents, is challenging due to the vast differences between the analytical methodologies employed. Here, we present a global-scale study of API pollution in 258 of the world's rivers, representing the environmental influence of 471.4 million people across 137 geographic regions. Samples were obtained from 1,052 locations in 104 countries (representing all continents and 36 countries not previously studied for API contamination) and analyzed for 61 APIs. Highest cumulative API concentrations were observed in sub-Saharan Africa, south Asia, and South America. The most contaminated sites were in low- to middle-income countries and were associated with areas with poor wastewater and waste management infrastructure and pharmaceutical manufacturing. The most frequently detected APIs were carbamazepine, metformin, and caffeine (a compound also arising from lifestyle use), which were detected at over half of the sites monitored. Concentrations of at least one API at 25.7% of the sampling sites were greater than concentrations considered safe for aquatic organisms, or which are of concern in terms of selection for antimicrobial resistance. Therefore, pharmaceutical pollution poses a global threat to environmental and human health, as well as to delivery of the United Nations Sustainable Development Goals.


Assuntos
Rios/química , Poluição Química da Água/análise , Poluição Química da Água/prevenção & controle , Ecossistema , Exposição Ambiental , Monitoramento Ambiental , Humanos , Preparações Farmacêuticas , Águas Residuárias/análise , Águas Residuárias/química , Água/análise , Água/química , Poluentes Químicos da Água/análise
8.
Proc Natl Acad Sci U S A ; 119(26): e2102466119, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35733249

RESUMO

Severe deterioration of water quality in lakes, characterized by overabundance of algae and declining dissolved oxygen in the deep lake (DOB), was one of the ecological crises of the 20th century. Even with large reductions in phosphorus loading, termed "reoligotrophication," DOB and chlorophyll (CHL) have often not returned to their expected pre-20th-century levels. Concurrently, management of lake health has been confounded by possible consequences of climate change, particularly since the effects of climate are not neatly separable from the effects of eutrophication. Here, using Lake Geneva as an iconic example, we demonstrate a complementary alternative to parametric models for understanding and managing lake systems. This involves establishing an empirically-driven baseline that uses supervised machine learning to capture the changing interdependencies among biogeochemical variables and then combining the empirical model with a more conventional equation-based model of lake physics to predict DOB over decadal time-scales. The hybrid model not only leads to substantially better forecasts, but also to a more actionable description of the emergent rates and processes (biogeochemical, ecological, etc.) that drive water quality. Notably, the hybrid model suggests that the impact of a moderate 3°C air temperature increase on water quality would be on the same order as the eutrophication of the previous century. The study provides a template and a practical path forward to cope with shifts in ecology to manage environmental systems for non-analogue futures.


Assuntos
Lagos , Qualidade da Água , Ecossistema , Monitoramento Ambiental , Eutrofização , Lagos/química , Fósforo/análise , Suíça
9.
BMC Genomics ; 25(1): 648, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38943098

RESUMO

BACKGROUND: Lotus (Nelumbo nucifera G.) is an important aquatic plant with high ornamental, economic, cultural and ecological values, but abiotic stresses seriously affect its growth and distribution. Q-type C2H2 zinc finger proteins (ZFPs) play an important role in plant growth development and environmental stress responses. Although the Q-type C2H2 gene family has been identified in some plants, limited reports has been carried out it in lotus. RESULTS: In this study, we identified 45 Q-type NnZFP members in lotus. Based on the phylogenetic tree, these Q-type NnZFP gene family members were divided into 4 groups, including C1-1i, C1-2i, C1-3i and C1-4i. Promoter cis-acting elements analysis indicated that most Q-type NnZFP gene family members in lotus were associated with response to abiotic stresses. Through collinearity analyses, no tandem duplication gene pairs and 14 segmental duplication gene pairs were identified, which showed that duplication events might play a key role in the expansion of the Q-type NnZFP gene family. The synteny results suggested that 54 and 28 Q-type NnZFP genes were orthologous to Arabidopsis and rice, respectively. The expression patterns of these Q-type NnZFP genes revealed that 30 Q-type NnZFP genes were expressed in at least one lotus tissue. Nn5g30550 showed relatively higher expression levels in all tested tissues. 12 genes were randomly selected with at least one gene from each phylogenetic clade, and the expression of these selected genes were confirmed by qRT-PCR (quantitative real-time polymerase chain reaction). The results indicated that Q-type NnZFP genes were extensively involved in cadmium, drought, salt and cold stresses responses. Among them, 11 genes responded to at least three different stress treatments, especially Nn2g12894, which induced by all four treatments. CONCLUSIONS: These results could increase our understanding of the characterization of the Q-type NnZFP gene family and provide relevant information for further functional analysis of Q-type NnZFP genes in plant development, and abiotic stress tolerance in lotus.


Assuntos
Regulação da Expressão Gênica de Plantas , Família Multigênica , Nelumbo , Filogenia , Proteínas de Plantas , Estresse Fisiológico , Estresse Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Nelumbo/genética , Dedos de Zinco CYS2-HIS2/genética , Lotus/genética , Lotus/metabolismo , Lotus/crescimento & desenvolvimento , Genoma de Planta , Perfilação da Expressão Gênica
10.
Ecol Lett ; 27(3): e14401, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38468439

RESUMO

Ecosystems that are coupled by reciprocal flows of energy and nutrient subsidies can be viewed as a single "meta-ecosystem." Despite these connections, the reciprocal flow of subsidies is greatly asymmetrical and seasonally pulsed. Here, we synthesize existing literature on stream-riparian meta-ecosystems to quantify global patterns of the amount of subsidy consumption by organisms, known as "allochthony." These resource flows are important since they can comprise a large portion of consumer diets, but can be disrupted by human modification of streams and riparian zones. Despite asymmetrical subsidy flows, we found stream and riparian consumer allochthony to be equivalent. Although both fish and stream invertebrates rely on seasonally pulsed allochthonous resources, we find allochthony varies seasonally only for fish, being nearly three times greater during the summer and fall than during the winter and spring. We also find that consumer allochthony varies with feeding traits for aquatic invertebrates, fish, and terrestrial arthropods, but not for terrestrial vertebrates. Finally, we find that allochthony varies by climate for aquatic invertebrates, being nearly twice as great in arid climates than in tropical climates, but not for fish. These findings are critical to understanding the consequences of global change, as ecosystem connections are being increasingly disrupted.


Assuntos
Ecossistema , Rios , Animais , Humanos , Cadeia Alimentar , Invertebrados , Peixes
11.
Emerg Infect Dis ; 30(4): 766-769, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38526207

RESUMO

We describe a classic case of nasal rhinosporidiosis in a woman who resided in Johannesburg, South Africa, but originated from a rural area in Eastern Cape Province. We confirmed histologic diagnosis using PCR testing and compared details with those from records on 17 other cases from South Africa.


Assuntos
Rinosporidiose , Feminino , Humanos , África do Sul/epidemiologia , Rinosporidiose/diagnóstico , Nariz
12.
Curr Issues Mol Biol ; 46(7): 7353-7372, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39057077

RESUMO

Eriocheir sinensis is an economically important aquatic animal. Its regulatory mechanisms underlying many biological processes are still vague due to the lack of systematic analysis tools. The protein-protein interaction network (PIN) is an important tool for the systematic analysis of regulatory mechanisms. In this work, a novel machine learning method, DGO-SVM, was applied to predict the protein-protein interaction (PPI) in E. sinensis, and its PIN was reconstructed. With the domain, biological process, molecular functions and subcellular locations of proteins as the features, DGO-SVM showed excellent performance in Bombyx mori, humans and five aquatic crustaceans, with 92-96% accuracy. With DGO-SVM, the PIN of E. sinensis was reconstructed, containing 14,703 proteins and 7,243,597 interactions, in which 35,604 interactions were associated with 566 novel proteins mainly involved in the response to exogenous stimuli, cellular macromolecular metabolism and regulation. The DGO-SVM demonstrated that the biological process, molecular functions and subcellular locations of proteins are significant factors for the precise prediction of PPIs. We reconstructed the largest PIN for E. sinensis, which provides a systematic tool for the regulatory mechanism analysis. Furthermore, the novel-protein-related PPIs in the PIN may provide important clues for the mechanism analysis of the underlying specific physiological processes in E. sinensis.

13.
Funct Integr Genomics ; 24(3): 110, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806846

RESUMO

With the growing population, demand for food has dramatically increased, and fisheries, including aquaculture, are expected to play an essential role in sustaining demand with adequate quantities of protein and essential vitamin supplements, employment generation, and GDP growth. Unfortunately, the incidence of emerging/re-emerging AMR pathogens annually occurs because of anthropogenic activities and the frequent use of antibiotics in aquaculture. These AMR pathogens include the WHO's top 6 prioritized ESKAPE pathogens (nosocomial pathogens: Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.), extended-spectrum beta lactases (ESBLs) and carbapenemase-producing E. coli, which pose major challenges to the biomagnification of both nonnative and native antibiotic-resistant bacteria in capture and cultured fishes. Although implementing the rational use of antibiotics represents a promising mitigation measure, this approach is practically impossible due to the lack of awareness among farmers about the interplay between antimicrobial use and the emergence of antimicrobial resistance (AMR). Nevertheless, to eradicate these 'superbugs,' CRISPR/Cas (clustered regularly interspersed short palindromic repeats/CRISPR associate protein) has turned out to be a novel approach owing to its ability to perform precise site-directed targeting/knockdown/reversal of specific antimicrobial resistance genes in vitro and to distinguish AMR-resistant bacteria from a plethora of commensal aquatic bacteria. Along with highlighting the importance of virulent multidrug resistance genes in bacteria, this article aims to provide a holistic picture of CRISPR/Cas9-mediated genome editing for combating antimicrobial-resistant bacteria isolated from various aquaculture and marine systems, as well as insights into different types of CRISPR/Cas systems, delivery methods, and challenges associated with developing CRISPR/Cas9 antimicrobial agents.


Assuntos
Sistemas CRISPR-Cas , Animais , Edição de Genes , Farmacorresistência Bacteriana/genética , Bactérias/genética , Bactérias/efeitos dos fármacos , Antibacterianos/farmacologia , Ecossistema , Peixes/microbiologia , Peixes/genética , Aquicultura
14.
J Mol Evol ; 92(3): 300-316, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38735005

RESUMO

Cetaceans and pinnipeds are lineages of mammals that have independently returned to the aquatic environment, acquiring varying degrees of dependence on it while sharing adaptations for underwater living. Here, we focused on one critical adaptation from both groups, their ability to withstand the ischemia and reperfusion experienced during apnea diving, which can lead to the production of reactive oxygen species (ROS) and subsequent oxidative damage. Previous studies have shown that cetaceans and pinnipeds possess efficient antioxidant enzymes that protect against ROS. In this study, we investigated the molecular evolution of key antioxidant enzyme genes (CAT, GPX3, GSR, PRDX1, PRDX3, and SOD1) and the ROS-producing gene XDH, in cetaceans and pinnipeds lineages. We used the ratio of non-synonymous (dN) to synonymous (dS) substitutions as a measure to identify signatures of adaptive molecular evolution in these genes within and between the two lineages. Additionally, we performed protein modeling and variant impact analyzes to assess the functional consequences of observed mutations. Our findings revealed distinct selective regimes between aquatic and terrestrial mammals in five of the examined genes, including divergences within cetacean and pinniped lineages, between ancestral and recent lineages and between crowns groups. We identified specific sites under positive selection unique to Cetacea and Pinnipedia, with one site showing evidence of convergent evolution in species known for their long and deep-diving capacities. Notably, many sites under adaptive selection exhibited radical changes in amino acid properties, with some being damaging mutations in human variations, but with no apparent detrimental impacts on aquatic mammals. In conclusion, our study provides insights into the adaptive changes that have occurred in the antioxidant systems of aquatic mammals throughout their evolutionary history. We observed both distinctive features within each group of Cetacea and Pinnipedia and instances of convergence. These findings highlight the dynamic nature of the antioxidant system in response to challenges of the aquatic environment and provide a foundation for further investigations into the molecular mechanisms underlying these adaptations.


Assuntos
Antioxidantes , Caniformia , Cetáceos , Evolução Molecular , Animais , Cetáceos/genética , Cetáceos/metabolismo , Caniformia/genética , Antioxidantes/metabolismo , Filogenia , Adaptação Fisiológica/genética , Espécies Reativas de Oxigênio/metabolismo , Seleção Genética
15.
Am Nat ; 203(5): 618-627, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38635364

RESUMO

AbstractAutonomous sensors provide opportunities to observe organisms across spatial and temporal scales that humans cannot directly observe. By processing large data streams from autonomous sensors with deep learning methods, researchers can make novel and important natural history discoveries. In this study, we combine automated acoustic monitoring with deep learning models to observe breeding-associated activity in the endangered Sierra Nevada yellow-legged frog (Rana sierrae), a behavior that current surveys do not measure. By deploying inexpensive hydrophones and developing a deep learning model to recognize breeding-associated vocalizations, we discover three undocumented R. sierrae vocalization types and find an unexpected temporal pattern of nocturnal breeding-associated vocal activity. This study exemplifies how the combination of autonomous sensor data and deep learning can shed new light on species' natural history, especially during times or in locations where human observation is limited or impossible.


Assuntos
Ranidae , Vocalização Animal , Animais , Humanos , Acústica
16.
BMC Plant Biol ; 24(1): 449, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783181

RESUMO

Drosera intermedia grows in acidic bogs in parts of valleys that are flooded in winter, and that often dry out in summer. It is also described as the sundew of the most heavily hydrated habitats in peatlands, and it is often found in water and even underwater. This sundew is the only one that can tolerate long periods of submersion, and more importantly produces a typical submerged form that can live in such conditions for many years. Submerged habitats are occupied by D. intermedia relatively frequently. The aim of the study was to determine the environmental conditions and architecture of individuals in the submerged form of D. intermedia. The features of the morphological and anatomical structure and chlorophyll a fluorescence of this form that were measured were compared with analogous ones in individuals that occurred in emerged and peatland habitats. The submerged form occurred to a depth of 20 cm. Compared to the other forms, its habitat had the highest pH (4.71-4.92; Me = 4.71), the highest temperature and substrate hydration, and above all, the lowest photosynthetically active radiation (PAR; 20.4-59.4%). This form differed from the other forms in almost all of the features of the plant's architecture. It is particularly noteworthy that it had the largest main axis height among all of the forms, which exceeded 18 cm. The number of living leaves in a rosette was notable (18.1 ± 8.1), while the number of dead leaves was very low (6.9 ± 3.8). The most significant differences were in the shape of its submerged leaves, in which the length of the leaf blade was the lowest of all of the forms (0.493 ± 0.15 mm; p < 0.001) and usually the widest. The stem cross-sectional area was noticeably smaller in the submerged form than in the other forms, the xylem was less developed and collaterally closed vascular bundles occurred. Our analysis of the parameters of chlorophyll fluorescence in vivo revealed that the maximum quantum yield of the primary photochemistry of photosystem II is the highest for the submerged form (Me = 0.681), the same as the maximum quantum yield of the electron transport (Me φE0 = 0.183). The efficiency of energy use per one active reaction center of photosystem II (RC) was the lowest in the submerged form (Me = 2.978), same as the fraction of energy trapped by one active RC (Me = 1.976) and the non-photochemical energy dissipation (DI0/RC; Me = 0.916). The ET0/RC parameter, associated with the efficiency of the energy utilization for electron transport by one RC, in the submerged plant reached the highest value (Me = 0.489). The submerged form of D. intermedia clearly differed from the emerged and peatland forms in its plant architecture. The submerged plants had a thinner leaf blade and less developed xylem than the other forms, however, their stems were much longer. The relatively high photosynthetic efficiency of the submerged forms suggests that most of the trapped energy is utilized to drive photosynthesis with a minimum energy loss, which may be a mechanism to compensate for the relatively small size of the leaf blade.


Assuntos
Clorofila , Fotossíntese , Fotossíntese/fisiologia , Clorofila/metabolismo , Folhas de Planta/fisiologia , Folhas de Planta/anatomia & histologia , Folhas de Planta/crescimento & desenvolvimento , Ecossistema , Clorofila A/metabolismo , Temperatura , Concentração de Íons de Hidrogênio , Água/metabolismo
17.
Proc Biol Sci ; 291(2026): 20240514, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38955232

RESUMO

Caddisflies (Trichoptera) are among the most diverse groups of freshwater animals with more than 16 000 described species. They play a fundamental role in freshwater ecology and environmental engineering in streams, rivers and lakes. Because of this, they are frequently used as indicator organisms in biomonitoring programmes. Despite their importance, key questions concerning the evolutionary history of caddisflies, such as the timing and origin of larval case making, remain unanswered owing to the lack of a well-resolved phylogeny. Here, we estimated a phylogenetic tree using a combination of transcriptomes and targeted enrichment data for 207 species, representing 48 of 52 extant families and 174 genera. We calibrated and dated the tree with 33 carefully selected fossils. The first caddisflies originated approximately 295 million years ago in the Permian, and major suborders began to diversify in the Triassic. Furthermore, we show that portable case making evolved in three separate lineages, and shifts in diversification occurred in concert with key evolutionary innovations beyond case making.


Assuntos
Insetos , Filogenia , Insetos/classificação , Insetos/genética , Insetos/fisiologia , Água Doce , Transcriptoma , Biodiversidade , Fósseis , Evolução Biológica , Animais
18.
Proc Biol Sci ; 291(2023): 20240172, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38772418

RESUMO

Tests for the role of species' relative dispersal abilities in ecological and biogeographical models rely heavily on dispersal proxies, which are seldom substantiated by empirical measures of actual dispersal. This is exemplified by tests of dispersal-range size relationships and by metacommunity research that often features invertebrates, particularly freshwater insects. Using rare and unique empirical data on dispersal abilities of caddisflies, we tested whether actual dispersal abilities were associated with commonly used dispersal proxies (metrics of wing size and shape; expert opinion). Across 59 species in 12 families, wing morphology was not associated with actual dispersal. Within some families, individual wing metrics captured some dispersal differences among species, although useful metrics varied among families and predictive power was typically low. Dispersal abilities assigned by experts were either no better than random or actually poorer than random. Our results cast considerable doubt on research underpinned by dispersal proxies and scrutiny of previous research results may be warranted. Greater progress may lie in employing innovative survey and experimental design to measure actual dispersal in the field.


Assuntos
Distribuição Animal , Insetos , Asas de Animais , Animais , Asas de Animais/anatomia & histologia , Asas de Animais/fisiologia , Insetos/fisiologia
19.
Proc Biol Sci ; 291(2032): 20241106, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39378996

RESUMO

Cetaceans have evolved unique limb structures, such as flippers, due to genetic changes during their transition to aquatic life. However, the full understanding of the genetic and evolutionary mechanisms behind these changes is still developing. By examining 25 limb-related protein-coding genes across various mammalian species, we compared genetic changes between aquatic mammals, like whales, and other mammals with unique limb structures such as bats, rodents and elephants. Our findings revealed significant modifications in limb-related genes, including variations in the Hox, GDF5 and Evx genes. Notably, a relaxed selection in several key genes was observed, suggesting a lifting of developmental constraints, which might have facilitated the emergence of morphological innovations in cetacean limb morphology. We also uncovered non-synonymous changes, insertions and deletions in these genes, particularly in the polyalanine tract of HOXD13, which are distinctive to cetaceans or convergent with other aquatic mammals. These genetic variations correlated with the diverse and specialized limb structures observed in cetaceans, indicating a complex interplay of relaxed selection and specific mutations in mammalian limb evolution.


Assuntos
Cetáceos , Membro Anterior , Mamíferos , Animais , Cetáceos/genética , Cetáceos/anatomia & histologia , Mamíferos/genética , Mamíferos/anatomia & histologia , Membro Anterior/anatomia & histologia , Evolução Biológica , Seleção Genética , Evolução Molecular
20.
J Exp Zool B Mol Dev Evol ; 342(3): 278-290, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38185943

RESUMO

Development of reliable germplasm repositories is critical for preservation of genetic resources of aquatic species, which are widely utilized to support biomedical innovation by providing a foundational source for naturally occurring variation and development of new variants through genetic manipulations. A significant barrier in repository development is the lack of cryopreservation capability and reproducibility across the research community, posing great risks of losing advances developed from billions of dollars of research investment. The emergence of open scientific hardware has fueled a new movement across biomedical research communities. With the increasing accessibility of consumer-level fabrication technologies, such as three-dimensional printers, open hardware devices can be custom designed, and design files distributed to community members for enhancing rigor, reproducibility, and standardization. The overall goal of this review is to explore pathways to create open-hardware ecosystems among the communities using aquatic model resources for biomedical research. To gain feedback and insights from community members, an interactive workshop focusing on open-hardware applications in germplasm repository development was held at the 2022 Aquatic Models for Human Disease Conference, Woods Hole, Massachusetts. This work integrates conceptual strategies with practical insights derived from workshop interactions using examples of germplasm repository development. These insights can be generalized for establishment of open-hardware ecosystems for a broad biomedical research community. The specific objectives were to: (1) introduce an open-hardware ecosystem concept to support biomedical research; (2) explore pathways toward open-hardware ecosystems through four major areas, and (3) identify opportunities and future directions.


Assuntos
Pesquisa Biomédica , Animais , Ecossistema , Organismos Aquáticos , Modelos Animais
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