55 research outputs found

    ECOLOGIA COMPORTAMENTAL EVOLUTIVA APLICADA A PEIXES DE RIACHO

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    ObservaçÔes diretas em campo constituem uma importante fonte de informaçÔes sobre a história natural e o comportamento de peixes de riacho. Contudo, tais observaçÔes diretas podem ser insuficientes para permitir conclusÔes robustas sobre as causas dos fenÎmenos biológicos envolvidos, jå que dados observacionais frequentemente falham em demonstrar de forma contundente relaçÔes de causa e efeito. Neste estudo nós trazemos conceitos necessårios para a formulação de hipóteses a partir de uma versão derivada da História Natural e da Etologia, a Ecologia Comportamental Evolutiva. Essaperspectiva permite anålises do contexto evolutivo e do valor adaptativo dos padrÔes comportamentais observados, e serve de base para novas hipóteses que podem ser aplicadas a muitos grupos de organismos. ObservaçÔes e experimentos envolvendo peixes de riacho originaram e deram subsídio a muitas teorias sobre a evolução de comportamentos e de características morfológicas peculiares que são amplamente debatidas pela comunidade científica. Após apresentar os conceitos chaves, nós trazemos alguns exemplos de programas de pesquisas com peixes que culminaram na formulação de importantes teorias, onde cientistas aproveitaram as oportunidades que os peixes de riacho oferecem e conduziramobservaçÔes, amostragens e experimentos controlados em campo e laboratório. Descrevemos nosso programa de pesquisas, que tem uma espécie amazÎnica de peixe de riacho (Crenuchus spilurus) como organismo modelo. Ao final, advogamos pela pluralidade de métodos e anålises no estudo da Ecologia Comportamental Evolutiva de peixes de riacho.BEHAVIORAL EVOLUTIONARY ECOLOGY - WITH APPLICATIONS TO FRESHWATER STREAM FISH: Direct field observation constitutes an important source of information on life history and behavior ofstream fish. Unfortunately, information gathered from direct field observations are often limited and thus may fail to provide robust testing for the causation of biological phenomena. Here, we bring concepts that form the theoretical foundation necessary for raising hypotheses in Evolutionary Behavioral Ecology,a study area directly derived from natural history and ethology that directly incorporates evolutionary processes and the adaptative value of behavioral patterns observed. This perspective allows the analysisof the evolutionary context and the adaptive value of observed behavioral patterns, and serves as the basis for new hypotheses that can be applied to many groups of organisms. Using this framework, field observations and experiments encompassing freshwater stream fish have subsidized many theories on the evolution of behavioral and morphological traits that are widespread debated by scientific community. After presenting the main key concepts, we bring some examples of research programs with freshwater fish that culminated in the formulation of important theories and where scientists took advantage of the opportunities provided by stream fish to conduct observations, samplings and controlled experiments both in the field and in captivity. We also describe our own research program, which uses an Amazonian freshwater stream fish (Crenuchus spilurus) as a model organism. By doing so, we advocate for the use of several methods and analyses for the study of Evolutionary Behavioral Ecology of freshwater stream fish

    3D biocomposites comprising marine collagen and silica-based materials inspired on the composition of marine sponge skeletons envisaging bone tissue regeneration

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    Ocean resources are a priceless repository of unique species and bioactive compounds with denouement properties that can be used in the fabrication of advanced biomaterials as new templates for supporting the cell culture envisaging tissue engineering approaches. The collagen of marine origin can be sustainably isolated from the underrated fish processing industry by-products, while silica and related materials can be found in the spicules of marine sponges and diatoms frustules. Aiming to address the potential of biomaterials composed from marine collagen and silica-based materials in the context of bone regeneration, four different 3D porous structure formulations (COL, COL:BG, COL:D.E, and COL:BS) were fabricated by freeze-drying. The skins of Atlantic cod (Gadus morhua) were used as raw materials for the collagen (COL) isolation, which was successfully characterized by SDS-PAGE, FTIR, CD, and amino acid analyses, and identified as a type I collagen, produced with a 1.5% yield and a preserved characteristic triple helix conformation. Bioactive glass 45S5 bioglass¼ (BG), diatomaceous earth (D.E.) powder, and biosilica (BS) isolated from the Axinella infundibuliformis sponge were chosen as silica-based materials, which were obtained as microparticles and characterized by distinct morphological features. The biomaterials revealed microporous structures, showing a porosity higher than 85%, a mean pore size range of 138Ăą 315 ”m depending on their composition, with 70% interconnectivity which can be favorable for cell migration and ensure the needed nutrient supply. In vitro, biological assays were conducted by culturing L929 fibroblast-like cells, which confirmed not only the non-toxic nature of the developed biomaterials but also their capability to support cell adhesion and proliferation, particularly the COL:BS biomaterials, as observed by calcein-AM staining upon seven days of culture. Moreover, phalloidin and DAPI staining revealed well-spread cells, populating the entire construct. This study established marine collagen/silica biocomposites as potential scaffolds for tissue engineering, setting the basis for future studies, particularly envisaging the regeneration of non-load-bearing bone tissues.This research was funded by European Union’s Horizon 2020 Framework Programme for Research and Innovation under the projects SponGES (H2020-BG-01-2015-679849)

    The 2024 Outline of Fungi and fungus-like taxa

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    With the simultaneous growth in interest from the mycological community to discover fungal species and classify them, there is also an important need to assemble all taxonomic information onto common platforms. Fungal classification is facing a rapidly evolving landscape and organizing genera into an appropriate taxonomic hierarchy is central to better structure a unified classification scheme and avoid incorrect taxonomic inferences. With this in mind, the Outlines of Fungi and fungus-like taxa (2020, 2022) were published as an open-source taxonomic scheme to assist mycologists to better understand the taxonomic position of species within the Fungal Kingdom as well as to improve the accuracy and consistency of our taxonomic language. In this paper, the third contribution to the series of Outline of Fungi and fungus-like taxa prepared by the Global Consortium for the Classification of Fungi and fungus-like taxa is published. The former is updated considering our previous reviews and the taxonomic changes based on recent taxonomic work. In addition, it is more comprehensive and derives more input and consensus from a larger number of mycologists worldwide. Apart from listing the position of a particular genus in a taxonomic level, nearly 1000 notes are provided for newly established genera and higher taxa introduced since 2022. The notes section emphasizes on recent findings with corresponding references, discusses background information to support the current taxonomic status and some controversial taxonomic issues are also highlighted. To elicit maximum taxonomic information, notes/taxa are linked to recognized databases such as Index Fungorum, Faces of Fungi, MycoBank and GenBank, Species Fungorum and others. A new feature includes links to Fungalpedia, offering notes in the Compendium of Fungi and fungus-like Organisms. When specific notes are not provided, links are available to webpages and relevant publications for genera or higher taxa to ease data accessibility. Following the recent synonymization of Caulochytriomycota under Chytridiomycota, with Caulochytriomycetes now classified as a class within the latter, based on formally described and currently accepted data, the Fungi comprises 19 Phyla, 83 classes, 1,220 families, 10,685 genera and ca 140,000 species. Of the genera, 39.5% are monotypic and this begs the question whether mycologists split genera unnecessarily or are we going to find other species in these genera as more parts of the world are surveyed? They are 433 speciose genera with more than 50 species. The document also highlights discussion of some important topics including number of genera categorized as incertae sedis status in higher level fungal classification. The number of species at the higher taxonomic level has always been a contentious issue especially when mycologists consider either a lumping or a splitting approach and herein we provide figures. Herein a summary of updates in the outline of Basidiomycota is provided with discussion on whether there are too many genera of Boletales, Ceratobasidiaceae, and speciose genera such as Colletotrichum. Specific case studies deal with Cortinarius, early diverging fungi, Glomeromycota, a diverse early divergent lineage of symbiotic fungi, Eurotiomycetes, marine fungi, Myxomycetes, Phyllosticta, Hymenochaetaceae and Polyporaceae and the longstanding practice of misapplying intercontinental conspecificity. The outline will aid to better stabilize fungal taxonomy and serves as a necessary tool for mycologists and other scientists interested in the classification of the Fungi

    Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

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    The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & NemĂ©sio 2007; Donegan 2008, 2009; NemĂ©sio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

    Pampean lizard assemblage from subtropical Brazil: a temporal analysis

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    The increasing human occupation of natural environments is one of the greatest threats to biodiversity. To mitigate the negative anthropogenic effects, it is necessary to understand the characteristics of natural populations and the natural history of species. A study was conducted with an assemblage of lizards from a disturbed area of the Pampa biome, from February 2001 to January 2004. The assemblage showed a unimodal seasonal pattern, with the recruitment period occurring during the warmer months. The captures were seasonal for two of the three monitored years, and concentrated within warmer months. The minimum temperature explained the number of catches for the assemblage as a whole. However, when the species were analyzed individually, the temperature only explained the seasonal occurrence of Teius oculatus. The abundance of species was significantly different in the third year of study for Cercosaura schreibersii and Ophiodes striatus. This latter species was no longer registered in the study area from May 2003 until the end of the study. Therefore, O. striatus may be more sensitive to environmental changes, considering the events of change in vegetation during the study. With frequent and increasing environmental disturbances, it is necessary to take conservation measures and encourage the increase of knowledge on Pampean lizards.O crescimento da ocupação humana sobre ambientes naturais Ă© uma das maiores ameaças Ă  biodiversidade. Para amenizar os efeitos negativos antropogĂȘnicos, Ă© necessĂĄrio entender as caracterĂ­sticas das populaçÔes naturais, e a histĂłria natural das espĂ©cies. Um estudo foi conduzido com uma assembeia de lagartos de uma ĂĄrea perturbada do Pampa, de fevereiro de 2002 a janeiro de 2004. A assembleia apresentou padrĂŁo sazonal unimodal, com recrutamento ocorrendo durante os meses mais quentes. As capturas foram sazonais durante dois dos trĂȘs anos monitorados, e concentradas nos meses mais quentes. A temperatura mĂ­nima explica o nĂșmero de capturas para a assembleia como um todo. Entretanto, quando as espĂ©cies foram analisadas individualmente, a variĂĄvel explica apenas a ocorrĂȘncia sazonal de Teius oculatus. A abundĂąncia das espĂ©cies foi significativamente distinta no terceiro ano de estudo para Cercosaura schreibersii e Ophiodes striatus. Essa Ășltima espĂ©cie nĂŁo teve mais registros na ĂĄrea de maio de 2003 atĂ© o final do estudo. Assim, O. striatus pode ser mais sensĂ­vel Ă s udanças abientais, considerando os eventos de udança na vegetação ocorridas durante o estudo. Com as frequentes e crescentes perturbaçÔes ambientais que o bioma vem sofrendo, sĂŁo necessĂĄrias açÔes de conservação, e dar suporte para o aumento do conhecimento dos lagartos pampeanos

    Amazonia Camtrap: a data set of mammal, bird, and reptile species recorded with camera traps in the Amazon forest.

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    Abstract : The Amazon forest has the highest biodiversity on Earth. However, information on Amazonian vertebrate diversity is still deficient and scatteredacross the published, peer-reviewed, and gray literature and in unpublishedraw data. Camera traps are an effective non-invasive method of surveying vertebrates, applicable to different scales of time and space. In this study, we organized and standardized camera trap records from different Amazonregions to compile the most extensive data set of inventories of mammal,bird, and reptile species ever assembled for the area. The complete data setcomprises 154,123 records of 317 species (185 birds, 119 mammals, and13 reptiles) gathered from surveys from the Amazonian portion of eightcountries (Brazil, Bolivia, Colombia, Ecuador, French Guiana, Peru,Suriname, and Venezuela). The most frequently recorded species per taxawere: mammals:Cuniculus paca (11,907 records); birds: Pauxi tuberosa (3713 records); and reptiles:Tupinambis teguixin(716 records). The infor-mation detailed in this data paper opens up opportunities for new ecological studies at different spatial and temporal scales, allowing for a moreaccurate evaluation of the effects of habitat loss, fragmentation, climatechange, and other human-mediated defaunation processes in one of themost important and threatened tropical environments in the world. The data set is not copyright restricted; please cite this data paper when usingits data in publications and we also request that researchers and educator sinform us of how they are using these data

    Intertidal life: field observations on the clingfish Gobiesox barbatulus in southeastern Brazil

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    The clingfish Gobiesox barbatulus shows nocturnal feeding activity, spending most part of the day stationary and adhered to the inferior part of stones. To feed, this species uses the sit-and-wait and particulate feeding tactics. It shows a carnivorous feeding habit mostly consuming small benthic crustaceans. It can move in two ways: (1) "stone-by-stone", sliding its ventral sucker disc across each stone and (2) "surf", when it takes advantage of the energy of the ebbing tide to quickly cross a distance up to four times its body length. Its reproductive season occurs between the end of spring and the beginning of summer, during which time it lays about 2,000 adhesive eggs of 1 mm each in a single layer under stones. It has more than one egg-laying session per reproductive season, therefore showing several different developmental stages. It performs fanning, mouthing and guarding of the eggs as forms of parental care. Data shown here also indicates that G. barbatulus has some shelter fidelity, being probably territorial
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