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1-Methyl-7-(4-nitrophenyl)-3-phenyl- pyrazolo[3,4-b]pyrrolo[3,4-d]pyridine- 6,8(3H,7H)-dione
(2008) Sabino, José Ricardo; Oliveira, Cecília Maria Alves de; Fraga, Carlos Alberto Manssour; Barreiro, Eliezer Jesus de Lacerda; Oliveira, Valéria de; Menegatti, Ricardo
A glyphosate-based herbicide induces histomorphological and protein expression changes in the liver of the female guppy Poecilia reticulata
(2017) Santos, Ana Paula Rezende dos; Rocha, Thiago Lopes; Borges, Clayton Luiz; Bailão, Alexandre Melo; Soares, Célia Maria de Almeida; Saboia-Morais, Simone Maria Teixeira de
Glyphosate-based herbicides (GBH) are among the most common herbicides found in aquatic systems, but limited data are available about their mode of action and hepatotoxicity in fish. This study investigated the hepatotoxicity induced by GBH in the guppy Poecilia reticulata using a histopathological assessment associated with a proteomic approach. Guppies were exposed to GBH for 24 h at 1.8 mg of glyphosate L−1, corresponding to 50% of the LC50, 96 h. The results indicate that the GBH at 1.8 mg of glyphosate L−1 induce the development of hepatic damage in P. reticulata, which is exposure-time dependent. The histopathological indexes demonstrate that GBH cause inflammatory, regressive, vascular and progressive disorders in the liver of guppies. Using 2D gel electrophoresis associated with mass spectrometry, 18 proteins that changed by GBH were identified and were related to the cellular structure, motility and transport, energy metabolism and apoptosis. The results show that the acute exposure to GBH causes hepatic histopathological damage related to protein expression profile changes in P. reticulata, indicating that a histopathological assessment associated with a proteomic analysis provides a valuable approach to assess the toxic effects of GBH in sentinel fish species.
A1 noradrenergic neurons lesions reduce natriuresis and hypertensive responses to hypernatremia in rats
(2013-09) Silva, Elaine Fernanda da; Oliveira, André Henrique Freiria de; Custódio, Carlos Henrique Xavier; Ghedini, Paulo César; Bataus, Luiz Artur Mendes; Colombari, Eduardo; Castro, Carlos Henrique de; Colugnati, Diego Basile; Rosa, Daniel Alves; Cravo, Sergio Luiz Domingues; Pedrino, Gustavo Rodrigues
Noradrenergic neurons in the caudal ventrolateral medulla (CVLM; A1 group) contribute to cardiovascular regulation. The present study assessed whether specific lesions in the A1 group altered the cardiovascular responses that were evoked by hypertonic saline (HS) infusion in non-anesthetized rats. Male Wistar rats (280–340 g) received nanoinjections of antidopamine-b-hydroxylase-saporin (A1 lesion, 0.105 ng.nL 21 ) or free saporin (sham, 0.021 ng.nL 21 ) into their CVLMs. Two weeks later, the rats were anesthetized (2% halothane in O 2 ) and their femoral artery and vein were catheterized and led to exit subcutaneously between the scapulae. On the following day, the animals were submitted to HS infusion (3 M NaCl, 1.8 ml N kg 21 , b.wt., for longer than 1 min). In the sham-group (n = 8), HS induced a sustained pressor response (DMAP: 3563.6 and 1161.8 mmHg, for 10 and 90 min after HS infusion, respectively; P,0.05 vs. baseline). Ten min after HS infusion, the pressor responses of the anti-DbH-saporin-treated rats (n = 11)were significantly smaller(DMAP: 1861.4 mmHg; P,0.05 vs. baseline and vs. sham group), and at 90 min, their blood pressures reached baseline values (261.6 mmHg). Compared to the sham group, the natriuresis that was induced by HS was reduced in the lesioned group 60 min after the challenge (19665.5 mM vs. 26267.6 mM, respectively; P,0.05). In addition, A1-lesioned rats excreted only 47% of their sodium 90 min after HS infusion, while sham animals excreted 80% of their sodium. Immunohistochemical analysis confirmed a substantial destruction of the A1 cell group in the CVLM of rats that had been nanoinjected withanti-DbH- saporin. These results suggest that medullary noradrenergic A1 neurons are involved in the excitatory neural pathway that regulates hypertensive and natriuretic responses to acute changes in the composition of body fluid.
A2 noradrenergic lesions prevent renal sympathoinhibition induced by hypernatremia in rats
(2012-05) Pedrino, Gustavo Rodrigues; Oliveira, André Henrique Freiria de; Colombari, Débora Simões Almeida; Rosa, Daniel Alves; Cravo, Sergio Luiz Domingues
Renal vasodilation and sympathoinhibition are recognized responses induced by hypernatremia, but the central neural pathways underlying such responses are not yet entirely understood. Several findings suggest that A2 noradrenergic neurons, which are found in the nucleus of the solitary tract (NTS), play a role in the pathways that contribute to body fluid homeostasis and cardiovascular regulation. The purpose of this study was to determine the effects of selective lesions of A2 neurons on the renal vasodilation and sympathoinhibition induced by hypertonic saline (HS) infusion. Male Wistar rats (280– 350 g) received an injection into the NTS of anti-dopamine-beta-hydroxylase-saporin (A2 lesion; 6.3 ng in 60 nl; n = 6) or free saporin (sham; 1.3 ng in 60 nl; n = 7). Two weeks later, the rats were anesthetized (urethane 1.2 g?kg 21 b.wt., i.v.) and the blood pressure, renal blood flow (RBF), renal vascular conductance (RVC) and renal sympathetic nerve activity (RSNA) were recorded. In sham rats, the HS infusion (3 M NaCl, 1.8 ml?kg 21 b.wt., i.v.) induced transient hypertension (peak at 10 min after HS; 962.7 mmHg) and increases in the RBF and RVC (14167.9% and 14067.9% of baseline at 60 min after HS, respectively). HS infusion also decreased the RSNA (24565.0% at 10 min after HS) throughout the experimental period. In the A2-lesioned rats, the HS infusion induced transient hypertension (661.4 mmHg at 10 min after HS), as well as increased RBF and RVC (13365.2% and 13466.9% of baseline at 60 min after HS, respectively). However, in these rats, the HS failed to reduce the RSNA (11563.1% at 10 min after HS). The extent of the catecholaminergic lesions was confirmed by immunocytochemistry. These results suggest that A2 noradrenergic neurons are components of the neural pathways regulating the composition of the extracellular fluid compartment and are selectively involved in hypernatremia-induced sympathoinhibition.
Uma abordagem normativa dos resíduos sólidos de saúde e a questão ambiental
(2009-06-16) Vilela-Ribeiro, Eveline Borges; Costa, Lorenna Silva Oliveira; Lima-Ribeiro, Matheus de Souza; Sousa, Maria Helena de
A special class of waste generated by man refers to Health Solid Waste (HSW), in general known as “hospitalar waste”, being that produced in health unities, consisting of common waste, infectious waste or with biological risk, and special waste. However, the final destination of HSW is a broad problem and involves a politic, economic, ethical and environmental discussion. So, is important to know the rules aplicable in the country about how the health institutions may proceed in the collection, selection and storage of HSW, and for this, initially is held an exposition about the HSW and its relation with environment. Then, a regulations review is done, approaching the main standards of the environmental management agencies, and that regulatory and licensing of health institutions too.
Absence of antimutagenicity of Cochlospermum regium ( Mart and Schr.) Pilger 1924 by micronucleus test in mice
(2008) Bezerra, Laryssa Silva de Andrade; Santos, D. B.; Castro, D. B.; Guillo, Lidia Andreu; Lee, Chen Chen
Cochlospermum regium (Mart. and Schr.) Pilger, popularly known as “algodãozinho do campo”, is a medicinal plant that grows in the Cerrado of Brazil. This plant has been used in traditional medicine against various diseases such as leucorrhoea, gastritis and ulcers. It has also been effective in treating skin problems like pimples, boils and blotches. In the present study, the in vivo antimutagenicity of aqueous extract of C. regium was evaluated. The Micronucleus Test was performed in polychromatic erythrocytes from Swiss male mice treated with one of the four doses of extract of the plant (19, 38, 76 and 114 mg.kg –1 body weight), administered by intraperitonial injection (i.p.) simultaneously with cy- clophosphamide (24 mg.kg –1 b.w.) or mitomycin C (4 mg.kg –1 b.w.). The cytotoxicity was evaluated by polychromatic and normochromatic erythrocytes ratio (PCE/NCE). The results showed no significant reduction of the micronucleated polychromatic erythrocytes frequency (P > 0.05). In conclusion, the data indicate that C. regium roots aqueous extract, for the conditions used, did not exhibit the antimutagenic effect.
Abundance distribution of common and rare plant species of Brazilian savannas along a seasonality gradient
(Sociedade Botânica do Brasil, 2010-06) Silva, Igor Aurélio; Cianciaruso, Marcus Vinicius; Batalha, Marco Antônio
We examined the species abundance distribution (SAD) of plant communities in: (1) a wet grassland, waterlogged throughout most of the year; (2) a seasonal savanna, with an annual dry season; and (3) a hyperseasonal savanna, with alternating drought and waterlogging over the year. We searched for differences in the abundance distributions of all species, as well as of the common and rare species. We tested whether the SADs fitted the lognormal, log-series, power fraction, and random assortment models. We found that environmental constraints may reduce the evenness of plant communities and change the SADs in savannas. We observed a lognormal abundance distribution in the wet grassland and a random abundance distribution in the hyperseasonal cerrado. The SAD of the seasonal savanna did not follow any model. The common species in the three communities were better fitted by the lognormal model. The rare species in the wet grassland and the hyperseasonal cerrado were better fi tted by the random assortment model. The SAD of the rare species of the seasonal savanna did not follow any model. Seasonality seems to modify the lognormal distribution of the overall plant community, generating abundance distributions indistinguishable from random. However, differential community structuring between common and rare species may not be affected by seasonality. The different signatures of the abundance distributions of common and rare plants indicate that composite models are better predictors for SADs in savannas
Abundance of epigaeic arthropods in a brazilian savanna under different fire frequencies
(Sociedade Brasileira de Zoologia, 2010-10) Prado, Marcio Uehara; Bello, Ayr de Moura; Fernandes, Juliana de Oliveira; Santos, Adalberto José dos; Silva, Igor Aurélio da; Cianciaruso, Marcus Vinicius
Fire is a major determinant of structure and dynamics in savannas, and the rapid increase of human activities in this biome has changed the natural burning regime. The effects of fire on the fauna of the cerrado (Brazilian savanna) are still poorly understood, and studies comparing sites frequently and infrequently burned are scarce. In this study, the abundance of epigaeic arthropod orders and trophic guilds was assessed in cerrado sites located in the Brazilian Central Plateau that were subjected to three burning frequencies: frequent (HighFi), intermediary (MidFi), and infrequent (LowFi). In general, we found a positive relationship between the abundance of epigaeic arthropods and fire frequency. When arthropods were analyzed by orders, the abundance of Collembola and Orthoptera was lower in the LowFi site, while for Hemiptera, it was higher in the MidFi site. No significant differences were found for Hymenoptera, Coleoptera, and Araneae. The abundance of detritivores and herbivores decreased from HighFi to LowFi, but did not change significantly for omnivores and predators. These results indicate that some arthropod groups may not only be resilient to fire effects, but actually might benefit from fire effects in the cerrado. Characterizing arthropod responses to burning frequency at high taxonomic or functional levels is important for applied studies. Based on the results of the current study, springtails and ants seem to be particularly appropriate focal groups for further exploratory studies on the effects of fire at the species level.
Accommodating species climate-forced dispersal and uncertainties in spatial conservation planning
(Public Library of Science, 2013-01) Lemes, Priscila; Loyola, Rafael Dias
Spatial conservation prioritization should seek to anticipate climate change impacts on biodiversity and to mitigate these impacts through the development of dynamic conservation plans. Here, we defined spatial priorities for the conservation of amphibians inhabiting the Atlantic Forest Biodiversity Hotspot that overcome the likely impacts of climate change on the distribution of this imperiled fauna. First, we built ecological niche models (ENMs) for 431 amphibian species both for current time and for the mid-point of a 30-year period spanning 2071–2099 (i.e. 2080). For modeling species’ niches, we combined six modeling methods and three different climate models. We also quantified and mapped model uncertainties. Our consensus models forecasted range shifts that culminate with high species richness in central and eastern Atlantic Forest, both for current time and for 2080. Most species had a significant range contraction (up to 72%) and 12% of species were projected to be regionally extinct. Most species would need to disperse because suitable climatic sites will change. Therefore, we identified a network of priority sites for conservation that minimizes the distance a given species would need to disperse because of changes in future habitat suitability (i.e. climate-forced dispersal) as well as uncertainties associated to ENMs. This network also maximized complementary species representation across currently established protected areas. Priority sites already include possible dispersal corridors linking current and future suitable habitats for amphibians. Although we used the a top-ranked Biodiversity Hotspot and amphibians as a case study for illustrating our approach, our study may help developing more effective conservation strategies under climate change, especially when applied at different spatial scales, geographic regions, and taxonomic groups.
Acetone extract from Streptoverticillium sp., a bacterium isolated from Brazilian cerrado soil, induces anti-infl ammatory activity in mice
(2013-06) Cruz, Rodrigo Barbosa da; Carvalho, Pablinny Moreira Galdino de; Penna, Karlla Greick Batista Dias; Costa, Elson Alves; Bataus, Luiz Artur Mendes
The Streptoverticillium sp. Z1 is an actinomycete isolated from the soil under Cerrado vegetation, the extract of this strain was investigated in nociceptive and infl ammatory models. The Streptoverticillium extract (ExS) 50 and 100 mg/kg (s.c.) produced a signifi cant inhibition of acetic acid-induced abdominal writhings thereby demonstrating an anti-nociceptive effect. In the tail fl ick test the ExS (s.c.) was inactive. This result implited that ExS does not contain opioid-like compounds with central analgesic properties. In the infl ammatory models, ExS 100 and 200 mg/kg (s.c.) were able to inhibit the croton oil-induced ear edema and, ExS 200 and 500 mg/kg (s.c.) inhibited the leukocyte migration on the carrageenan-induced peritonitis. The phospholipase A 2 enzymatic assay showed that the anti-infl ammatory activity of ExS was not due to direct effect on phospholipase A 2 activity. These data suggest that Streptoverticillium sp. produces metabolites with anti- infl ammatory effect and that these metabolites are unable to directly inhibit phospholipase A 2 enzyme.
Achieving global biodiversity goals by 2050 requires urgent and integrated actions
(2022) Leadley, Paul; Gonzalez, Andrew; Obura, David; Krug, Cornelia B.; Londoño Murcia, Maria Cecilia; Millette, Katie L.; Radulovici, Adriana; Rankovic, Aleksandar; Shannon, Lynne J.; Archer, Emma; Loyola, Rafael Dias
Acoustic communication in two species of the Hypsiboas albopunctatus group (Anura: Hylidae) in sympatry and allopatry
(2016-04) Vieira, Raísa Romênia Silva; Alves, Ruy José Válka; Batista, Vinícius Guerra; Bastos, Rogério Pereira
Tropical anuran communities are very diverse. Nevertheless, much of their ecological and historical processes remain unknown. Bioacoustical studies are important to help to solve these puzzles. In the present study we examined the effect of environmental (air temperature and humidity) and morphological (body size) attributes on the acoustic parameters of two frogs of the Hypsiboas albopunctatus species group (H. albopunctatus and H. paranaiba) living in sympatry and allopatry in the Brazilian cerrado. We also investigated if the presence of one species influences the spatial distribution or vocal behaviour of the other. We found H. albopunctatus and H. paranaiba males emitting advertisement and aggressive calls in sympatry and allopatry. Although the calling behavior of H. paranaiba did not differ in sympatry and allopatry, differences were noted for H. albopunctatus. Bioacoustics is the main form of communication in anurans, and is one of the best ways to discriminate among species. Variations in the calling behavior of males and what drives these variations in both species is central to better understand the processes of specific recognition and female attraction.
Acoustic repertoire of Barycholos ternetzi (Anura: Strabomantidae) in central Brazil
(Brazilian Society of Herpetology, 2012-08) Lemes, Priscila; Tessarolo, Geiziane; Morais, Alessandro Ribeiro de; Bastos, Rogério Pereira
Barycholos ternetzi is an anuran species from the Brazilian Cerrado which can be found in gallery forests and Cerrado sensu strictu. Currently, the only available information about the natural history of B. ternetzi is a previous description of its advertisement call. Herein, we studied the vocal repertoire of this species in October 2009 at Floresta Nacional de Silvânia, Goiás state, Central Brazil. We ecognized four distinct vocalizations, of which the advertisement call was the most common. The aggressive call was emitted in response to a neighbor male, while the distress and fighting calls were emitted, respectively, when the male was caught or during physical interactions. We also observed that the dominant frequency was influenced by call duration and body size, while the call duration and repetition rate were influenced by air temperature. Furthermore, we observed that the chorus size influenced the repetition rate of the advertisement call of B. ternetzi.
Acoustic variability among male gladiator frogs, Boana goiana (Lutz, 1968) (Anura: Hylidae): an 18-year analysis across several reproductive seasons
(2020) Andreani, Tainã Lucas; Bastos, Rogério Pereira; Dias, Tailise Marques; Prado, Cynthia Peralta de Almeida; Morais, Alessandro Ribeiro de
Male anurans emit different call types in specific social contexts. Such calls represent a communication pathway for species recognition, mate choice, and male-male competition mediation. The acoustic parameters of these calls can be under directional and/or stabilizing selection due to female choice, which influences intra- and inter-individual call variation. Herein, we investigated the inter-year variation of the advertisement and aggressive calls of the gladiator frog Boana goiana, analysing a temporal series encompassing 18 years of sampling (1996-2014). We measured and analysed the following acoustic parameters: call duration, call repetition rate, number of pulses, pulse duration, pulse repetition rate, and dominant frequency. For both call types, the dominant frequency was classified as a static parameter (CVintra < 5%), while call duration was a dynamic parameter (CVintra > 12%). The advertisement call of B. goiana presents the attributes that could allow individual recognition in the chorus, and we suggest that the aggressive calls might also be important for the individual recognition process. Pulse duration of the advertisement and aggressive calls decreased over the years, as well as the repetition rate of the aggressive calls, which could be related to male body size decrease over the years probably related to habitat alteration. This study provides data on the variation of anuran acoustic features over the longest time span ever analysed. Such studies are less invasive and useful for conservation purposes, since they can detect changes in the reproductive behaviour of populations that might be under environmental modification pressure.
Acute toxicity of Brosimum gaudichaudii Trécul. root extract in mice: determination of both approximate and median lethal doses
(2008-12) Cunha, Luiz Carlos da; Paula, José Realino de; Sá, Vinicius Augusto de; Amorim, Marcos Evaristo da Paixão e; Barros, Isabel Cristina Medeiros; Brito, Luiz Augusto Batista; Silveira, Nusa da
The Brosimum gaudichaudii Trécul. (BG) Moraceae, with a high frequency in regions of the Brazilian cerrado (shrubland) and popularly known as “mamacadela”, holds photosensitizing furocoumarins. The BG’s main therapeutic use is the treatment of vitiligo, a skin depigmentation disease that takes hold of approximately 1-2 % of the world population. There is one product on the marketplace (Viticromin ® ), for which there is no scientifi c research available about its experimental toxicity, in spite of its proven clinical effi cacy. Therefore, the development of acute pre-clinical toxicity trials has been proposed (approximate lethal dose, ALD, and median lethal dose, LD50) of the BG root exsudate in laboratory animals. Male, albino mice weighing between 25 and 30 g, in good sanitation conditions have been used. The mice received water and food ad libitum. The BG powder was mixed in 0.9% saline solution and 0.5% cremophor and was administered po and ip. The LD50 was obtained through the Lichtfi eld and Wilcoxon (1949) method. A public domain software was used for the calculations. Ten mice/dose were used - 6 groups for each administration via, including the control group - and the number of deaths within up to 14 days was considered; the control group received an emulsion made up by 0.9 saline solution and 0.5% cremophor. Before establishing the LD50 and aiming at reducing the number of animals used, the DLA was determined when 1 animal per dose was used (the next dose always 50% higher than the previous dose), until identifying the dose that led to the death of 1 animal. Thus, the DLA po was 3750 mg/kg and the DLA ip, 2920 mg/kg. The LD50 po was 3517.54 mg/ kg and the LD50 ip was 2871.76 mg/kg. The product was considered as of being of low toxicity, taking into account only the single dose acute toxicity.
Adaptation of the gill epithelium of an euryhaline fish, the guppy (Poecilia vivipara), to freshwater
(2011) Sabóia-Morais, Simone Maria Teixeira de; Saldiva, Paulo Hilário Nascimento; Silva, José Roberto Machado Cunha da; Yamada, Áureo Tatsumi; Aloia, Thiago Pinheiro Arrais; Blazquez, Francisco Javier Hernandez
O peixe eurihalino sul-americano Poecilia vivipara (BLOCH; SNEIDER, 1801), o guppy, é encontrado tanto em estuários quanto em águas de rios, o que sugere uma alta adaptabilidade aos diferentes ambientes de salinidade. Neste trabalho, estudamos a adaptação do epitélio interlamelar, do arco e do rastelo das brânquias dos peixes de estuário de água doce. Os resultados revelam que o epitélio branquial de Poecilia vivipara pode ajustar-se à água doce, diminuindo a proporção volumétrica (PV) de células mucosas do epitélio interlamelar e aumentando a PV de células clorídricas. No entanto, não houve nenhuma evidência de alteração morfológica semelhante na região do rastelo branquial. O epitélio do rastelo branquial parece ser parte de um compartimento diferente que é menos sensível a variações de salinidade.
Additions to the taxonomy of the Hypolepis rugosula complex (Dennstaedtiaceae) in Africa: corrections, two new subspecies and new distribution maps
(2016) Schwartsburd, Pedro Bond; Oliveira, Marcelo H.; Joner, Daiany Caroline; Loyola, Rafael Dias; Prado, Jefferson
This paper presents complementary data to the recently published taxonomic treatment of the Hypolepis rugosula complex around the world, with special reference to Africa and surrounding islands. Here we present a new subspecies from South Africa (H. rugosula subsp. rouxii) and another from Bioko, Equatorial Guinea (H. rugosula subsp. formosa). We present an updated nomenclatural paragraph for H. rugosula subsp. africana, along with the lectotypification of one heterotypic synonym (Phegopteris boryana) and comments regarding similar but unrelated names (e.g. Aspidium boryanum). We also transfer H. goetzei to the synonymy of H. rugosula subsp. pichi-sermolliana, choosing a new lectotype for it. The population of H. rugosula from South Africa (= subsp. rouxii) is likely to be the source population for populations of Saint Helena (= subsp. viscida) and Ascension Island (= subsp. brownseyana), based on morphological comparisons and on the anticlockwise wind direction. Based on the latitude, H. rugosula subsp. formosa would be expected to be found only at the higher elevations in Bioko (above 2,000 m a.s.l.), but it is also found at mid-elevations (ca 700 m a.s.l.). Apparently, this is a natural pattern of islands and is increased by deforestation. We also offer further taxonomic and ecological comments on the complex, additional examined specimens and maps of distribution in Africa with real occurrences and modelled distributions. The modelled distribution map (based on climatic data) confirms the disjunction of the African subspecies.
Additive effects of climate change and human hunting explain population decline and extinction in cave bears
(2019) Mondanaro, Alessandro; Di Febbraro, Mirko; Melchionna, Marina; Carotenuto, Francesco; Castiglione, Silvia; Serio, Carmela; Danisi, Simone; Rook, Lorenzo; Diniz Filho, José Alexandre Felizola; Raia, Pasquale
Cave bears (Ursus spelaeus) are an iconic component of the European late Quaternary Ice Age megafauna. Recent demographic analyses based on cave bear mtDNA sequences and refined radiocarbon dating indicate that cave bear population size and genetic diversity started to decline some 50 kilo years ago (kya). Hence, neither the coldest phase of the last glaciation (started some 24 kya), nor the colonization of Europe by Palaeolithic hunters (started some 45 kya) coincides with the beginning of population decline. Here, we reconstructed cave bear climatic niche evolution through time. Then, we performed spatially explicit population viability analyses to assess cave bear demographics through time in response to climatic changes, human effects on bear survival and their combination. We found that climate change was responsible for a 10-fold decrease in cave bear population size after 40 kya. However, climate change on its own could not explain U. spelaeus extinction at 24 kya. Additional negative effects consistent with human population expansion are required to explain both U. spelaeus' retreat from eastern Europe since 40 kya and its final extinction.
Adjacency and area explain species bioregional shifts in neotropical palms
(2019) Freitas, Cíntia Gomes de; Bacon, Christine; Souza Neto, Advaldo Carlos de; Collevatti, Rosane Garcia
Environmental and geographical variables are known drivers of community assembly, however their influence on phylogenetic structure and phylogenetic beta diversity of lineages within different bioregions is not well-understood. Using Neotropical palms as a model, we investigate how environmental and geographical variables affect the assembly of lineages into bioregions across an evolutionary time scale. We also determine lineage shifts between tropical (TRF) and non-tropical (non-TRF) forests. Our results identify that distance and area explain phylogenetic dissimilarity among bioregions. Lineages in smaller bioregions are a subset of larger bioregions and contribute significantly to the nestedness component of phylogenetic dissimilarity, here interpreted as evidence for a bioregional shift. We found a significant tendency of habitat shifts occurring preferentially between TRF and non-TRF bioregions (31 shifts) than from non-TRF to TRF (24) or from TRF to TRF (11) and non-TRF to non-TRF (9). Our results also present cases where low dissimilarity is found between TRF and non-TRF bioregions. Most bioregions showed phylogenetic clustering and larger bioregions tended to be more clustered than smaller ones, with a higher species turnover component of phylogenetic dissimilarity. However, phylogenetic structure did not differ between TRF and non-TRF bioregions and diversification rates were higher in only two lineages, Attaleinae and Bactridinae, which are widespread and overabundant in both TRF and non-TRF bioregions. Area and distance significantly affected Neotropical palm community assembly and contributed more than environmental variables. Despite palms being emblematic humid forest elements, we found multiple shifts from humid to dry bioregions, showing that palms are also important components of these environments.
Advancing impact evaluation in applied limnology
(2019) Ribas, Luiz Guilherme dos Santos; Padial, André Andrian; Bini, Luis Mauricio
Accurate impact evaluations of different interventions are paramount in environmental sciences. In this context, the main challenge is to identify causal relationships to understand how different interventions affect the systems of interest. For this task, the counterfactual thinking can be used to estimate the impacts of interventions on the real scale of the problem using observational data. By definition, counterfactuals are states contrary to facts. In the context of interventions, they are the states of the units of analysis in the absence of intervention. This approach allows one to estimate the impact more accurately by comparing the differences between factual and counterfactual states. In this essay, we present some basic elements of the counterfactual thinking and discuss how it, based on experiences in other areas (e.g., medicine and economics), may be useful for the research of complex problems in aquatic ecology.

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