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- Snapshot isolation and isolation history challenge the analogy between mountains and islands used to understand endemismPublication . Flantua, Suzette G. A.; Payne, Davnah; Borregaard, Michael K.; Beierkuhnlein, Carl; Steinbauer, Manuel J.; Dullinger, Stefan; Essl, Franz; Irl, Severin D. H.; Kienle, David; Kreft, Holger; Lenzner, Bernd; Norder, Sietze; Rijsdijk, Kenneth F.; Rumpf, Sabine B.; Weigelt, Patrick; Field, RichardAIM: Mountains and islands are both well known for their high endemism. To explain this similarity, parallels have been drawn between the insularity of "true islands" (land surrounded by water) and the isolation of habitats within mountains (so-called "mountain islands"). However, parallels rarely go much beyond the observation that mountaintops are isolated from one another, as are true islands. Here, we challenge the analogy between mountains and true islands by re-evaluating the literature, focusing on isolation (the prime mechanism underlying species endemism by restricting gene flow) from a dynamic perspective over space and time. FRAMEWORK: We base our conceptualization of "isolation" on the arguments that no biological system is completely isolated; instead, isolation has multiple spatial and temporal dimensions relating to biological and environmental processes. We distinguish four key dimensions of isolation: (a) environmental difference from surroundings; (b) geographical distance to equivalent environment [points (a) and (b) are combined as "snapshot isolation"]; (c) continuity of isolation in space and time; and (d) total time over which isolation has been present [points (c) and (d) are combined as "isolation history"]. We evaluate the importance of each dimension in different types of mountains and true islands, demonstrating that substantial differences exist in the nature of isolation between and within each type. In particular, different types differ in their initial isolation and in the dynamic trajectories they follow, with distinct phases of varying isolation that interact with species traits over time to form present-day patterns of endemism. CONCLUSIONS: Our spatio-temporal definition of isolation suggests that the analogy between true islands and mountain islands masks important variation of isolation over long time-scales. Our understanding of endemism in isolated systems can be greatly enriched if the dynamic spatio-temporal dimensions of isolation enter models as explanatory variables and if these models account for the trajectories of the history of a system.
- Arthropod diversity in two Historic Gardens in the Azores, PortugalPublication . Arteaga, Alba; Malumbres-Olarte, Jagoba; Gabriel, Rosalina; Ros-Prieto, A.; Casimiro, Pedro; Fuentes-Sánchez, Ana; Albergaria, Isabel Soares de; Borges, Paulo A. V.The aim of our study was to characterise and compare the richness and composition of endemic, native (non-endemic) and introduced arthropod assemblages of two Azorean Historic Gardens with contrasting plant species composition. We hypothesised that Faial Botanic Garden would hold higher arthropod diversity and abundance of native and endemic arthropod species due to its larger native plant community. Species were collected using several arthropod standardised techniques between April 2017 and June 2018. We used the alpha diversity metrics (Hill series) and the partitioning of total beta diversity (βtotal) into its replacement (βrepl) and richness (βrich) components, to analyse the adult and total arthropod community. The orders Araneae, Coleoptera and Hemiptera were also studied separately. Our results show that the number of exotic arthropod species exceeds the number of native and/or the endemic species in both gardens, but the arthropod community of Faial Botanic Garden exhibited a higher density of endemic and native species. Despite some minor exceptions, the geographic origins of plant communities largely influenced the arthropod species sampled in each garden. This study improves our knowledge about urban arthropod diversity in the Azores and shows how well-designed urban garden management and planning contribute to the conservation of native and endemic Azorean species.
- Impact of introduced nest predators on insular endemic birds : the case of the Azores Woodpigeon (Columba palumbus azorica)Publication . Lamelas-López, Lucas; Fontaine, Rémi; Borges, Paulo A. V.; Gonçalves, DavidNest predation is the main cause of reproductive failure in many bird species. Identification of predators is crucial to understand and interpret the factors that affect nest predation. Although nest predation is a natural top-down regulator of bird populations, its effect is usually more dramatic when introduced predators are involved, particularly in oceanic islands. In the Azores archipelago, the endemic Azores Woodpigeon (Columba palumbus azorica) is believed to be under high predation pressure. We used motion-triggered cameras to monitor nests of the Azores Woodpigeon on two islands of the archipelago (Pico and Terceira) in order to identify nest predators, quantify their impact on this bird and better understand the determinants of predation rates. We sampled 56 nests, during 569 camera trap days, obtaining around 125,000 photographic records. Two introduced predators were identified, black rat (on both islands) and feral cat (only on Terceira), both depredating eggs and chicks. Breeding success, calculated using the Mayfield method, was estimated at 19% on Pico and only 9% on Terceira. Overall, predation was the main cause of breeding failure. General linear models showed that predation rates are positively correlated to fruit availability and negatively correlated to elevation, human population density and adult Woodpigeon attendance at the nest. Edge distance, nest height or cover of trees did not affect predation. Camera traps also provided additional and useful information on predator behaviour when approaching a nest and on daily activity patterns of both adult Woodpigeon and nest predators.
- Modelling the distribution of Mustela nivalis and M. putorius in the Azores archipelago based on native and introduced rangesPublication . Lamelas-López, Lucas; Pardavila, Xose; Borges, Paulo A. V.; Reis, Margarida Santos; Amorim, Isabel R.; Santos, Maria J.The aims of this study were to predict the potential distribution of two introduced Mustelidae, Mustela nivalis and M. putorius in the Azores archipelago (Portugal), and evaluate the relative contribution of environmental factors from native and introduced ranges to predict species distribution ranges in oceanic islands. We developed two sets of Species Distribution Models using MaxEnt and distribution data from the native and introduced ranges of the species to project their potential distribution in the archipelago. We found differences in the predicted distributions for the models based on introduced and on native occurrences for both species, with different most important variables being selected. Climatic variables were most important for the introduced range models, while other groups of variables (i.e., human-disturbance) were included in the native-based models. Most of the islands of the Azorean archipelago were predicted to have suitable habitat for both species, even when not yet occupied. Our results showed that predicting the invaded range based on introduced range environmental conditions predicted a narrower range. These results highlight the difficulty to transfer models from native to introduced ranges across taxonomically related species, making it difficult to predict future invasions and range expansion.
- Pharmacological and Cosmeceutical Potential of Seaweed Beach-Casts of MacaronesiaPublication . Zárate, Rafael; Portillo, Eduardo; Teixidó, Sílvia; Carvalho, Miguel A. A. Pinheiro de; Nunes, Nuno; Ferraz, Sónia; Seca, Ana M. L.; Rosa, Gonçalo P.; Barreto, Maria do CarmoSeaweed beach-casts are a seasonal phenomenon that regularly deposits tons of algae biomass on beaches, which are usually disposed of in landfills. The present work aimed to contribute to the valorization of this biomass by studying bioactivities that reveal its potential in the pharmaceutical and/or cosmeceutical industries. Methanol and ethanol extracts and fractions from 15 beach-casts biomass were tested for a range of bioactivities. Eight of the most active samples exhibit IC50 values between 11.38 µg/mL and 19.28 µg/mL and selectivity indexes higher than 3.8, against NCI-H1299 (lung cancer) and T47D (breast cancer). Concerning antiaging potential, all the extracts tested presented UV protection, with SPF values above 30, like the standard sunscreen. Regarding aging-related enzymes, 24 samples were tyrosinase inhibitors exhibiting IC50 values from 9.01 µg/mL to 200.09 µg/mL. Eight extracts inhibited collagenase (IC50 < 248.76 µg/mL), two of them more actively than positive control EDTA (IC50 = 59.26 µg/mL). In addition to UV protection, the cumulative effect of antityrosinase and anticollagenase activities shown by the samples suggest that they may play a significant role in preventing skin photoaging. The results obtained demonstrate the high potential of beach-cast seaweed biomass as sources of cosmetic bioproducts with antiaging effects, and of selective cytotoxic metabolites.
- First record on mercury accumulation in mice brain living in active volcanic environments : a cytochemical approachPublication . Navarro-Sempere, Alicia; Segovia, Yolanda; Rodrigues, Armindo; Garcia, Patrícia; Camarinho, Ricardo; García, M.The health effects of mercury vapor exposure on the brain in volcanic areas have not been previously addressed in the literature. However, 10% of the worldwide population inhabits in the vicinity of an active volcano, which are natural sources of elemental mercury emission. To evaluate the presence of mercury compounds in the brain after chronic exposure to volcanogenic mercury vapor, a histochemical study, using autometallographic silver, was carried out to compare the brain of mice chronically exposed to an active volcanic environment (Furnas village, Azores, Portugal) with those not exposed (Rabo de Peixe village, Azores, Portugal). Results demonstrated several mercury deposits in blood vessels, white matter and some cells of the hippocampus in the brain of chronically exposed mice. Our results highlight that chronic exposure to an active volcanic environment results in brain mercury accumulation, raising an alert regarding potential human health risks. These findings support the hypothesis that mercury exposure can be a risk factor in causing neurodegenerative diseases in the inhabitants of volcanically active areas.
- Low-cost technology for fish monitoring applied to the fishing of two species of pacu in Amazonas, BrazilPublication . Lourenço, Igor Hister; Anjos, Marcelo Rodrigues dos; Barreiros, João P.The present study aimed to investigate the “pacu” species’ commercialized in the “Colônia dos Pescadores Z-31” in the municipality of Humaitá, Amazonas State, from May 2018 to April 2019. For this purpose, we developed a method for raising a diary database in the colony, obtaining variables such as production, effort, catch per unit effort (CPUE), fishing spots, amongst others. We have identified two species of “pacu” - Mylossoma aureum and M. duriventre - with productions of 10.5 and 9.5 tonnes respectively which generated an income of U$ 22,173.00. Captures occurred mostly randomly, due to the region’s fishing characteristics although the CPUE was higher when compared to bigger cities. We could also find evidence over their migratory cycles from a correlation between the catching sites and the period, where: i) during the falling water (May to July), the “pacus” start to leave the streams and concentrate in lakes; ii) during the dry season (August to October), the “pacus” perform a second migratory cycle, leaving streams and lakes and going to rivers; iii) finally, during the rising water, “pacus” once again move to small streams. The generated information can be used in fishing strategies in the region, reducing costs with inputs.
- Low-Density Cardoon (Cynara cardunculus L.) Particleboards Bound with Potato Starch-Based AdhesivePublication . Monteiro, Sandra; Nunes, Lina; Martins, Jorge; D. Magalhães, Fernão; Carvalho, LuísaIn the present work, and for the first time, totally biosourced low-density particleboards were produced using cardoon particles (a no added value by-product from the Portuguese cheese making industry), bound with a potato starch adhesive. Different starch/cardoon ratios (0.6, 0.8, 1 and 1.2) were tested and the effect of different bio-based additives (chitosan, wood fiber and glycerol) on the performance of the adhesive system was evaluated. The best result was obtained for a formulation with a starch/cardoon mass ratio of 0.8, a chitosan/starch mass ratio of 0.05 and a water/starch mass ratio of 1.75. The particleboards produced had a density of 323 kg·m⁻³, internal bond strength of 0.35 N·mm⁻² and thickness swelling of 15.2%. The values of density and internal bond strength meet the standard requirements of general-purpose lightweight boards for use in dry conditions according to CEN/TS 16368 specification. Moreover, the susceptibility of the formulations with best results was established against subterranean termites and one decay fungi.
- A metáfora da árvore e as suas implicações na Filosofia para CriançasPublication . Arruda, Diana Catarina Carvalho; Castro, Maria Gabriela Couto Teves de AzevedoA presente dissertação, desenvolvida no âmbito do Mestrado em Filosofia para Crianças surge integrada num trabalho desenvolvido com as crianças, em contexto de CATL “ Centro de Atividades de Tempos Livres”, da Casa de Povo de Santo António, mais precisamente, na criação de um “cantinho de pensamento” – intitulado «O Jardim da Filosofia». Ali foi pintada, na parede, uma árvore que representa, metaforicamente, o conhecimento adquirido pelas crianças ao longo da sua participação nos trabalhos de jardinagem do pensar - um conhecimento que vai dando frutos através das experiências vividas e das competências adquiridas. Como qualquer planta, esta árvore precisa de ser regada e adubada para que possa dar os frutos indispensáveis ao desenvolvimento de um pensamento que se quer pertença de futuros cidadãos ativos numa sociedade que se quer democrática e participativa e dialógica, o que nos remete para a importância da (CIF) Comunidade de Investigação Filosófica. Neste sentido, para justificar o tema da tese, relembramos a famosa frase “Penso, logo existo” (ego cogito, ergo sum) de Descartes, em o Discurso do Método, nos Princípios da Filosofia e nas Meditações sobre a Filosofia Primeira., onde o filósofo francês eleva o pensar, cogito, a fundamento e base de todo o conhecimento verdadeiro. A árvore como metáfora filosófica e as suas implicações na filosofia para crianças vai ao encontro da famosa metáfora da árvore exposta por René Descartes, na carta ao tradutor da obra Princípios da Filosofia. De modo a analisar a metáfora da árvore passamos por Paul Ricoeur e pela análise do que é uma metáfora. E porque esta é uma dissertação, em Filosofia para Crianças, elaborada pensando nas crianças do CATL, abordamos alguns dos autores que de certa forma influenciaram Mathew Lipman no brotar desta área filosófica: Jean Jacques Rousseau, John Dewey, Paulo Freire e Jean Piaget. Por último, salientamos a importância do programa de Filosofia para Crianças segundo Mathew Lipman. Terminamos este trabalho com uma reflexão final que entrelaça os conhecimentos alcançados em todos os capítulos anteriores.