Biogeography of a fragmenting world

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Epiphytic bryophytes of Quercus forests in Central and North inland Iberian Peninsula

Diversity patterns are governed by a complex network of interacting factors. Studies directed to disentangle the most important factors affecting diversity have frequently shown divergent results, which has encouraged a rewarding debate about the relative importance of each factor. Scale dependency has been identified as a direct cause of at least part of such divergences. However, studies with spatially-explicit measurements at different scales are costly and therefore they are relatively scarce despite their importance. Here, we present a database to disentangle the cross-scale variation in the importance of factors affecting the diversity of epiphytic bryophyte communities in Quercus dominated forests (Quercus ilex L., Quercus pyrenaica Willd. and Quercus faginea Lam.) in the North-western region of the Iberian Peninsula. We provide speciesper- site abundance information with more than 9000 entries and an environmental table containing 20 in situ measured variables at three different scales (forest, stand, and sample). The database will help to advance the research of cross-scale effects of diversity patterns while at the same time providing valuable information on the distribution of a poorly known group of organisms.The fieldwork was funded by the Spanish Government through grants CGL2007-61389, CGL2010-15693 and CGL2011-28857. N.G.M. was supported by a PhD grant from the Spanish Ministry of Education (grant number AP2007-00905).Peer reviewe

Time, area and isolation: factors driving the diversification of Azorean arthropods

Copyright © 2008 The Authors. Journal compilation.Copyright © 2008 Blackwell Publishing.R. J. Whittaker et al. recently proposed a ‘general dynamic model of oceanic island biogeography’ (GDM), providing a general explanation of island biodiversity patterns by relating fundamental biogeographical processes – speciation, immigration, extinction – to area (A) and time (T; maximum island geological age). We adapt their model, which predicts a positive relationship with area combined with a humped relationship to time (designated the ATT2 model), to study the factors promoting diversification on the Azores for several arthropod groups

Global Distribution of COVID-19 Vaccine: Mine First

The COVID-19 (SARS-CoV-2) pandemic dealt a severe blow to society as a whole and required countries to confront a situation that exceeded the limits of their borders. In this paper, we analyze how these countries as well as supranational organizations responded to this unprepared global emergency. We also explore what alternative models have been proposed in the wake of this crisis and propose some changes—other ways of acting—so that in future pandemics or global emergencies, we can deal with the situation more effectively.MCIN/AEI PID2020-118729RB-I0

Evaluating the performance of species richness estimators: sensitivity to sample grain size

Copyright © 2006 British Ecological Society.1. Fifteen species richness estimators (three asymptotic based on species accumulation curves, 11 nonparametric, and one based in the species-area relationship) were compared by examining their performance in estimating the total species richness of epigean arthropods in the Azorean Laurisilva forests. Data obtained with standardized sampling of 78 transects in natural forest remnants of five islands were aggregated in seven different grains (i.e. ways of defining a single sample): islands, natural areas, transects, pairs of traps, traps, database records and individuals to assess the effect of using different sampling units on species richness estimations. 2. Estimated species richness scores depended both on the estimator considered and on the grain size used to aggregate data. However, several estimators (ACE, Chao1, Jackknife1 and 2 and Bootstrap) were precise in spite of grain variations. Weibull and several recent estimators [proposed by Rosenzweig et al. (Conservation Biology, 2003, 17, 864-874), and Ugland et al. (Journal of Animal Ecology, 2003, 72, 888-897)] performed poorly. 3. Estimations developed using the smaller grain sizes (pair of traps, traps, records and individuals) presented similar scores in a number of estimators (the above-mentioned plus ICE, Chao2, Michaelis-Menten, Negative Exponential and Clench). The estimations from those four sample sizes were also highly correlated. 4. Contrary to other studies, we conclude that most species richness estimators may be useful in biodiversity studies. Owing to their inherent formulas, several nonparametric and asymptotic estimators present insensitivity to differences in the way the samples are aggregated. Thus, they could be used to compare species richness scores obtained from different sampling strategies. Our results also point out that species richness estimations coming from small grain sizes can be directly compared and other estimators could give more precise results in those cases. We propose a decision framework based on our results and on the literature to assess which estimator should be used to compare species richness scores of different sites, depending on the grain size of the original data, and of the kind of data available (species occurrence or abundance data)

Catálogo de los briófitos epífitos que crecen en bosques de quercíneas del cuadrante noroccidental ibérico

[ES] En las últimas décadas se han producido importantes avances en el conocimiento de la brioflora ibérica. Gracias a ello se puede decir que hoy día la flora muscinal ibérica se conoce relativamente bien a nivel taxonómico. Sin embargo, en cuanto a las distribuciones de las especies aún queda mucho trabajo por hacer. La mayor parte de los estudios se han centrado en zonas montanas y/o singulares o bien en los entornos de las residencias de los especialistas. Esto ha producido un importante sesgo en el conocimiento de las distribuciones que es necesario solventar realizando estudios sistemáticos centrados en conseguir una muestra representativa de los principales gradientes ambientales y geográficos de la Península. Precisamente, el objetivo del presente trabajo es contribuir a reducir de forma significativa las lagunas en el conocimiento de la distribución de los briófitos epífitos ibéricos. Para ello, se ha estudiado buena parte de las mesetas centrales, incluyendo las porciones españolas de las cuencas del Duero y del Tajo, dos de las regiones menos exploradas de la Península Ibérica. El catálogo resultante incluye 89 especies de briófitos, entre las que hay 9 hepáticas y 80 musgos. El presente estudio aporta además 72 nuevas citas provinciales y amplía significativamente la distribución conocida de un buen número de especies. Queda patente la importancia de llevar a cabo muestreos sistemáticos representativos de los gradientes ambientales y geográficos en zonas poco exploradas de modo que se vayan rellenando los huecos en el conocimiento de las distribuciones de los briófitos ibéricos.[EN] Knowledge on the diversity and distributions of the Iberian bryophytes has experienced a remarkable progress in the last decades. As a consequence, the taxonomy of the Iberian bryophytes is relatively well known. However, regarding the distribution and abundance of species across the territory large knowledge gaps e xist. To date, most of the studies have been centered either in mountainous regions or in singular areas or accessible sites in the vicinity of specialist's residences. This has produced important sampling biases in the knowledge on the species distributions. Thus, to improve the quality of the data at hand, it is necessary to perform systematic surveys focused on attaining a representative sample of the main geographic and environmental gradients of the Iberian Peninsula. Within this broad objective the specific aim of this work is to contribute to significantly reduce the knowledge gaps on the distribution of Iberian epiphytic bryophytes. To do so, we have studied a large part of the Iberian plateaus including the Duero and Tajo basins within the Spanish territory, two of the least explored regions within the Iberian Peninsula. The obtained catalogue includes 89 bryophyte species including 9 liverworts and 80 mosses. Besides, we provide 72 provincial novelties that significantly enlarge the known distribution of a number of species. Altogether these results evidence that to fill in current knowledge gaps it is necessary to perform systematic survey campaigns aimed at representing the geographic and environmental variability of the territory.Este trabajo ha sido financiado por los proyectos concedidos por el Ministerio de Economía y Competitividad (CGL2013-43246-P) y el Ministerio de Ciencia e Innovación (CGL2011-28857/BOS) españoles. N.G. Medina realizó el trabajo con una beca del Ministerio de Educación (AP2007-00905).Peer Reviewe

Would species richness estimators change the observed species area relationship?

Copyright © 2008 Elsevier Masson SAS. All rights reserved.We evaluate whether the description of the species area relationship (SAR) can be improved by using richness estimates instead of observed richness values. To do this, we use three independent datasets gathered with standardized survey methods from the native laurisilva forest of the Azorean archipelago, encompassing different distributional extent and biological groups: soil epigean arthropods at eight forest fragments in Terceira Island, canopy arthropods inhabiting Juniperus brevifolia at 16 forest fragments of six different islands, and bryophytes of seven forest fragments from Terceira and Pico islands. Species richness values were estimated for each forest fragment using seven non-parametric estimators (ACE, ICE, Chao1, Chao2, Jackknife1, Jackknife2 and Bootstrap; five in the case of bryophytes). These estimates were fitted to classical log–log species–area curves and the intercept, slope and goodness of fit of these curves were compared with those obtained from the observed species richness values to determine if significant differences appear in these parameters. We hypothesized that the intercepts would be higher in the estimated data sets compared with the observed data, as estimated richness values are typically higher than observed values. We found partial support for the hypothesis – intercepts of the SAR obtained from estimated richness values were significantly higher in the case of epigean arthropods and bryophyte datasets. In contrast, the slope and goodness of fit obtained with estimated values were not significantly different from those obtained from observed species richness in all groups, although a few small differences appeared. We conclude that, although little is gained using these estimators if data come from standardized surveys, their estimations could be used to analyze macroecological relationships with non-standardized observed data, provided that survey incompleteness and/or unevenness are also taken into account

Environmental niche divergence among three dune shrub sister species with parapatric distributions

Background and Aims The geographical distributions of species are constrained by their ecological requirements. The aim of this work was to analyse the effects of environmental conditions, historical events and biogeographical constraints on the diversification of the three species of the western Mediterranean shrub genus Stauracanthus, which have a parapatric distribution in the Iberian Peninsula. Methods Ecological niche factor analysis and generalized linear models were used to measure the response of all Stauracanthus species to the environmental gradients and map their potential distributions in the Iberian Peninsula. The bioclimatic niche overlap between the three species was determined by using Schoener's index. The genetic differentiation of the Iberian and northern African populations of Stauracanthus species was characterized with GenalEx. The effects on genetic distances of the most important environmental drivers were assessed through Mantel tests and non-metric multidimensional scaling. Key Results The three Stauracanthus species show remarkably similar responses to climatic conditions. This supports the idea that all members of this recently diversified clade retain common adaptations to climate and consequently high levels of climatic niche overlap. This contrasts with the diverse edaphic requirements of Stauracanthus species. The populations of the S. genistoides-spectabilis clade grow on Miocene and Pliocene fine-textured sedimentary soils, whereas S. boivinii, the more genetically distant species, occurs on older and more coarse-textured sedimentary substrates. These patterns of diversification are largely consistent with a stochastic process of geographical range expansion and fragmentation coupled with niche evolution in the context of spatially complex environmental fluctuations. Conclusions: The combined analysis of the distribution, realized environmental niche and phylogeographical relationships of parapatric species proposed in this work allows integration of the biogeographical, ecological and evolutionary processes driving the evolution of species adaptations and how they determine their current geographical ranges.FCT [UID/Multi/04326/2013, SFRH/BD/65659/2009, SFRH/BPD/85040/2012]; Portuguese FCT project COMDUNES [EXPL/BIA-BIC/2311/2013]; FCT BI grant by project COMDUNES; Atraccion de Talento Investigador Programme (Gobierno de Extremadura) [TA13032]info:eu-repo/semantics/publishedVersio

The Macaronesian province: patterns of species richness and endemism of arthropods

"[…]. The Macaronesian arthropod fauna displays a number of characteristics typical of oceanic islands, including a high degree of endemism, ranging from 19% for the Azores (Borges et al., 2005a), to 28% for Madeira (Borges et al., 2008a), 30% for Cape Verde (Arechavaleta etal., 2005) and 45% for the Canary Islands (Izquierdo et al., 2004; see Table I). The preponderance of endemic species has made the Macaronesian islands an outstanding area for studies of evolution and speciation, and arthropods from these islands have been the focus of particularly intensive investigation in the last ten years. Numerous biogeographic analyses of Macaronesian arthropod groups have provided valuable insights into the processes regulating species richness as well as the relationships among the region's endemics (e.g. Juan et al.,1996; Arnedo & Ribera, 1999; Borges & Brown, 1999; Emerson et al., 1999, 2006; Emerson & Oromí, 2005; Dimitrov et al., 2008; Borges & Hortal, 2009; Hochkirch & Görzig, 2009). Here we investigate the factors shaping arthropod species richness and patterns of endemism in the Macaronesian archipelagos, considering two levels of analysis: a) individual archipelagos of the Macaronesian region (except Madeira and Salvages due to their limited number of islands), and b) all the islands of the region altogether. We do this following the recently published works of Whittaker et al. (2008) and Borges & Hortal (2009), examining data sets for several taxa from the Macaronesian archipelagos. […]." (da Introdução)Fundação para a Ciência e a Tecnologia, Portugal