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11.
Emilio Virgós Rafal Kowalczyk Atalya Trua Anna de Marinis Julián G. Mangas Jose M. Barea‐Azcón Eli Geffen 《Journal of Biogeography》2011,38(8):1546-1556
Aim To test the abundant centre hypothesis by analysing the physical and climatic factors that influence body size variation in the European badger (Meles meles). Location Data were compiled from 35 locations across Europe. Methods We used body mass, body length and condylo‐basal length (CBL) as surrogates of size. We also compiled data on latitude, several climatic variables, habitat type and site position relative to the range edge. We collapsed all continuous climatic variables into independent vectors using principal components analysis (PCA), and used a general linear model to explain the morphometric variation in badger populations across the species’ range. Results Body mass and body length were nonlinearly and significantly related to latitude. In contrast, CBL was linearly related to latitude. Body mass changed nonlinearly along the temperature (PC1) gradient, with the highest values observed at mid‐range. Furthermore, body mass, body length and CBL differed significantly among habitats, with badgers showing larger size in temperate habitats and core areas relative to peripheral zones. Main conclusions Our analysis supports the nonlinear pattern predicted by the abundant centre hypothesis only for body mass and body length. These results imply that individuals are largest and heaviest at the centre of the climatic range of badger distribution. Variation of CBL with latitude follows a linear trend, consistent with Bergmann’s rule. Our results provide mixed support for the abundant centre hypothesis, and suggest food availability/quality to be the main mechanism underlying body size clines in this species. 相似文献
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The largest survey on the perception of synthetic biology-related disciplines (Porcar et al., 2019,EMBO Rep 20) recently revealed that the Spanish society does not have a very positive perception of the term synthetic biology. On the other hand, the terms biotechnology and even genetic engineering received relatively higher scores. The issue of nomenclature and perception is a classical one in science perception studies. Synthetic biologists have been debating their neologism (Synthetic Biology, from now on SB) for years. Even in a 2006 blog, Rob Carlson discussed the various labels for the new field, such as intentional biology, constructive biology, natural engineering, synthetic genomics and biological engineering. This diversity of names, along with the above mentioned negative public perception of the term synthetic biology, raises the question on whether the term itself is suitable or whether it could, in an extreme scenario, be replaced by another combining scientific consensus with public acceptance. 相似文献
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Alexis M. Aranciaga Rolando Federico L. Agnolin Julián Corsolini 《Comptes Rendus Palevol》2019,18(7):725-734
The aim of the present contribution is to describe a new genus and species of Pipoidea from the Huitrera Formation (Eocene) from Patagonia, Argentina. The new genus shows a unique combination of characters indicating that it is a valid taxon different from other pipimorphs, including the coeval Llankibatrachus truebae. The phylogenetic analysis resulted in the nesting of the new taxon within a previously unrecognized endemic clade of South American aglossans. This new clade turns out to be the sister-group of crown-group Pipidae. This phylogenetic proposal reinforces the hypothesis sustaining the dispersal of pipids between Africa and South America through an island chain or a continental bridge across the Atlantic Ocean by Early Tertiary times. 相似文献
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Fire as a key driver of Earth's biodiversity 总被引:1,自引:0,他引:1
Tianhua He Byron B. Lamont Juli G. Pausas 《Biological reviews of the Cambridge Philosophical Society》2019,94(6):1983-2010
Many terrestrial ecosystems are fire prone, such that their composition and structure are largely due to their fire regime. Regions subject to regular fire have exceptionally high levels of species richness and endemism, and fire has been proposed as a major driver of their diversity, within the context of climate, resource availability and environmental heterogeneity. However, current fire‐management practices rarely take into account the ecological and evolutionary roles of fire in maintaining biodiversity. Here, we focus on the mechanisms that enable fire to act as a major ecological and evolutionary force that promotes and maintains biodiversity over numerous spatiotemporal scales. From an ecological perspective, the vegetation, topography and local weather conditions during a fire generate a landscape with spatial and temporal variation in fire‐related patches (pyrodiversity), and these produce the biotic and environmental heterogeneity that drives biodiversity across local and regional scales. There have been few empirical tests of the proposition that ‘pyrodiversity begets biodiversity’ but we show that biodiversity should peak at moderately high levels of pyrodiversity. Overall species richness is greatest immediately after fire and declines monotonically over time, with postfire successional pathways dictated by animal habitat preferences and varying lifespans among resident plants. Theory and data support the ‘intermediate disturbance hypothesis’ when mean patch species diversity is correlated with mean fire intervals. Postfire persistence, recruitment and immigration allow species with different life histories to coexist. From an evolutionary perspective, fire drives population turnover and diversification by promoting a wide range of adaptive responses to particular fire regimes. Among 39 comparisons, the number of species in 26 fire‐prone lineages is much higher than that in their non‐fire‐prone sister lineages. Fire and its byproducts may have direct mutagenic effects, producing novel genotypes that can lead to trait innovation and even speciation. A paradigm shift aimed at restoring biodiversity‐maintaining fire regimes across broad landscapes is required among the fire research and management communities. This will require ecologists and other professionals to spread the burgeoning fire‐science knowledge beyond scientific publications to the broader public, politicians and media. 相似文献
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Molecular taxonomic identification in the absence of a ‘barcoding gap’: a test with the endemic flora of the Canarian oceanic hotspot 下载免费PDF全文
Ruth Jaén‐Molina Águedo Marrero‐Rodríguez J. Alfredo Reyes‐Betancort Arnoldo Santos‐Guerra José Naranjo‐Suárez Juli Caujapé‐Castells 《Molecular ecology resources》2015,15(1):42-56
We use a comprehensive subset of Canarian angiosperms corresponding to 23 families, 35 genera and 60 Canarian endemic taxa to test whether this flora is suitable to taxonomic identification with the two proposed plant DNA barcode sequences and whether these sequences may reveal the existence of cryptic species overlooked by morphology. The rate of discrimination success between the insular congeneric samples using the rbcL+matK combination and a ‘character‐based’ approach (where we use only the combination of nucleotide positions in an alignment that allows unambiguous species identification) is higher (82.29%) than that obtained with the ‘distance‐based’ approach (80.20%) used by the CBOL Plant Working Group in 2009 and also when compared with tests conducted in other floras. This suggests that the molecular identification of the Canarian endemic flora can be achieved as successfully as in other floras where the incidence of radiation is not as relevant. The facts that (i) a distance‐based criterion was unable to discriminate between congeneric and conspecific comparisons and (ii) only the character‐based discrimination criterion resolved cases that the distance‐based criterion did not, further support the use of a character discrimination approach for a more efficient DNA barcoding of floras from oceanic islands like the Canaries. Thus, a barcoding gap seems not to be necessary for the correct molecular characterization of the Canarian flora. DNA barcodes also suggest the possible existence of cryptic taxa to be further investigated by morphology and that the current taxonomic status of some of the taxa analysed may need revision. 相似文献
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Carlos Eduardo Pinzón-Flórez Julián Alfredo Fernández-Ni?o Myriam Ruiz-Rodríguez álvaro J. Idrovo Abel Armando Arredondo López 《PloS one》2015,10(3)