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Biotic interactions are known to affect the composition of species assemblages via several mechanisms, such as competition and facilitation. However, most spatial models of species richness do not explicitly consider inter‐specific interactions. Here, we test whether incorporating biotic interactions into high‐resolution models alters predictions of species richness as hypothesised. We included key biotic variables (cover of three dominant arctic‐alpine plant species) into two methodologically divergent species richness modelling frameworks – stacked species distribution models (SSDM) and macroecological models (MEM) – for three ecologically and evolutionary distinct taxonomic groups (vascular plants, bryophytes and lichens). Predictions from models including biotic interactions were compared to the predictions of models based on climatic and abiotic data only. Including plant–plant interactions consistently and significantly lowered bias in species richness predictions and increased predictive power for independent evaluation data when compared to the conventional climatic and abiotic data based models. Improvements in predictions were constant irrespective of the modelling framework or taxonomic group used. The global biodiversity crisis necessitates accurate predictions of how changes in biotic and abiotic conditions will potentially affect species richness patterns. Here, we demonstrate that models of the spatial distribution of species richness can be improved by incorporating biotic interactions, and thus that these key predictor factors must be accounted for in biodiversity forecasts. 相似文献
83.
Peter Sarkies Murray E. Selkirk John T. Jones Vivian Blok Thomas Boothby Bob Goldstein Ben Hanelt Alex Ardila-Garcia Naomi M. Fast Phillip M. Schiffer Christopher Kraus Mark J. Taylor Georgios Koutsovoulos Mark L. Blaxter Eric A. Miska 《PLoS biology》2015,13(2)
Small RNA pathways act at the front line of defence against transposable elements across the Eukaryota. In animals, Piwi interacting small RNAs (piRNAs) are a crucial arm of this defence. However, the evolutionary relationships among piRNAs and other small RNA pathways targeting transposable elements are poorly resolved. To address this question we sequenced small RNAs from multiple, diverse nematode species, producing the first phylum-wide analysis of how small RNA pathways evolve. Surprisingly, despite their prominence in Caenorhabditis elegans and closely related nematodes, piRNAs are absent in all other nematode lineages. We found that there are at least two evolutionarily distinct mechanisms that compensate for the absence of piRNAs, both involving RNA-dependent RNA polymerases (RdRPs). Whilst one pathway is unique to nematodes, the second involves Dicer-dependent RNA-directed DNA methylation, hitherto unknown in animals, and bears striking similarity to transposon-control mechanisms in fungi and plants. Our results highlight the rapid, context-dependent evolution of small RNA pathways and suggest piRNAs in animals may have replaced an ancient eukaryotic RNA-dependent RNA polymerase pathway to control transposable elements. 相似文献
84.
HDAC4 deacetylase associates with and represses the MEF2 transcription factor. 总被引:28,自引:0,他引:28
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E A Miska C Karlsson E Langley S J Nielsen J Pines T Kouzarides 《The EMBO journal》1999,18(18):5099-5107
85.
The regional species richness and genetic diversity of Arctic vegetation reflect both past glaciations and current climate
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Lærke Stewart Inger G. Alsos Christian Bay Amy L. Breen Christian Brochmann Noémie Boulanger‐Lapointe Olivier Broennimann Helga Bültmann Peder Klith Bøcher Christian Damgaard Fred J. A. Daniëls Dorothee Ehrich Pernille Bronken Eidesen Antoine Guisan Ingibjörg Svala Jónsdóttir Jonathan Lenoir Peter C. le Roux Esther Lévesque Miska Luoto Jacob Nabe‐Nielsen Peter Schönswetter Andreas Tribsch Liv Unn Tveraabak Risto Virtanen Donald A. Walker Kristine B. Westergaard Nigel G. Yoccoz Loïc Pellissier 《Global Ecology and Biogeography》2016,25(4):430-442
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Anna Astorga Jari Oksanen Miska Luoto Janne Soininen Risto Virtanen Timo Muotka 《Global Ecology and Biogeography》2012,21(3):365-375
Aim An intensively debated issue in macroecology is whether unicellular organisms show biogeographic patterns different from those of macroorganisms. One aspect of this debate addresses beta diversity, that is, do microbial organisms exhibit distance‐decay patterns similar to those of macroorganisms? And if so, is the decay of community similarity caused by spatially limited dispersal or by niche‐related factors? We studied the community similarity of stream diatoms, macroinvertebrates and bryophytes across the same set of sites in relation to environmental and geographic distance. Location A geographical gradient of c. 1100 km in Finland. Methods We first identified the subset of environmental variables that produced the highest correlation with community similarities for each taxonomic group. Based on these variables, we used partial Mantel tests to separate the independent influences of environmental and geographical distance for distance decay of community similarity, separately for diatoms, bryophytes and macroinvertebrates. Finally, macroinvertebrates were divided into three groups based on their different dispersal categories and a partial Mantel test was used to assess whether each of these groups were differently affected by environmental versus geographic distance, i.e. is dispersal a key factor in tests of niche versus neutral models. Results The level of environmental control was by far the strongest for diatoms; however, all groups were controlled more by environmental factors than by limited dispersal. Macroinvertebrate species with low dispersal ability were significantly related to geographic distance, while more effective dispersers showed no relationship to geography but were instead strongly related to environmental distance. Main conclusions Our results suggest that patterns between macro‐ and microorganisms are not fundamentally different, but the level of environmental control varies according to dispersal ability. The relative importance of niche versus dispersal processes is not simply a function of organism size but other traits (e.g. life‐history type, dispersal capacity) may obscure this relationship. 相似文献
89.
Current predictions of how species will respond to climate change are typically based on coarse-grained climate surfaces utilizing
bioclimate envelope modelling. However, the suitability of environmental conditions for a given species might result from
a variety of factors including some unrelated to climate. To address this issue, we investigated whether the inclusion of
topographical and soil information in bioclimatic envelope models would significantly alter predictions of climate change—induced
fine-scale tree and shrub species range size changes at the tree-limit in subarctic Europe. Using generalized additive models
and data on current climate and species distributions and three different climate scenarios for the period 2040–2069, we developed
predictions of the currently suitable area and potential range size changes of seven tree and shrub species in an area of
1,100 km2 at a resolution of 1-ha. The inclusion of topography and soil information increased the predictive accuracy of climate-only
models for all studied species. The predicted changes in species distribution volumes were contradictory, and the predicted
occurrences varied greatly depending on the model used. Our results therefore support the arguments that vegetation responses
to climate change can be influenced by local environmental conditions and that attention should be paid to the combined effects
of these factors. We conclude that disregarding local topography and soil conditions in bioclimatic models may result in biased
projections of range expansions and the associated colonization, extinction and turnover assessments. 相似文献
90.
Patrick Royston Friederike M-S Barthel Mahesh KB Parmar Babak Choodari-Oskooei Valerie Isham 《Trials》2011,12(1):1-18