Cross-realm assessment of climate change impacts on species' abundance trends

Climate change, land-use change, pollution and exploitation are among the main drivers of species' population trends; however, their relative importance is much debated. We used a unique collection of over 1,000 local population time series in 22 communities across terrestrial, freshwater and marine realms within central Europe to compare the impacts of long-term temperature change and other environmental drivers from 1980 onwards. To disentangle different drivers, we related species' population trends to species- and driver-specific attributes, such as temperature and habitat preference or pollution tolerance. We found a consistent impact of temperature change on the local abundances of terrestrial species. Populations of warm-dwelling species increased more than those of cold-dwelling species. In contrast, impacts of temperature change on aquatic species' abundances were variable. Effects of temperature preference were more consistent in terrestrial communities than effects of habitat preference, suggesting that the impacts of temperature change have become widespread for recent changes in abundance within many terrestrial communities of central Europe.Additionally, we appreciate the open access marine data provided by the International Council for the Exploration of the Sea. We thank the following scientists for taxonomic or technical advice: C. Brendel, T. Caprano, R. Claus, K. Desender, A. Flakus, P. R. Flakus, S. Fritz, E.-M. Gerstner, J.-P. Maelfait, E.-L. Neuschulz, S. Pauls, C. Printzen, I. Schmitt and H. Turin, and I. Bartomeus for comments on a previous version of the manuscript. R.A. was supported by the EUproject LIMNOTIP funded under the seventh European Commission Framework Programme (FP7) ERA-Net Scheme (Biodiversa, 01LC1207A) and the long-term ecological research program at the Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB). R.W.B. was supported by the Scottish Government Rural and Environment Science and Analytical Services Division (RESAS) through Theme 3 of their Strategic Research Programme. S.D. acknowledges support of the German Research Foundation DFG (grant DO 1880/1-1). S.S. acknowledges the support from the FP7 project EU BON (grant no. 308454). S.K., I.Kü. and O.S. acknowledge funding thorough the Helmholtz Association’s Programme Oriented Funding, Topic ‘Land use, biodiversity, and ecosystem services: Sustaining human livelihoods’. O.S. also acknowledges the support from FP7 via the Integrated Project STEP (grant no. 244090). D.E.B. was funded by a Landes–Offensive zur Entwicklung Wissenschaftlich–ökonomischer Exzellenz (LOEWE) excellence initiative of the Hessian Ministry for Science and the Arts and the German Research Foundation (DFG: Grant no. BO 1221/23-1).Peer Reviewe

Parallel habitat specialization within the wolf spider genus Hogna from the Galapagos

Within most island archipelagos, such as the Galapagos, similar ecological gradients are found on geographically isolated islands. Species radiations in response to these ecological gradients may follow different scenarios being (i) a single habitat specialization event followed by secondary colonization of each ecotype on the different islands or (ii) repeated and parallel habitat specialization on each island separately. This latter scenario has been considered less likely as gene flow might hamper such ecotypic differentiation. At least for the Galapagos, the extent to which this process is involved in species radiations remains yet poorly understood. Within the wolf spider genus Hogna, seven species are described that can be divided into three different ecotypes based on general morphology and habitat preference i.e. species that inhabit the pampa vegetation in the highlands, species that occur in coastal dry habitats and one generalist species. Comparison of the species phylogeny based on one mitochondrial (COI) and one nuclear (28S) gene fragment convincingly demonstrates that 'pampa' and 'coastal dry' species evolved in parallel on the islands Santa Cruz and San Cristobal. Despite the observation that allozymes analysis indicated that each species forms a distinct genetic cluster, phylogenetic divergence within these species complexes was very low and paraphyletic and most likely due to hybridization rather than incomplete lineage sorting, as demonstrated for the Santa Cruz species complex. This suggests that within-island speciation occurred under low levels of gene flow. Species phylogeny in general did not follow the progression of island emergence as a molecular clock analysis suggested that island endemic species may have diverged after as well as before the emergence of the islands. This represents the first clear example of parallel and within-island speciation because of habitat specialization on the Galapagos and that such divergence most likely occurred under historic gene flow

Citocinas en la patogenia de la enfermedad inflamatoria intestinal

Producción CientíficaDietary gluten induces an early response in the intestine of coeliac disease patients (CD), within a few hours, and this is driven by high levels of proinflammatory cytokines, including IFNg and IL-15, as has been thoroughly shown by gluten stimulation of biopsy explants. Our aim was to identify the immune mediators involved in the long-standing inflammation in untreated CD patients at diagnosis. mRNA and protein levels of TNFa, IL-12(p35), IL-12(p40), IL-15, IL-18 and IL-23(p19) were quantified in biopsies from active CD patients, CD patients on a gluten-free diet (GFD), healthy controls, and patients with non-CD inflammation and mild histological changes in the intestine. Biopsies from CD patients on a GFD were also stimulated in vitro with gliadin, and protein expression of IL-15 and IL-18 was analysed. Levels of IL-12 and IL-23 mRNA are nearly absent, and TNFa levels remain unchanged among different groups. Both the active and inactive forms of IL-18 protein have been found in all samples from active CD, and protein expression was only localized within the crypts. Levels of IL-15 mRNA remain unchanged, and protein expression, localized within the lamina propria, is found in a small number of samples. In vitro stimulation with gluten induces the expression of IL-15 and IL-18. In active CD, the early response following gluten intake characterized by high IFNg levels is driven by IL-18, and probably IL-15, and this alternates with periods of long-standing inflammation with moderate IFNg levels, maintained by IL-18 alone