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Sphagnum magellanicum Brid. is a worldwide distributed peat moss and an ecosystem-engineer in temperate and boreal bog ecosystems suggesting a great adaptive potential to different environmental conditions. Phenotypes of S. magellanicum have been described as one species so far, although this has been questioned by the detection of several genetic groups in a recent global study. Concordant with morphological uniformity, our analyses of Mid-to Northern European plants revealed only minimal variation in nuclear nrITS and plastid rps4 sequences. However, we detected two distinct genetic groups within Europe by analyzing microsatellite data of 298 individuals from 27 populations. Plants formed an Eastern and a Western European cluster, with overlapping areas in northern Germany and southern Sweden where plants of both clusters coexist within populations but show no signs of admixture. These two cryptic taxa seem therefore to be reproductively isolated. Bayesian analyses indicated that reproductive isolation occurred before the end of the late Pleistocene glaciations. After the meltdown of the glaciers, both clusters colonized northern and central Europe from glacial refugia in the West and possibly from Euro-Siberian populations. To test for divergent adaptation to environmental conditions, we exposed plants of both clusters to experimental climate warming treatments at two different plant-diversity levels (monocultures vs. mixtures) for two years. Despite their different evolutionary history, plants of both genetic clusters responded equally to climate treatments in our southern common garden near Potsdam, Germany. However, only eastern cluster populations benefited from plant-community diversity and increased their biomass in mixtures. These differences in their ecological niche match the diverging microhabitat preferences observed in situ and may effectively hamper genetic exchange if distances between microhabitats are too large for Sphagnum sperm movement. (C) 2017 Elsevier GmbH. All rights reserved.
Reciprocal selection between aphids, their protective endosymbionts, and the parasitoid wasps that prey upon them offers an opportunity to study the basis of their coevolution. We investigated adaptation to symbiont‐conferred defense by rearing the parasitoid wasp Lysiphlebus fabarum on aphids (Aphis fabae) possessing different defensive symbiont strains (Hamiltonella defensa). After ten generations of experimental evolution, wasps showed increased abilities to parasitize aphids possessing the H. defensa strain they evolved with, but not aphids possessing the other strain. We show that the two symbiont strains encode different toxins, potentially creating different targets for counter‐adaptation. Phenotypic and behavioral comparisons suggest that neither life‐history traits nor oviposition behavior differed among evolved parasitoid lineages. In contrast, comparative transcriptomics of adult female wasps identified a suite of differentially expressed genes among lineages, even when reared in a common, symbiont‐free, aphid host. In concurrence with the specificity of each parasitoid lineages’ infectivity, most differentially expressed parasitoid transcripts were also lineage‐specific. These transcripts are enriched with putative venom toxins and contain highly expressed, potentially defensive viral particles. Together, these results suggest that wild populations of L. fabarum employ a complicated offensive arsenal with sufficient genetic variation for wasps to adapt rapidly and specifically to their hosts’ microbial defenses.
Epigenetic mechanisms convey environmental information through generations and can regulate gene expression. Epigenetic studies in wild mammals are rare, but enable understanding adaptation processes as they may occur in nature. In most wild mammal species, males are the dispersing sex and thus often have to cope with differing habitats and thermal changes more rapidly than the often philopatric females. As temperature is a major environmental selection factor, we investigated whether genetically heterogeneous Wild guinea pig (Cavia aperea) males adapt epigenetically to an increase in temperature, whether that response will be transmitted to the next generation(s), and whether it regulates mRNA expression. Five (F0) adult male guinea pigs were exposed to an increased ambient temperature for 2 months, corresponding to the duration of the species' spermatogenesis. To study the effect of heat, we focused on the main thermoregulatory organ, the liver. We analyzed CpG-methylation changes of male offspring (F1) sired before and after the fathers' heat treatment (as has recently been described in Weyrich et al. [Mol. Ecol., 2015]). Transcription analysis was performed for the three genes with the highest number of differentially methylated changes detected: the thermoregulation gene Signal Transducer and Activator of Transcription 3 (Stat3), the proteolytic peptidase gene Cathepsin Z (Ctsz), and Sirtuin 6 (Sirt6) with function in epigenetic regulation. Stat3 gene expression was significantly reduced (P < 0.05), which indicated a close link between CpG-methylation and expression levels for this gene. The two other genes did not show gene expression changes. Our results indicate the presence of a paternal transgenerational epigenetic effect. Quick adaptation to climatic changes may become increasingly relevant for the survival of wildlife species as global temperatures are rising.
The literature on the costing of mitigation measures for reducing impacts of natural hazards is rather fragmented. This paper provides a concise overview of the current state of knowledge in Europe on the costing of mitigation measures for the reduction of natural hazard risks (droughts, floods, storms and induced coastal hazards as well as alpine hazards) and identifies knowledge gaps and related research recommendations. Furthermore, it provides a taxonomy of related mitigation options, classifying them into nine categories: (1) management plans, land-use planning, and climate adaptation; (2) hazard modification; (3) infrastructure; (4) mitigation measures (stricto sensu); (5) communication in advance of events; (6) monitoring and early warning systems; (7) emergency response and evacuation; (8) financial incentives; and (9) risk transfer (including insurance). It is found that the costing of mitigation measures in European and in other countries has almost exclusively focused on estimating direct costs. A cost assessment framework that addresses a range of costs, possibly informed by multiple stakeholders, would provide more accurate estimates and could provide better guidance to decision makers. (C) 2014 American Society of Civil Engineers.
The coastal stretch of north-eastern Mediterranean Morocco holds vitally important ecological, social, and economic functions. The implementation of large-scale luxury tourism resorts shall push socio-economic development and facilitate the shift from a mainly agrarian to a service economy. Sufficient water availability and intact beaches are among the key requirements for the successful realization of regional development plans. The water situation is already critical, additional water-intense sectors could overstrain the capacity of water resources. Further, coastal erosion caused by sea-level rise is projected. Regional climate change is observable, and must be included in regional water management. Long-term climate trends are assessed for the larger region (Moulouya basin) and for the near-coastal zone at Saidia. The amount of additional water demand is assessed for the large-dimensioned Saidia resort; including the monthly, seasonal and annual tourist per capita water need under inclusion of irrigated golf courses and garden areas. A shift of climate patterns is observed, a lengthening of the dry summer season, and as well a significant decline of annual precipitation. Thus, current water scarcity is mainly human-induced; however, climate change will aggravate the situation. As a consequence, severe environmental damage due to water scarcity is likely and could impinge on the quality of local tourism. The re-adjustment of current management routines is therefore essential. Possible adjustments are discussed and the analysis concludes with management recommendations for innovative regional water management of tourism facilities.