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Background: This study aims to reconstruct the evolutionary history of African shrews referred to the Crocidura olivieri complex. We tested the respective role of forest retraction/expansion during the Pleistocene, rivers (allopatric models), ecological gradients (parapatric model) and anthropogenic factors in explaining the distribution and diversification within this species complex. We sequenced three mitochondrial and four nuclear markers from 565 specimens encompassing the known distribution of the complex, i.e. from Morocco to Egypt and south to Mozambique. We used Bayesian phylogenetic inference, genetic structure analyses and divergence time estimates to assess the phylogenetic relationships and evolutionary history of these animals. Results: The C. olivieri complex (currently composed of C. olivieri, C. fulvastra, C. viaria and C. goliath) can be segregated into eight principal geographical clades, most exhibiting parapatric distributions. A decrease in genetic diversity was observed between central and western African clades and a marked signal of population expansion was detected for a broadly distributed clade occurring across central and eastern Africa and portions of Egypt (clade IV). The main cladogenesis events occurred within the complex between 1.37 and 0.48 Ma. Crocidura olivieri sensu stricto appears polyphyletic and C. viaria and C. fulvastra were not found to be monophyletic. Conclusions: Climatic oscillations over the Pleistocene probably played a major role in shaping the genetic diversity within this species complex. Different factors can explain their diversification, including Pleistocene forest refuges, riverine barriers and differentiation along environmental gradients. The earliest postulated members of the complex originated in central/eastern Africa and the first radiations took place in rain forests of the Congo Basin. A dramatic shift in the ecological requirements in early members of the complex, in association with changing environments, took place sometime after 1.13 Ma. Some lineages then colonized a substantial portion of the African continent, including a variety of savannah and forest habitats. The low genetic divergence of certain populations, some in isolated localities, can be explained by their synanthropic habits. This study underlines the need to revise the taxonomy of the C. olivieri complex.

During excavations of the early Roman temple of Shanhûr (near Luxor, Egypt) a large concentration of small fish bones was found in a younger occupation layer dated to the late 6th-early 7th century AD. The various taxa encountered in this Byzantine (Coptic) assemblage are described and quantified in terms of both number of fragments and minimum number of individuals. Fish lengths are reconstructed using power equations for those taxa for which sufficient modern reference material was available. After excluding natural taphonomic agents (otters, fish eating birds, natural death) it is argued that the deposit is anthropic and that the material represents the remains of fish sauce or of pickled fish. Other archaeozoological data from the literature, textual and archaeological evidence, as well as modern practices show that Nilotic fish were consumed in salted form from about 2500 years ago up to the present-day.

Zooarcheological evidence suggests that pigs were domesticated in Southwest Asia ∼8,500 BC. They then spread across the Middle and Near East and westward into Europe alongside early agriculturalists. European pigs were either domesticated independently or more likely appeared so as a result of admixture between introduced pigs and European wild boar. As a result, European wild boar mtDNA lineages replaced Near Eastern/Anatolian mtDNA signatures in Europe and subsequently replaced indigenous domestic pig lineages in Anatolia. The specific details of these processes, however, remain unknown. To address questions related to early pig domestication, dispersal, and turnover in the Near East, we analyzed ancient mitochondrial DNA and dental geometric morphometric variation in 393 ancient pig specimens representing 48 archeological sites (from the Pre-Pottery Neolithic to the Medieval period) from Armenia, Cyprus, Georgia, Iran, Syria, and Turkey. Our results reveal the first genetic signatures of early domestic pigs in the Near Eastern Neolithic core zone. We also demonstrate that these early pigs differed genetically from those in western Anatolia that were introduced to Europe during the Neolithic expansion. In addition, we present a significantly more refined chronology for the introduction of European domestic pigs into Asia Minor that took place during the Bronze Age, at least 900 years earlier than previously detected. By the 5th century AD, European signatures completely replaced the endemic lineages possibly coinciding with the widespread demographic and societal changes that occurred during the Anatolian Bronze and Iron Ages.

The Old World farming system arose in the semi-arid Mediterranean environments of southwest Asia. Pioneer farmers settling the interior of the Balkans by the early sixth millennium BC were among the first to introduce southwest Asian-style cultivation and herding into areas with increasingly continental temperate conditions. Previous research has shown that the bioarchaeological assemblages from early farming sites in southeast Europe vary in their proportions of plant and animal taxa, but the relationship between taxonomic variation and climate has remained poorly understood. To uncover associations between multiple species and environmental factors simultaneously, we explored a dataset including altitude, five bioclimatic and 30 bioarchaeological variables (plant and animal taxa) for 57 of the earliest farming sites in southeast Europe using Canonical Correspondence Analysis (CCA). An extension of correspondence analysis, CCA is widely used in applied ecology to answer similar questions of species-environment relationships, but has not been previously applied in prehistoric archaeology to explore taxonomic and climatic variables in conjunction. The analyses reveal that the changes in plant and animal exploitation which occurred with the northward dispersal of farmers, crops and livestock correlate with south-north climate gradients, and emphasize the importance of adaptations in the animal domain for the initial establishment of farming beyond the Mediterranean areas.

How modern humans dispersed into Eurasia and Australasia, including the number of separate expansions and their timings, is highly debated [ 1, 2 ]. Two categories of models are proposed for the dispersal of non-Africans: (1) single dispersal, i.e., a single major diffusion of modern humans across Eurasia and Australasia [ 3–5 ]; and (2) multiple dispersal, i.e., additional earlier population expansions that may have contributed to the genetic diversity of some present-day humans outside of Africa [ 6–9 ]. Many variants of these models focus largely on Asia and Australasia, neglecting human dispersal into Europe, thus explaining only a subset of the entire colonization process outside of Africa [ 3–5, 8, 9 ]. The genetic diversity of the first modern humans who spread into Europe during the Late Pleistocene and the impact of subsequent climatic events on their demography are largely unknown. Here we analyze 55 complete human mitochondrial genomes (mtDNAs) of hunter-gatherers spanning ∼35,000 years of European prehistory. We unexpectedly find mtDNA lineage M in individuals prior to the Last Glacial Maximum (LGM). This lineage is absent in contemporary Europeans, although it is found at high frequency in modern Asians, Australasians, and Native Americans. Dating the most recent common ancestor of each of the modern non-African mtDNA clades reveals their single, late, and rapid dispersal less than 55,000 years ago. Demographic modeling not only indicates an LGM genetic bottleneck, but also provides surprising evidence of a major population turnover in Europe around 14,500 years ago during the Late Glacial, a period of climatic instability at the end of the Pleistocene.

Context The climate on Earth is changing due to the increased emissions of CO2 into the atmosphere, and these changes are expected to have a predominantly negative impact, with potentially dramatic economic, social and environmental consequences. The increased concentrations of CO2 are already resulting in acidification of the oceans, which adds further to the environmental pressure. Reducing the emissions of CO2 is therefore of prime importance. CO2 Capture and Storage (CCS) is considered as an essential element in the portfolio of measures, and has the potential to reduce the CO2 emissions from large industrial facilities to nearly zero. This has been recognised by the international community and especially Europe is being proactive in stimulating the development and implementation of CCS. Policy related research on CCS in Belgium has been centralised in the PSS-CCS projects (Policy Support System for Carbon Capture and Storage). Phase one (PSS-CCS I) started at the end of 2005 and the results were integrally published in 2009 (Piessens et al., 2009). This work was continued in the projects PSS-CCS II, the actual phase two, and the international valorisation project PSS-CCS BeNe which extended the scope to the Netherlands and created official bridges between the national CCS projects in Belgium and the Netherlands (CATO-2). Objectives From the start, the PSS-CCS projects (Policy Support System for Carbon Capture and Storage) have promised to provide detailed and objective insights in the role that CCS can play in the CO2 mitigation efforts of Belgium. Achieving this central objective is only possible by bringing together information, data and methodologies from widely different fields. The list below gives a brief overview of these activities, which have often resulted in deliverables which are usually to be regarded as important achievements in their own right. - Inventory of the industrial emission sources for CO2 in Belgium at plant and sector level, for providing an actual view on these emissions and the need to replace aging infrastructure. - Economic and technical analysis of the different technologies and their performance that allow capturing CO2 from power plants and other industrial facilities. - Development and calibration of a least-cost routing application for transport of CO2 by pipeline. - Summary of the geological data to identify geological reservoirs (aquifers and coal related storage options) that are potentially suited for geological storage of CO2. - Risk evaluation of different types of reservoirs and a techno-economic overview of the different techniques to monitor a CO2 reservoir. - Overview of the storage options in neighbouring countries accessible from Belgium, and an assessment on the domestic use of these reservoirs in those countries. - Analysis of the production, conversion and consumption of energy in Belgium using the TIMES-BE model, including CCS technologies. - Development of the PSS II simulator for detailed and ad-hoc predictions of CCS implementation in Belgium. - Evaluating the simulation results of the two models regarding the economic and environmental role that CCS can play under different scenarios. Conclusions The PSS-CCS projects have looked into the different, but related aspects of CCS. Capture of CO2 in the power sector is retaken and update in this report, but particular attention is given to how capture technologies can be integrated in industrial production processes. Particular attention is given to the production of cement, iron and steel, hydrogen, ammonia, refineries and industrial boilers, making this report a reference document for the capture from industrial sources. Cost estimates of those technologies are provided where possible, often indicating that capture can be more cost efficiently than in the power sector (e.g. steel, hydrogen...). For others, such as refineries, it may be quite challenging because of the complexity of such installations. The storage of CO2 is only of secondary importance when considering only costs, but is essential in the project planning and communication. This is why, now demonstration projects in neighbouring countries have become a reality, this topic is attracting an increasing amount of attention. This report in particularly looks at storage in coal bearing sequences by evaluating the different potential migration routes of CO2. In an attempt to quantify the amounts of CO2 that may migrate to the surface, a comparison is made with published estimates. Conservative estimates for leakage along abandoned wells would be below the health concentration of CO2, and vertical migration of CO2 in the Campine Basin in absence of such wells or conductive faults would be below meter scale at a 100y time resolution. Migration of CO2 out of the coal-bearing strata would be even more difficult, since coal acts as both a reservoir and seal, and additional sealing layers are present within the heterogeneous sequence. Nevertheless, as also required by European law, extensive monitoring is required. A portfolio of different technologies is required to achieve a the resolution required for confirming that CO2 is not leaking from the reservoir, leading to relatively high monitoring costs for small reservoirs or reservoirs with low injectivity. A comprehensive overview of the coal sequences in the Hainaut Basin indicates a storage potential of 500 to 700 Mt in this area. Injection strategies for coal are discussed acknowledging the geological particularities of this coal basin. The capacity of the Dinantian aquifer in this area is comparable to that of coal, but of particularly interest because of the high injectivity. The databases of the PSS simulator have been updated and extended according to the newly acquired data in this project, and have been calibrated for pipeline routing against confidential data from industry. Together with the important improvements, the current version (PSS II) produces realistic and reliable forecasts on power technologies based on coal, natural gas and biomass, as well as for the steel sector. PSS II is used in parallel with TIMES-BE, using large the same databases to make the results compatible. These models show that CCS will be a likely economic option in the power sector, but especially in industry. However, relatively high ETS prices for CO2 emissions are required to trigger large scale implementation of CCS in especially the power sector. An essential factor in assuring that very low emission targets are realised by 2050, a portfolio of technologies is required: if technologies are left out, the probability that the low targets are reached decreases dramatically. Technology lock-in additionally poses a real threat, but can be mitigated with appropriate policy measures. When it comes to storage, the development of domestic storage capacity is justified, although Belgium will additionally have to rely on the export of CO2. Contribution of the project in a context of scientific support to a sustainable development policy During the more or less five years during which the PSS-CCS projects have been active, they have been able to fill the need for information and follow-up on the topic of CCS in Belgium. This resulted in a large and active follow-up committee representing over 30 institutes, including many administrations and stakeholders that weigh on environmental and economic policy. The different valorisation events of the project were initially strongly focussed on the dissemination of correct and objective information on CCS, for which the international interest was strongly growing. This was in line with the activities within the project of which the earliest tasks were focussed on gathering and organising the data required for modelling the role of CCS. Energy models in Belgium were at that time also looking to include data on CCS technologies as a future option, leading to a direct feed of information into e.g. the Belgian TIMES- BE model. Also the reports of the Federal Planning Bureau (PRIMES model) cite PSS-CCS as a main reference. An important surge for information was during the preparation of the European CCS directive (Directive 2009/31/EC). Technical information regarded mainly the storage of CO2, the prime focus of the directive, but also the outlooks produced by the project were used to consider the scale and relevance of CCS for Belgium. Also other organisations and networks called upon the PSS-CCS partners for direct advice, or for presentations on the topic. The reader is referred to chapter 4 (DISSEMINATION AND VALORISATION) for an overview of the main and official valorisation activities originating from the PSS-CCS projects. Within Belgium and its regions, CCS is a well-known and documented option in mid- and long-term energy projections thanks to the catalytic role of the PSS-CCS projects. The now fully mature PSS II simulator and its databases currently play an important role in exchange activities with other countries through European collaboration and network projects (e.g. Welkenhuysen & Piessens, 2011b). This export of expertise may result in an impact in those countries, comparable to that of the PSS-CCS projects in Belgium.