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Anne Bauer focuses in her academic and journalistic work on the MEN A region, where she has spent most of her professional and academic life. Having worked as a researcher for a variety of German and international organizations, she specializes in issues of displacement, migration, conflict transformation, and mediation. Among others, her past work has addressed the Syrian war and its ramifications for neighboring countries, the Palestinian cause in the Arab world, and the multifaceted crises affecting Lebanon. Pascal Bernhard is a Swiss journalist and analyst for political affairs in the MEN A region. After having studied Philosophy and Islamic Studies in Zurich, he completed a journalist traineeship at the Zenith magazine, and wrote numerous pieces and interviews about international relations in the region, culture and religion. In his studies, he focuses on the Golf countries and the power-dynamics of conflicts such as Israel-Palestine, Yemen and Libya.

The following sections are included: Introduction Homology and Homoplasy: Look-alikes are Not Necessarily Closely Related Characters and Their States Homology — A Phylogenetic Hypothesis Ancestral or Derived — Qualifying the State of a Character Homoplasy — Pitfall in Phylogenetics Molecular Phylogenetics Gene Duplication vs. Speciation, Paralogy vs. Orthology Sequence Alignment — A Homology Hypothesis Evolutionary Time Evolutionary distance and the course of time Time and time again: paleontology and molecular evolution Micromutations and the molecular clock Tree Reconstitution The Tree Graph Model — Transmission of Phylogenetic Information Numerical Taxonomic Phenetics (NTP) The neighbor joining algorithm A common NTP artefact Cladistic Maximum Parsimony (CMP) Methods Symplesiomorphy, synapomorphy, and autapomorphy Cladistic maximum parsimony (CMP) and character compatibility (CC) methods CMP common artefacts Probabilistic Methods Searching for an Optimal Tree in a Large, Populated Space The number of possible phylogenetic trees The branch-and-bound algorithm Heuristic methods in tree reconstruction A rapid maximum likelihood method: RAxML Creating consensus trees Estimating tree robustness Recommended, Acceptable, and Unacceptable Groupings of Taxons Paraphylon — Acceptable with caveat Convergence and reversion polyphylons — Unacceptable Uses of Phylogenetics in Molecular Biology Prediction of Gene Function Advanced Phylogenetic Analyses and New Directions Phylogenetics Resources References

A bstract We compute all master integrals for massless three-loop four-particle scattering amplitudes required for processes like di-jet or di-photon production at the LHC. We present our result in terms of a Laurent expansion of the integrals in the dimensional regulator up to 8 th power, with coefficients expressed in terms of harmonic polylogarithms. As a basis of master integrals we choose integrals with integrands that only have logarithmic poles — called d log forms. This choice greatly facilitates the subsequent computation via the method of differential equations. We detail how this basis is obtained via an improved algorithm originally developed by one of the authors. We provide a public implementation of this algorithm. We explain how the algorithm is naturally applied in the context of unitarity. In addition, we classify our d log forms according to their soft and collinear properties.

Biodiversity–ecosystem functioning (BEF) experiments have shown that local species richness promotes ecosystem functioning and stability. Whether this also applies under real-world conditions is still debated. Here, we focus on larger scales of space, time and ecological organization. We develop a quasi-experimental design in which we relate land-cover type richness as measure of landscape richness to 17-year time series of satellite-sensed functioning in 4974 landscape plots 6.25 or 25 ha in size. We choose plots so that landscape richness is orthogonal to land cover-type composition and environmental conditions across climatic gradients. Landscape-scale productivity and temporal stability increase with landscape richness, irrespective of landscape plot size. Peak season near-infrared surface albedo, which is relevant for surface energy budgets, is higher in mixed than in single land-cover type landscapes. Effect sizes are as large as those reported from BEF-experiments, suggesting that landscape richness promotes landscape functioning at spatial scales relevant for management. Species richness is often reported to enhance ecosystem functioning, but it is unclear whether similar diversity-functioning relationships occur at larger scales. Here Oehri et al. combine land cover survey and remote sensing data to show a positive relationship between landscape diversity and landscape functioning.

Forest ecosystems are an integral component of the global carbon cycle as they take up and release large amounts of C over short time periods (C flux) or accumulate it over longer time periods (C stock). However, there remains uncertainty about whether and in which direction C fluxes and in particular C stocks may differ between forests of high versus low species richness. Based on a comprehensive dataset derived from field-based measurements, we tested the effect of species richness (3–20 tree species) and stand age (22–116 years) on six compartments of above- and below-ground C stocks and four components of C fluxes in subtropical forests in southeast China. Across forest stands, total C stock was 149 ± 12 Mg ha −1 with richness explaining 28.5% and age explaining 29.4% of variation in this measure. Species-rich stands had higher C stocks and fluxes than stands with low richness; and, in addition, old stands had higher C stocks than young ones. Overall, for each additional tree species, the total C stock increased by 6.4%. Our results provide comprehensive evidence for diversity-mediated above- and below-ground C sequestration in species-rich subtropical forests in southeast China. Therefore, afforestation policies in this region and elsewhere should consider a change from the current focus on monocultures to multi-species plantations to increase C fixation and thus slow increasing atmospheric CO 2 concentrations and global warming.

Data from experiments that manipulated grassland biodiversity across Europe and North America show that biodiversity increases an ecosystem’s resistance to, although not resilience after, climate extremes. Biodiversity loss threatens ecosystem reliability Tests to establish whether biodiversity buffers ecosystems against extreme climate events have produced strongly contrasting results. Forest Isbell et al . combine data from 46 experiments that manipulated grassland plant diversity and measured productivity across Europe and North America and find that yes, biodiversity does increase an ecosystem's resistance to climate extremes. Plots with just a few species had their productivity reduced by 50% during climate extremes, whereas this effect was halved with a greater number of species. However, biodiversity had no discernible effect on the ecosystem resilience, with both low and high biodiversity treatments recovering from climate extremes within a year. It remains unclear whether biodiversity buffers ecosystems against climate extremes, which are becoming increasingly frequent worldwide 1 . Early results suggested that the ecosystem productivity of diverse grassland plant communities was more resistant, changing less during drought, and more resilient, recovering more quickly after drought, than that of depauperate communities 2 . However, subsequent experimental tests produced mixed results 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 . Here we use data from 46 experiments that manipulated grassland plant diversity to test whether biodiversity provides resistance during and resilience after climate events. We show that biodiversity increased ecosystem resistance for a broad range of climate events, including wet or dry, moderate or extreme, and brief or prolonged events. Across all studies and climate events, the productivity of low-diversity communities with one or two species changed by approximately 50% during climate events, whereas that of high-diversity communities with 16–32 species was more resistant, changing by only approximately 25%. By a year after each climate event, ecosystem productivity had often fully recovered, or overshot, normal levels of productivity in both high- and low-diversity communities, leading to no detectable dependence of ecosystem resilience on biodiversity. Our results suggest that biodiversity mainly stabilizes ecosystem productivity, and productivity-dependent ecosystem services, by increasing resistance to climate events. Anthropogenic environmental changes that drive biodiversity loss thus seem likely to decrease ecosystem stability 14 , and restoration of biodiversity to increase it, mainly by changing the resistance of ecosystem productivity to climate events.