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Tree-ring chronologies underpin the majority of annually-resolved reconstructions of Common Era climate. However, they are derived using different datasets and techniques, the ramifications of which have hitherto been little explored. Here, we report the results of a double-blind experiment that yielded 15 Northern Hemisphere summer temperature reconstructions from a common network of regional tree-ring width datasets. Taken together as an ensemble, the Common Era reconstruction mean correlates with instrumental temperatures from 1794-2016 CE at 0.79 (p < 0.001), reveals summer cooling in the years following large volcanic eruptions, and exhibits strong warming since the 1980s. Differing in their mean, variance, amplitude, sensitivity, and persistence, the ensemble members demonstrate the influence of subjectivity in the reconstruction process. We therefore recommend the routine use of ensemble reconstruction approaches to provide a more consensual picture of past climate variability.

Based on existing knowledge and current research projects, a number of innovative strategies and approaches are proposed that would enable organic animal farming to contribute to a more sustainable and resilient food systems that also impacts positively on our surrounding socio-ecological landscape. The focus is on 1) integrated, multispecies, diversified systems, 2) sustainable foraging strategies and efficient utilisation of natural resources, 3) home grown protein feed especially for monogastric animals, 4) resilience as the core of health development rather than just freedom of diseases, 5) breeding including multipurpose breeds, and 6) enhanced mother-infant contact.

At the local scale, artificial impounded reservoirs in dry regions exert influence on the surrounding local climate. Impounded reservoirs have been found to alter precipitation patterns and increase temperature, specific humidity and surface evaporation. The consequences of impoundment or its related climatic changes on the surrounding vegetation are still not well understood. We here examined the potential effect on surrounding tree growth of the impoundment of the Ertan Reservoir, China, in 1998. We measured Yunnan pine tree rings at three sites on a slope close to the reservoir and two control sites far away from the reservoir. We compared the annual radial growth of tree rings at all sites with air temperature, precipitation and air humidity in the region. We also used cumulative distribution functions to quantify the probability of attributing radial growth changes to background climate variability. We find an enhancement of tree growth from 2000 to 2002, right after the reservoir's impounding in experimental and control sites. Hence, the tree growth can initially be explained by favourable conditions benefiting tree growth. However, we cannot entirely attribute such enhancement to the background climate variability when studying the relationship between tree growth and climatic variables over the 36 years and their probability of occurrence. Tree growth in the three years following impoundment can only be attributed to the simultaneous effect of favourable regional climate conditions and the reservoir's impoundment in itself. These conditions decrease vegetation stress by decreasing air temperature and increasing air relative humidity. Although the findings of this study shed more light on the environmental and climatic changes induced by the impoundment of reservoirs, they also call for the need of monitoring climatic variables in the vicinity of reservoirs.

Tree-ring chronologies underpin the majority of annually-resolved reconstructions of Common Era climate. However, they are derived using different datasets and techniques, the ramifications of which have hitherto been little explored. Here, we report the results of a double-blind experiment that yielded 15 Northern Hemisphere summer temperature reconstructions from a common network of regional tree-ring width datasets. Taken together as an ensemble, the Common Era reconstruction mean correlates with instrumental temperatures from 1794-2016 CE at 0.79 (p<0.001), reveals summer cooling in the years following large volcanic eruptions, and exhibits strong warming since the 1980s. Differing in their mean, variance, amplitude, sensitivity, and persistence, the ensemble members demonstrate the influence of subjectivity in the reconstruction process. We therefore recommend the routine use of ensemble reconstruction approaches to provide a more consensual picture of past climate variability. Tree rings are a crucial archive for Common Era climate reconstructions, but the degree to which methodological decisions influence outcomes is not well known. Here, the authors show how different approaches taken by 15 different groups influence the ensemble temperature reconstruction from the same data.

The feeding behavior of the giant ambush-predator Bobbit worm (Eunice aphroditois) is spectacular. They hide in their burrows until they explode upwards grabbing unsuspecting prey with a snap of their powerful jaws. The still living prey are then pulled into the sediment for consumption. Although predatory polychaetes have existed since the early Paleozoic, their bodies comprise mainly soft tissue, resulting in a very incomplete fossil record, and virtually nothing is known about their burrows and behavior beneath the seafloor. Here we use morphological, sedimentological, and geochemical data from Miocene strata in northeast Taiwan to erect a new ichnogenus, Pennichnus. This trace fossil consists of an up to 2 m long, 2-3 cm in diameter, L-shaped burrow with distinct feather-like structures around the upper shaft. A comparison of Pennichnus to biological analogs strongly suggests that this new ichnogenus is associated with ambush-predatory worms that lived about 20 million years ago.

Soluble urokinase-type plasminogen activator receptor (suPAR) is a chronic inflammation marker associated with the development of a range of diseases, including cancer and cardiovascular disease. The genetics of suPAR remain unexplored but may shed light on the biology of the marker and its connection to outcomes. We report a heritability estimate of 60% for the variation in suPAR and performed a genome-wide association meta-analysis on suPAR levels measured in Iceland (N = 35,559) and in Denmark (N = 12,177). We identified 13 independently genome-wide significant sequence variants associated with suPAR across 11 distinct loci. Associated variants were found in and around genes encoding uPAR (PLAUR), its ligand uPA (PLAU), the kidney-disease-associated gene PLA2R1 as well as genes with relations to glycosylation, glycoprotein biosynthesis, and the immune response. These findings provide new insight into the causes of variation in suPAR plasma levels, which may clarify suPAR's potential role in associated diseases, as well as the underlying mechanisms that give suPAR its prognostic value as a unique marker of chronic inflammation.