Sustainability limits needed for CO2 removal

International audienceMany governments and industries are relying on future large-scale, land-based carbon dioxide (CO2) removal (CDR) to avoid making necessary steep greenhouse gas (GHG) emission cuts today (1, 2). Not only does this risk locking us into a high overshoot above 1.5°C (3), but it will also increase biodiversity loss, imperiling the Kunming-Montreal Global Biodiversity Framework (KMGBF) goals (4). Such CDR deployments also pose major economic, technological, and social feasibility challenges; threaten food security and human rights; and risk overstepping multiple planetary boundaries, with potentially irreversible consequences (1, 5, 6). We propose three ways to build on the Intergovernmental Panel on Climate Change (IPCC) analyses of CDR mitigation potential by assessing sustainability risks associated with land-use change and biodiversity loss: estimate the sustainable CDR budget based on socioecological thresholds; identify viable mitigation pathways that do not overstep these thresholds; and reframe governance around allocating limited CDR supply to the most legitimate uses

The bubble snails (Gastropoda, Heterobranchia) of Mozambique: an overlooked biodiversity hotspot

This first account, dedicated to the shallow water marine heterobranch gastropods of Mozambique is presented with a focus on the clades Acteonoidea and Cephalaspidea. Specimens were obtained as a result of sporadic sampling and two dedicated field campaigns between the years of 2012 and 2015, conducted along the northern and southern coasts of Mozambique. Specimens were collected by hand in the intertidal and subtidal reefs by snorkelling or SCUBA diving down to a depth of 33 m. Thirty-two species were found, of which 22 are new records to Mozambique and five are new for the Western Indian Ocean. This account raises the total number of shallow water Acteonoidea and Cephalaspidea known in Mozambique to 39 species, which represents approximately 50 % of the Indian Ocean diversity and 83 % of the diversity of these molluscs found in the Red Sea. A gap in sampling was identified in the central swamp/mangrove bio-region of Mozambique, and therefore, we suggest that future research efforts concentrate on or at least consider this region.publishedVersio

The twilight of the Liberal Social Contract? On the Reception of Rawlsian Political Liberalism

This chapter discusses the Rawlsian project of public reason, or public justification-based 'political' liberalism, and its reception. After a brief philosophical rather than philological reconstruction of the project, the chapter revolves around a distinction between idealist and realist responses to it. Focusing on political liberalism’s critical reception illuminates an overarching question: was Rawls’s revival of a contractualist approach to liberal legitimacy a fruitful move for liberalism and/or the social contract tradition? The last section contains a largely negative answer to that question. Nonetheless the chapter's conclusion shows that the research programme of political liberalism provided and continues to provide illuminating insights into the limitations of liberal contractualism, especially under conditions of persistent and radical diversity. The programme is, however, less receptive to challenges to do with the relative decline of the power of modern states

Constitutivism

A brief explanation and overview of constitutivism

A review of trabecular bone functional adaptation: what have we learned from trabecular analyses in extant hominoids and what can we apply to fossils?

Many of the unresolved debates in palaeoanthropology regarding evolution of particular locomotor or manipulative behaviours are founded in differing opinions about the functional significance of the preserved external fossil morphology. However, the plasticity of internal bone morphology, and particularly trabecular bone, allowing it to respond to mechanical loading during life means that it can reveal greater insight into how a bone or joint was used during an individual's lifetime. Analyses of trabecular bone have been commonplace for several decades in a human clinical context. In contrast, the study of trabecular bone as a method for reconstructing joint position, joint loading and ultimately behaviour in extant and fossil non-human primates is comparatively new. Since the initial 2D studies in the late 1970s and 3D analyses in the 1990s, the utility of trabecular bone to reconstruct behaviour in primates has grown to incorporate experimental studies, expanded taxonomic samples and skeletal elements, and improved methodologies. However, this work, in conjunction with research on humans and non-primate mammals, has also revealed the substantial complexity inherent in making functional inferences from variation in trabecular architecture. This review addresses the current understanding of trabecular bone functional adaptation, how it has been applied to hominoids, as well as other primates and, ultimately, how this can be used to better interpret fossil hominoid and hominin morphology. Because the fossil record constrains us to interpreting function largely from bony morphology alone, and typically from isolated bones, analyses of trabecular structure, ideally in conjunction with that of cortical structure and external morphology, can offer the best resource for reconstructing behaviour in the past

Philosophy of action

The philosophical study of human action begins with Plato and Aristotle. Their influence in late antiquity and the Middle Ages yielded sophisticated theories of action and motivation, notably in the works of Augustine and Aquinas.1 But the ideas that were dominant in 1945 have their roots in the early modern period, when advances in physics and mathematics reshaped philosophy

AVONET: morphological, ecological and geographical data for all birds

Functional traits offer a rich quantitative framework for developing and testing theories in evolutionary biology, ecology and ecosystem science. However, the potential of functional traits to drive theoretical advances and refine models of global change can only be fully realised when species‐level information is complete. Here we present the AVONET dataset containing comprehensive functional trait data for all birds, including six ecological variables, 11 continuous morphological traits, and information on range size and location. Raw morphological measurements are presented from 90,020 individuals of 11,009 extant bird species sampled from 181 countries. These data are also summarised as species averages in three taxonomic formats, allowing integration with a global phylogeny, geographical range maps, IUCN Red List data and the eBird citizen science database. The AVONET dataset provides the most detailed picture of continuous trait variation for any major radiation of organisms, offering a global template for testing hypotheses and exploring the evolutionary origins, structure and functioning of biodiversity

The totality of soft-states in a neo-classical nematic elastomer

The remarkable ability of nematic elastomers to exist in multiple stable equilibrium configurations in the absence of force and energy cost is known as soft elasticity. Here, we determine all of the soft states that are possible in two particular classes of nematic elastomers: the neo-classical nematic elastomers, which have received considerable recent attention; and a natural theoretical generalization, which we call the Mooney nematic elastomers. For both of these classes, the soft states are minimizers of the free energy. Our starting point is to develop a nonlinear continuum theory for nematic elastomers, the constitutive framework of which includes the special classes noted above. This theory is based on two distinct force balances???one arising from the macroscopic deformation and the other from the nematically-induced distortion of the polymer molecules???and allows for coexistent isotropic, uniaxial, and biaxial phases. These balances are supplemented by a principle of dissipation imbalance, a principle that in conjunction with invariance requirements is used to obtain restrictions on constitutive equations.published or submitted for publicationis peer reviewe

On internal constraints in continuum mechanics

When a body is subject to simple internal constraints, the deformation gradient must belong to a certain manifold. This is in contrast to the situation in the unconstrained case, where the deformation gradient is in an element of the open subset of second-order tensors with positive determinant. Commonly, following Truesdell and Noll, modern treatments of constrained theories start with an a priori additive decomposition of the stress into reactive and active components with the reactive component assumed to be powerless in all motions that satisfy the constraints and the active component given by a constitutive equation. Here, we obtain this same decomposition automatically by making a purely geometrical and general direct sum decomposition of the space of all second-order tensors in terms of the normal and tangent spaces of the constraint manifold. As an example, our approach is used to recover the familiar theory of constrained hyperelasticity.published or submitted for publicationis peer reviewe