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Observations of individual massive stars, super-luminous supernovae, gamma-ray bursts, and gravitational wave events involving spectacular black hole mergers indicate that the low-metallicity Universe is fundamentally different from our own Galaxy. Many transient phenomena will remain enigmatic until we achieve a firm understanding of the physics and evolution of massive stars at low metallicity (Z). The Hubble Space Telescope has devoted 500 orbits to observing ∼250 massive stars at low Z in the ultraviolet (UV) with the COS and STIS spectrographs under the ULLYSES programme. The complementary X-Shooting ULLYSES (XShootU) project provides an enhanced legacy value with high-quality optical and near-infrared spectra obtained with the wide-wavelength coverage X-shooter spectrograph at ESO’s Very Large Telescope. We present an overview of the XShootU project, showing that combining ULLYSES UV and XShootU optical spectra is critical for the uniform determination of stellar parameters such as effective temperature, surface gravity, luminosity, and abundances, as well as wind properties such as mass-loss rates as a function of Z. As uncertainties in stellar and wind parameters percolate into many adjacent areas of astrophysics, the data and modelling of the XShootU project is expected to be a game changer for our physical understanding of massive stars at low Z. To be able to confidently interpret James Webb Space Telescope spectra of the first stellar generations, the individual spectra of low-Z stars need to be understood, which is exactly where XShootU can deliver.

Silva et al. (Land Use Policy, 21 July 2020) offer an assessment of the links between deforestation, livestock production and exports in Brazil. Their analysis, based on relative changes in beef production and pasture area across the whole of Brazil, showed an “apparent decoupling of the link between beef production and deforestation in Brazil”. In reanalysing these links, we find that Silva et al. underestimate the strong, positive and significant associations between Brazilian livestock production and deforestation. Moreover, despite focusing the title, abstract and the beginning of their manuscript on the Amazon, their analyses are conducted at the national level, and fail to recognise marked differences in the development trajectories of Brazilian biomes, and that most of the recent pasture expansion in Brazil has replaced Amazonian forests. To progress any debate and aid decision-making regarding land-use changes in the Amazon, a region often in the spotlight and subjected to many debates that lack evidence, scientists must be open and scrupulous with their data sources and analyses. © 2020

Silva et al. (Land Use Policy, 21 July 2020) offer an assessment of the links between deforestation, livestock production and exports in Brazil. Their analysis, based on relative changes in beef production and pasture area across the whole of Brazil, showed an “apparent decoupling of the link between beef production and deforestation in Brazil”. In reanalysing these links, we find that Silva et al. underestimate the strong, positive and significant associations between Brazilian livestock production and deforestation. Moreover, despite focusing the title, abstract and the beginning of their manuscript on the Amazon, their analyses are conducted at the national level, and fail to recognise marked differences in the development trajectories of Brazilian biomes, and that most of the recent pasture expansion in Brazil has replaced Amazonian forests. To progress any debate and aid decision-making regarding land-use changes in the Amazon, a region often in the spotlight and subjected to many debates that lack evidence, scientists must be open and scrupulous with their data sources and analyses. © 2020