Masking, a common SARS-CoV-2 risk mitigation strategy, is controversial for children in educational settings such as childcare. A prospective survey of early childcare workers demonstrated that child masking was associated with a significant reduction in COVID-19 program closure, highlighting potential benefits of child masking in keeping childcare open, parents employed, and children learning.

Galaxies’ gas is the fuel to form new stars. The formation process stops when galaxies run out of this fuel. However, the mechanisms that cause a galaxy to run out of gas are not yet clear. We discovered a galaxy that is ejecting a large fraction of its gas, and that will quickly stop forming new stars. This ejection has likely been produced by the collision between two galaxies.

Fossil plants found in the Peruvian Andes revealed a dramatic tale of past environmental change. This transformation was a response of the rapid mountain uplift that occurred millions of years ago in this region. These findings underscore the fundamental role that the Andean uplift play shaping South American past, present and future climate.

Freshwater ecosystems are the most threatened in the world yet hardly considered in conservation planning. We show that current conservation efforts focused on terrestrial biodiversity do not guarantee protection for freshwater species. However, the solution is not far away: integrated terrestrial-freshwater conservation substantially improves freshwater protection without undermining terrestrial species.

The study of a forgotten crocodile skull collected in Libya back in 1939 suggests that the extinct Crocodylus checchiai may be the link between the Nile and the American crocodiles. This discovery would support the hypotheses of crocodiles’ journey across the ocean from Africa to America.