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Raptors such as the short-toed snake eagle (Circaetus gallicus) are under threat in India.Credit: David Allemand/Nature Picture Library

India’s first major report on the state of bird populations reveals declines in hundreds of species. The report was drawn from 10 million citizen-scientist observations on the bird-spotting app eBird. Birds of prey and waterbirds seem to have been hit particularly hard owing to habitat destruction, hunting and the pet trade.

Nature | 3 min read

Reference: State of India’s Birds report

The co-director of a prestigious biology summer course has resigned after it became widely known that, several years ago, he violated the sexual-harassment policy at his home university. Warnings about biologist Richard Schneider’s past had been quietly passed around researchers involved with the residential course at the Marine Biological Laboratory in Woods Hole, Massachusetts, for years. But a widely seen tweet linking to past media coverage reignited the issue amid an atmosphere of growing concern about sexual harassment in academia.

Nature | 7 min read

Features & opinion

A powerful set of molecular tools helps synthetic biologists to assemble DNA of different sizes, from the gene to the chromosome scale. Discover more about the tools on offer, including Gibson Assembly and Golden Gate cloning.

Nature | 11 min read

Many British academics are praying that the current round of rankings is the last for the Research Excellence Framework (REF). But critics of the United Kingdom’s system for evaluating research quality should beware unintended consequences if it is abolished, argues a Nature Editorial. “A bonfire of the REF might well appeal to many, but not if the outcome leads to cuts, or reduced autonomy for institutions,” argues the editorial.

Nature | 3 min read

News & views

Why is there more matter than antimatter? An incredibly precise analysis of antihydrogen provides fresh evidence that it’s not because the physics of particles and their antiparticles are different. The gaps between energy levels in antihydrogen — the simplest antimatter atom, with one antiproton and one positron — seem to be identical to those measured in ordinary hydrogen. It’s an example of charge–parity–time (CPT) symmetry — and evidence that a violation of that symmetry probably didn’t lead to the matter-antimatter imbalance after the Big Bang.

Nature | 6 min read

Reference: Nature paper

Image of the week

A research platform floats above the Yongle blue hole, whose 130-metre-wide mouth is surrounded by coral reefs.Credit: P. Yao et al./JGR Biogeosciences

A research platform floats above the Yongle blue hole, which has a 130-metre-wide mouth surrounded by coral reefs. The yawning sinkhole in the South China Sea provides a window onto unusual ocean chemistry. Researchers collected bottles of water at various intervals and found that dissolved carbon from the depths was more than 8,000 years old. (Nature | 2 min read)