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Scientists make inferences about a mouse’s mental health by measuring the time it takes to stop swimming.Credit: Philippe Psaila/Science Photo Library

Animal-welfare campaigners and scientists have growing concerns about a popular test in which mice or rats are dropped into a tank of water while researchers watch to see how long the animal tries to stay afloat. In theory, a depressed rodent will give up more quickly than a happy one. But mental-health researchers have become increasingly sceptical in recent years about whether the forced-swim test is a good model for depression in people.

Nature | 5 min read

Protests against the controversial Thirty Meter Telescope (TMT) have led to the shutdown of 13 observatories on Mauna Kea in Hawaii. A ruling by the state’s supreme court cleared the way for construction on the TMT to resume on 15 July, but opponents say that the telescope will further despoil a sacred mountain. Hundreds of astronomers have signed an open letter asking the state to stop arresting demonstrators and to remove police and National Guard troops from the mountain.

Nature | 4 min read

For the first time, a deep-learning algorithm has taught itself an efficient way to solve a Rubik’s cube. The program worked backwards from a solution to a given configuration to observe how closely the two are related. It repeats that process for a large number of configurations and combines those observations to determine optimal moves for solving the puzzle. The algorithm solved the cube on every trial and, in more than 60% of trials, solved the cube with the smallest possible number of moves.

Nature Research Highlights | 1 min read

Reference: Nature Machine Intelligence paper

Get more of Nature’s Research Highlights: short picks from the latest papers.

INFOGRAPHIC OF THE WEEK

FEATURES & OPINION

You hope it will never happen: losing your lab, or priceless artefacts or samples, to a fire, equipment failure or natural disaster. Researchers who have experienced explosions, floods, hurricanes and other calamities tell Nature how they moved on by diving into reconstruction, learning from the experience or even taking advantage of a blank slate to drive their research in a different direction.

Nature | 11 min read

Listen to researchers tell their stories of recovering from disaster in this week’s Nature Podcast.

The Cosmic Crisp apple has delightfully crunchy flesh, red skin speckled with star-like freckles — and a US$10.5 million marketing budget. Go deep into the scientific, agricultural and economic forces that feed into the creation of a produce superstar-in-waiting.

The California Sunday Magazine | 19 min read

BOOKS & ARTS

Barbara Kiser’s pick of the top five science books to read this week includes a saga of extinction, Tesla in his time, and explorations under the surface of skin.

Nature | 2 min read

IMAGE OF THE WEEK

Credit: Erhard Strohm

The European beewolf (Philanthus triangulum), is a solitary wasp that hunts down honey bees and leaves their bodies next to its eggs to feed its young. To keep the kids’ dinner fresh, beewolf eggs produce nitric oxide, seen here as bright yellow spots covering the dead bee. This gas kills mould fungi, ensuring that prey is preserved for when the larvae hatch. (Reference: eLife paper)

See more of the most spectacular images of the month, as selected by Nature’s photo team.