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Shards of a purple crystal on a table.

Pure crystals of LK-99, synthesized by a team at the Max Planck Institute for Solid State Research in Stuttgart, Germany.Credit: Pascal Puphal

Impurity quashes superconductivity claim

LK-99, reportedly the first-ever room-temperature superconductor, is not one after all. Dozens of replication efforts have shown that impurities in the material were responsible for properties that were similar to those exhibited by superconductors — a sharp drop in electrical resistivity and levitation over a magnet. “I think things are pretty decisively settled at this point,” says physicist Inna Vishik.

Nature | 8 min read

Science helped kids to win climate trial

On Monday, a Montana court ruled that the state’s Environmental Policy Act, which prohibits considering the climate impact of proposed energy projects, violates the “right to a clean and healthful environment” in the state’s constitution. Attorney Julia Olson, who represented the group of young plaintiffs, calls it a “truly historic” win that could pave the way for a court-ordered shift away from fossil fuels nationwide. Science was foundational to their case, says Olson. “We heard from many of our experts that it was such an empowering experience to be able to present the science in the court of law.”

Nature | 5 min read

Read more: Climate science is supporting lawsuits that could help save the world (Nature | 11 min read, Nature paywall — Get help logging in with your institution’s subscription. Or try the new Nature+ subscription for immediate online access to Nature and other Nature journals.)

Iceman Ötzi was balding and dark-skinned

Ötzi the Iceman, the iconic 5,300-year-old mummy found in the Alps in 1991, was not the pale, long-haired man who he is often depicted to be. Improved DNA analysis reveals that Ötzi had much more melanin in his skin and probably had male-pattern baldness. It also showed that his suspected steppe ancestry — from people hailing from eastern Europe and central Asia — probably stemmed from modern DNA contamination. Instead, Ötzi had Anatolian-farmer ancestry.

Nature | 4 min read

Reference: Cell Genomics paper

Melting glaciers create new ecosystems

Glacier shrinkage will reveal vast new ecosystems in need of protection. Even in the most optimistic greenhouse-gas emissions scenario, melting glaciers could expose an area the size of Nepal by the end of the century, an analysis has found. That exposure more than doubles in a high-emissions scenario. “This could be one of the largest ecosystem changes on our planet,” says glaciologist and study co-author Jean-Baptiste Bosson. These areas, many of which are currently unprotected, could provide important habitats for carbon-storing plants and threatened animals.

Nature | 4 min read

Get the expert view from ecologist Nicolas Lecomte in the Nature News & Views article (7 min read, Nature paywall)

Reference: Nature paper

Features & opinion

The quest to map the mouse brain

“In order to have a fundamental understanding of the brain, we really need to know how many different types of cells there are, how they are organized and how they interact with each other,” explains biophysicist Xiaowei Zhuang. Scientists are combining single-cell sequencing with methods to map the location of gene expression to create the most comprehensive atlases of the mouse brain — and they have unravelled the brain’s extraordinary cellular diversity in the process. “From a therapeutics perspective, there’s a huge opportunity here to learn how these different cell types affect cognition, mood, but also physiology,” says neuroscientist Evan Macosko.

Nature | 11 min read

Why reducing inequality is so hard

In 2009, The Spirit Level, a book by epidemiologists Richard Wilkinson and Kate Pickett lit a fire under world leaders inspired by its analysis of the benefits of reducing economic inequality. But that objective — enshrined as United Nations Sustainable Development Goal 10 — is slipping further away. There is some good news: overall income inequality between countries is dropping. But income inequality within countries is rising and workers around the world are keeping a smaller slice of the economic pie that they produce. A Nature editorial examines what’s gone wrong and how to fix it.

Nature | 6 min read

How laziness helps to build collaborations

“I am a firm believer in ‘weaponized laziness’ — finding ways to work smarter rather than harder,” writes Beth Cimini, who works in bioimage analysis. One outcome is a spreadsheet template for tracking the dozens of collaborators on large projects. It simplifies such busy work, allowing users to choose from a standardized list of author contributions to research. “The best collaborations that I’ve been a part of have been ones in which systems were in place to allow anyone on the team to pop in at any time, see what was going on and what needed to be done, and lend a hand,” she writes.

Nature | 6 min read

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