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With some big AI companies soon to go public on the stock market, the ranks of ultra-rich philanthropists in the United States look set to grow. Compared to government funding agencies, ultra-wealthy research investors tend to support projects that are higher risk and more personally relevant, with fewer strings attached. But there’s less oversight of philanthropic programmes, it’s difficult to assess their success and many are geared towards encouraging the use of the same technology the philanthropists profited from developing.

Nature | 15 min read

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Global greenhouse-gas emissions might have plateaued last year and there has been a faster-than-expected expansion of renewable energy capacity, finds the United Nations’ latest report on climate change. But without a major acceleration in emissions cuts, by mid-century average temperatures might hurtle past 2 °C — a ceiling that countries committed to in the Paris Agreement. The emissions slow-down is “definitely good news, but not good enough,” says climate scientist Bill Hare. Under current policies, scientists estimate warming to peak at 2.6 °C to 2.8 °C this century; there is also a smaller chance of warming exceeding 3.4 °C on the current trajectory, which would be catastrophic.

Nature | 8 min read

Reference: UN Environment Programme Emissions Gap Report 2026

Palaeontologists have trained a machine-learning model on a huge database of fossil records, then used it to reconstruct a timeline of changes in Earth’s biodiversity over hundreds of millions of years in unprecedented detail. The model, called OneStrata, hints at several possible challenges to big ideas about evolutionary history. For example, it suggests that three of the “Big Five” mass-extinction events were gradual declines in biodiversity, rather than the sudden cataclysms described by other reconstructions.

Nature | 7 min read

Physicists have suspended a single positron — the antimatter equivalent of an electron — near absolute zero and in a near-perfect vacuum, for months. Researchers hope to spot subtle differences between matter and antimatter that could shed light on one of physics’ greatest mysteries: why is there something rather than nothing.

Nature | 6 min read

Reference: Physical Review Letters paper

A study of more than 11,000 people with depression found that a quarter had a new subtype that makes their condition hard to treat. ‘Circadian depression’ seems to be linked to disruptions in the body’s internal clock, which could be targeted with treatments such as melatonin and light therapy. “Circadian depression is not just depression with bad sleep,” says neuroscientist and study co-author Emiliana Tonini. “There is an underlying biology that is quite distinct from other forms of depression.”

The Guardian | 5 min read

Reference: British Journal of Psychiatry paper

The ‘modern-day Jonah’ film Whalefall, based on Daniel Kraus’s 2023 novel, follows a university student who is accidentally swallowed by a sperm whale while scuba diving. Scientific advisor Joy Reidenberg, a comparative anatomist, and Ilias Foskolos, who researches deep-diving toothed whales, talk to Nature about glowing guts, stomach acids and why we probably don’t have to worry about any of this in real life.

Nature | 8 min read

Can you tell the story of your research in 60 seconds? Or maybe you can express your PhD thesis in the form of dance? If the answer to either of those questions is ‘yes’, you’re in luck.

Nature and Merck’s Science in Shorts awards are open, and there’s €5,000 up for grabs. Ditto the annual Science/AAAS Dance Your PhD contest, which could nab you up to US$2,750.

While I ponder a 1-second Nature Briefing (or perhaps a little dance?), why not send me your feedback on this newsletter? Your e-mails are always welcome at briefing@nature.com.

Thanks for reading,

Flora Graham, chief editor, Nature Briefing

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