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Emotionally engaging forms of communication are more effective than scientific facts alone in motivating climate action, finds a review of 71 studies. Messages focused on individual responsibility had little impact — and sometimes backfired. “The emotions you feel when you watch a nature documentary, see the northern lights or witness the birth of a new animal imbue these events with meaning,” says psychologist and co-author Tobias Brosch. “They may also drive you to look better after our environment — by volunteering your time, donating or voting for climate-friendly parties.”

Nature | 7 min read

Reference: Journal of Environmental Psychology paper

Traces of mind-altering substances found in the teeth of two skeletons discovered in Indonesia could be evidence of the earliest known habitual drug use. The skeletons’ teeth showed considerable signs of wear and contained traces of the compound arecoline, which suggest that the pair regularly sucked on psychoactive betel nuts. One of the skeletons dates to 16,000–25,000 years ago, which hints that this behaviour predates betel chewing, a drug-taking method still in use today.

The Guardian | 4 min read

Reference: Science Advances paper

AI and PhDs: join a free webinar

Graduate students increasingly use artificial-intelligence tools, but many fear that using them could erode the very skills a doctorate is meant to build. In a 60-minute webinar organized by Nature’s careers team, a panel will discuss how PhD programmes and students are adapting. The live event takes place on 23 September at 14:00 UTC (15:00 BST).

Find out more about the three panellists, and how to register and submit questions in advance.

Features & opinion

Injected vaccines can raise an army of antibodies in the blood to stave off major illness, but don’t prevent infection at the points where respiratory viruses enter the body. Researchers hope that nasal vaccines could bolster protection at the moist mucosal barriers that line the respiratory tract, which could enable a person to rapidly ward off pathogens and prevent them from spreading a virus to others. A long line of failures demonstrates that developing a mucosal vaccine is a challenging task, but their promise is still enough to maintain commercial interest.

Nature | 8 min read

This video is part of Nature Outlook: Drug delivery, an editorially independent supplement produced with financial support from Taiho Oncology, Inc.

Lost luggage finds a new purpose in In the basement of miniaturized relics.

Nature | 6 min read

During the COVID-19 pandemic, researchers conducted a trial across five countries to test whether phone tutoring could keep kids learning maths when their schools were closed. They found that students who received a weekly 20-minute phone call from a tutor made big improvements in their learning. Kids who only received text messages also showed a modest improvement. The approach offers a relatively cheap way to support children’s education, say the study authors. But scaling the programme up to a national level could prove difficult, say others.

Nature Podcast | 21 min listen

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Today Leif Penguinson is exploring Okefenokee Swamp, Georgia, the largest blackwater swamp in North America. Can you find the penguin?

The answer will be in Monday’s e-mail, all thanks to Briefing photo editor and penguin wrangler Tom Houghton.

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Flora Graham, chief editor, Nature Briefing

With contributions by Jacob Smith

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