Hello Nature readers,

Today we delve into how cats purr, explore the promise of RNA rings and learn about a rare opportunity to make progress in protecting global biodiversity.

In China, where heavy rains caused massive flooding earlier this year, the extent of settlements in highly flood-prone areas more than tripled over the three decades following 1985. (Pedro Pardo/AFP via Getty)

Urban development fastest in flood plains

Countries have been building villages, towns and cities in areas with high flood risk faster than in areas less likely to be inundated by rising rivers, torrential rain, storm surges and sea-level changes. "This is a concerning trend, especially as climate change is intensifying flood disasters worldwide," says economist and study co-author Jun Rentschler. The East Asia and Pacific region had the highest proportion, more than 18%, of settlements in areas that are prone to flooding. Development in flood plains is mainly driven by scarcity of land in safer areas.

Nature | 4 min read

Reference: Nature paper

South Korea's science could face budget cuts

South Korea's scientists have been left reeling after the government proposed substantial cuts to next year's research budget. The country's spending on research - more than 4.5% of its gross domestic product - is among the highest in the world. Scientific unions and associations are joining together for the first time to protest the plan. Even if the cuts do not go ahead, the proposals have already hurt morale, says physicist Doochul Kim.

Nature | 5 min read

Cats purr without muscles or brain input

Domestic cats' (Felis silvestris catus) voice boxes contain pads of fatty tissue that slow down the vibrations of their vocal cord. This allows the cats to purr at a lower frequency than would be expected for such a small animal - something that puzzled researchers for a long time. Sustaining the sound doesn't seem to require input from muscles or the brain. Pumping air through surgically removed cat larynxes produced self-sustaining vibrations, which challenges the common explanation that purring is produced through fast, repeated muscle contraction.

Science | 5 min read

Reference: Current Biology paper

Features & opinion

RNA rings could be the next big things

RNA-based vaccines were the heroes of the COVID-19 pandemic. Their success has revved up interest in ring-shaped RNA, which is more resilient to being chewed up by enzymes in the body than is the usual linear form. This could increase its potential in vaccines, rare-disease treatments and anti-cancer agents. The first human trial, of a SARS-CoV-2 vaccine containing circular RNA, kicked off in August. Next year could see more circular RNA enter clinical trials, including in two cancer therapeutics.

Nature | 11 min read

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Spice up your bioinformatics skills with AI

Artificial-intelligence (AI) programs can speed up monotonous tasks such as data and image analysis - and the learning curve is not too steep. Here are some things to consider when taking the leap:

Some tools require little to no coding expertise, for example CellProfiler, ilastik, QuPath and CDeep3M

Learn basic coding skills with tutorials on Coursera, edX and Udacity, or live courses such as those by the European Bioinformatics Institute

Don't worry about chasing the latest technology

Connect with the community on forum.image.sc, BioStars.org or GitHub

Nature | 10 min read

Join the quiet revolution in biodiversity

A quiet revolution is taking place to incorporate the costs of biodiversity loss into economic planning. Decades of painstaking work led to a standard for measuring it all, used by 92 countries and rising. It's one bright spot in the progress towards reversing the looming crisis on land - the 15th of the 17 Sustainable Development Goals (SDGs) agreed by the United Nations. Otherwise, SDG 15 is nowhere near on track. Scientists can help by sharing their expertise with the UN Statistics Division, which is revising the international statistical standard used to measure economic activity. Have your say by 9 October.

Nature | 5 min read - part of a series of editorials about how scientists can help with a rescue plan for the SDGs

TEST YOUR PERSPECTIVE ON THE SDGS

Have you got a good grasp on our progress when it comes to the world's biggest problems? Take this quiz, based on the SDGs, to test your knowledge.

QUOTE OF THE DAY

"Young scientists, remember your humanity."

In 2015, agronomist M. S. Swaminathan harkened back to the anti-war Russell–Einstein Manifesto to encourage young scientists to work for the benefit of society. Swaminathan, one of the architects of the 'green revolution' that transformed food security in India, has died aged 98. (The Guardian | 6 min read & The New York Times | 7 min read)

Today I'm shedding a little happy tear watching Drew Weissman telling his parents that he won the Nobel Prize for his work on mRNA. "You're the product of our hearts, Drew," says his mom, "and you deserve it." Heartwarming stuff.

It would warm my heart to read your feedback on this newsletter (whether positive or critical). Please e-mail us at briefing@nature.com.

Thanks for reading,

Flora Graham, senior editor, Nature Briefing

With contributions by Katrina Krämer

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