Daily briefing: Mysterious spike in ozone-killing chemicals is over

Rogue CFC emissions have halted after scientists raised the alarm. Plus, a WHO team’s visit to China has left some questions unanswered and prozac pollution can zombify fish.

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Researchers in face masks cluster behind a blue barrier.

Members of the World Health Organization team investigating the origin of the virus SARS-CoV-2 visit the closed Huanan seafood market in Wuhan, China.Credit: Hector Retamal/AFP/Getty

WHO origins search leaves open questions

The hunt for the COVID pandemic’s origins must continue, say scientists, after a World Health Organization (WHO) team’s visit to China didn't find answers to key questions about how the coronavirus started infecting people. At a press briefing on 9 February in Wuhan, China, members of the WHO team reported a series of conclusions from their month-long investigation in the country. The researchers largely discounted the controversial idea that the virus accidentally leaked from a laboratory, and suggested that SARS-CoV-2 most likely first passed to people from an intermediate animal — already a leading hypothesis among researchers.

Nature | 7 min read

Rogue CFC emissions halted following alarm

A mysterious spike in ozone-destroying chemicals has essentially disappeared after scientists raised the alarm in 2018. Most of the illegal emissions of trichlorofluoromethane, or CFC-11, were tracked to China, which committed to cracking down on the pollution. The most likely source was the manufacture and use of foam insulation. Assuming the current trend continues, the damage to the ozone layer from several years of illegal emissions will be negligible, say scientists.

Nature | 4 min read

Reference: Nature paper 1 & Nature paper 2

Prozac pollution can zombify fish

Long-term exposure to the antidepressant Prozac makes guppies act more alike, which could leave fish populations more vulnerable to threats. Human drugs often end up washing from sewers into rivers, which can alter animals’ natural behaviours. Researchers studied the behaviour of up to six generations of guppies that lived in tanks of water laced with different but realistic levels of Prozac. When placed in a new tank, most fish that grew up drugged were moderately active and ‘average’, whereas the drug-free fish ranged from active to lazy. The next step is to figure out the impacts of the zombie-like suppression of differences among drug-exposed fish in the wild.

Science | 5 min read

Reference: Proceedings of the Royal Society B paper

Destination, Mars!

This week, both the United Arab Emirates’ Mars Hope orbiter and China’s Tianwen-1 rover successfully entered Mars orbit. On 18 February, NASA’s Perseverance rover will aim to land in Mars’s Jezero Crater.

The Hobe Probe with extended solar panels and central satellite dish in a clean room

Hope with its solar panels extended.Credit: MBRSC

How the UAE built a Mars mission

With the successful arrival of its Hope spacecraft into Mars orbit this week, the United Arab Emirates (UAE) became the first Arab nation to achieve an interplanetary mission. It launched its orbiter a mere six years after the nation announced the project, which it hopes will help to transform the country’s oil economy into a knowledge economy. Fundamental to the mission was tapping the expertise of seasoned US engineers, who helped to build the craft and train their UAE counterparts. The mission’s Emirati team personifies the aspiring scientists that the project hopes to inspire: at the project’s outset, the average age of the engineers was 27, and women make up 80% of its scientists. If the UAE can pull off that economic transformation, it would be an even greater prize than getting to Mars, says Sarah Al Amiri, the science lead for the project and the country’s minister for advanced sciences. “How we get there is even more important,” she says.

Nature | 13 min read (from July)

Backstory: from a <Emphasis Type="Italic">Nature</Emphasis> reporter’s perspective

The UAE Hope orbiter is not the most advanced bit of technology on Mars, and it’s certainly not a rival to the US and Chinese craft arriving at the same time. But the fact that the country has launched an interplanetary mission at all is amazing: seven years ago, it didn’t have a space agency, and it hadn’t awarded a single PhD before 2010. How the UAE got there wasn’t magic — they hired experienced US engineers as partners. But the Emirati plan to learn on the job in order to build up science in the country, while at the same time collecting Martian data that benefits the whole scientific community, I found really impressive.

Elizabeth Gibney, Nature senior reporter

Notable quotable

“Lovers are waiting for 14th February. Legends are waiting for 18th February.”

Engineer Swati Mohan, the guidance, navigation and control operations lead for NASA’s Perseverance rover, shares a Mars-themed Valentine’s Day card from her spouse in anticipation of next week’s landing. (Twitter)

Features & opinion

Science diversified: Starting young

Scientists at the Francis Crick Institute in London are going back to school. They are spending time at a nearby primary school, which is rich in social and ethnic diversity, to challenge scientific stereotypes. “I was the first person in my family to go to university and end up working in science,” says molecular virologist Clare Davy, who is the education manager at the Crick. “I've always been interested in how I made that journey, and how I can help other young people to get there as well.”

Nature Careers Podcast | 28 min listen

Milestones in genomic sequencing

Explore a timeline of DNA sequencing, one of the most influential tools in biomedical research. It goes from the development of Maxam–Gilbert sequencing and Sanger sequencing in 1977 — which helped Walter Gilbert and Frederick Sanger to win the 1980 Nobel Prize in Chemistry — to the publication of the first draft of the human genome 20 years ago this week, and beyond.

Nature | Leisurely scroll

This article is editorially independent and produced with financial support from Illumina.

Infographic of the week

A survey of thousands of people in 15 countries suggests that an increasing proportion of people are willing to be immunized against COVID-19. “For the first time since the pandemic began, I can sense that optimism is spreading faster than the virus,” says behavioural scientist Sarah Jones. But the results for some individual countries paint a more complicated picture — in particular those that have a history of vaccine mistrust, such as France and Japan.

Nature | 4 min read

Reference: Global attitudes towards COVID-19 vaccine report

Happy International Day of Women and Girls in Science! Today I’m excited that the campaign to raise a statue to pioneering palaeontologist Mary Anning (and her beloved dog Tray) has hit its main fundraising goal. To support the campaign, started by 11-year old Evie Swire, check out the fossil silent auction happening today on its Twitter page.

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Flora Graham, senior editor, Nature Briefing

With contributions by Elizabeth Gibney

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