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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.
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.
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.
Reference: Proceedings of the Royal Society B paper
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.
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.