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The SARS-CoV-2 virus almost certainly originated in bats, then probably passed to an intermediate animal, which spread it to people. But it’s been very difficult to identify that animal — or to completely rule out the unsubstantiated idea that the virus escaped from a laboratory. Pinpointing the source of SARS-CoV-2 would require extensive sampling of coronaviruses in wildlife and livestock, and could take years.
A huge artificial plateau that is 1.4 kilometres long and 10–15 metres high has been discovered in Mexico. Archaeologists spotted the monumental construction from the air using lidar, a remote-sensing method that maps the ground using lasers. Dubbed Aguada Fénix, the extensive structure was built between 1000 and 800 BC, and precedes the peak of the Maya empire by more than a millennium.
The Lancet and The New England Journal of Medicine (NEJM) have retracted two separate studies that relied on de-identified electronic health records from a company called Surgisphere. The Lancet study raised safety concerns about the malaria drug hydroxychloroquine as a COVID-19 treatment, which prompted some regulators to temporarily pause trials of the drug. The NEJM study found no evidence that blood-pressure medications were harmful for people with COVID-19 and underlying cardiovascular disease. The authors requested that the papers be retracted after questions were raised about the underlying data, and Surgisphere refused to provide them for legal and confidentiality reasons.
A third study using Surgisphere data, uploaded to and then removed from social-sciences preprint server SSRN, has contributed to enthusiasm for the antiparasitic drug ivermectin in South America. “Who retracts this ivermectin ghost in Latin America?” asks global-health researcher Carlos Chaccour. “There’s no high-profile journal saying this was wrong.”
Features & opinion
When fruit flies endure sleeplessness, cells in their guts accumulate toxic molecules that break down their DNA. Similar toxins were spotted in sleep-deprived mice. And when the sleepless flies were given antioxidants that prevent such build-up, they reached a normal fly life span. “‘They’re alive!’ And not only were they alive, they looked good,” says developmental neuroscientist Dragana Rogulja. The results suggest that although most sleep studies focus on the brain, lack of sleep kills by damaging other organs.
Lab-grown skin has, up until now, had something missing: hair. Stem-cell researcher Karl Koehler tells the Nature Podcast how he and his colleagues made the leap — which could someday lead to skin grafts that include many more of the cells, glands, nerves and other components found in normal skin. “We are starting from pluripotent stem cells — these are cells that can become any cell in the body,” Koehler says. “We’re essentially recreating the entire developmental process of the skin.”
Books & culture
Information overload can make you feel numb or cause anxiety, says Heather Houser, co-director of a climate-resilience project in the United States and author of a new book, Infowhelm. For scientists, the emotional impact of studying topics such as ecological collapse can be devastating — yet they must maintain professional detachment. “I think the arts are a great way to allow all these other aspects of understanding and processing, as a person, to come into the narrative,” says Houser.
The shifting climate means that we must allow — and assist — people, plants and animals who are forced to relocate to survive, argues a book by journalist Sonia Shah. Shah draws on affecting anecdotes and reflects on animal movements — both natural and human-caused — to explore our attitudes in advance of the vast human migration that will be caused by climate change. “The altered communities that result won’t just be different, they’ll often be better adapted to thrive in our warming world,” writes reviewer Emma Marris.
Where I work
Working staggered shifts to respect social distancing, Christian Happi and his team perform PCR on human-tissue samples to detect infectious pathogens. The molecular biologist has deployed his lab in Ede, Nigeria, against the current pandemic. “People might have thought that this work was impossible in Africa,” he says, “but we are demonstrating that the continent’s scientists can generate crucial data in the global fight against COVID-19.” (Nature | 3 min read)
Today, our aquatic explorer Leif Penguinson is drying off among the spiny treasures of the Huntington Library Desert Garden in California. Can you spot the penguin?
The answer will be in Monday’s e-mail, all thanks to Briefing photo editor and penguin wrangler Tom Houghton.
With contributions by Nicky Phillips, Smriti Mallapaty, David Cyranoski and Davide Castelvecchi