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Coloured Scanning electron micrograph of a melanoma cell that has been blasted open

Credit: The Institute of Cancer Research, London

The month’s best science images

The close-up shot above shows a cancer cell that has been cut open using an ion beam. The beam has blasted part of the cell away to reveal a cross section and has cut into the silica substrate, creating a triangular shape. Ion-beam milling allows researchers to look inside cancer cells in unprecedented detail. The image by biomedical engineer Nick Moser and cancer biologist Chris Bakal was shortlisted for the science- and medical-imaging competition run by the Institute of Cancer Research in London.

See more of the month’s sharpest science shots, selected by Nature’s photo team.

Nature | Leisurely scroll

The parrots that understand probabilities

A group of kea, a type of parrot from New Zealand, have been surprising scientists by passing a series of intelligence tests based around probabilities and social cues. Researchers found that kea can outperform monkeys, showing abilities previously seen only in great apes such as humans and chimpanzees.

Nature | 4 min video

Go behind the paper with behavioural ecologist Amalia Bastos in the Nature Ecology & Evolution Community.

Reference: Nature paper

COVID-19 coronavirus outbreak

Electron microscope image of the Novel Coronavirus

An image of the new coronavirus taken with an electron microscope.Credit: U.S. National Institutes of Health/AP/Shutterstock

What might make coronavirus so contagious

• A protein on the surface of the SARS-CoV-2 coronavirus might explain why it infects human cells so readily. Coronaviruses use a ‘spike’ protein to infect cells. A handful of genetic and structural analyses suggest SARS-CoV-2’s spike protein is activated by an enzyme found in lots of human tissues, including the lungs, liver and small intestines. That means that the virus has the potential to attack multiple organs, and it could explain some of the symptoms of the infection. Other research has shown that the spike protein binds to a particular receptor on human cells — angiotensin-converting enzyme 2 (ACE2). Both results, although early, hint at places where a treatment might target the virus. (Nature | 5 min read)

• A study originally set up to track influenza in Seattle is now at the centre of ground zero for COVID-19 in the United States. With testing in the country bogged down by problems, researchers in the Seattle Flu Study created their own diagnostic test — which revealed that the virus was spreading undetected in Washington state. Infectious-disease specialist Helen Chu, who co-leads the study, and other researchers on the ground share how they are helping the state prepare for a deluge of cases. (Nature | 8 min read)

• The US government will allocate US$8.3 billion to the country’s coronavirus response. More than $3 billion will go to the Centers for Disease Control and Prevention, the National Institutes of Health and the Food and Drug Administration for research on diagnostics, therapeutics and vaccines. Much of the rest will go to individual states for local responses. (Nature | Continuously updated)

Read the latest coronavirus news, continuously updated on Nature.

105,586

The number of known global cases of COVID-19 — across more than 100 countries — as of 8 March. (Nature | Continuously updated)

Notable quotable

“There is no evidence that we’re seeing only the tip of a grand iceberg, with nine-tenths of it made up of hidden zombies shedding virus. What we’re seeing is a pyramid: most of it is aboveground.”

Physician Bruce Aylward, who led the World Health Organization team that visited China, gives his personal insight into the success of the country’s efforts to stop the outbreak, how the virus spreads and the death rate. (The New York Times | 11 min read)

Features & opinion

Do better science: admit you’re not objective

In failing to recognize that science can be political, the scientific community risks the resurrection of dangerous ideas, argues science journalist Angela Saini, who wrote the influential 2019 book Superior: The Return of Race Science. “Geneticists today rightly treat eugenics as a laughable proposition,” says Saini. “But this ignores how these ideas manifest in the real world … The people on the receiving end of the worldview that drove eugenics understand how alive it remains.”

Nature | 5 min read

How the academic paper is evolving

In this four-part podcast series, researchers explore the stages of writing a top-notch paper. In the final episode, they delve into the article of the future, examining the rise of lay summaries, the pros and cons of preprint servers and how peer review is being crowdsourced and opened up.

Nature | 19 min listen

The indomitable Toshiko Mayeda

The seeds of Toshiko Mayeda’s chemistry career were planted in the rough ground of a US internment camp for American citizens of Japanese ancestry. Later, despite having only an undergraduate degree in chemistry, Mayeda helped to define our chemical understanding of Earth and the Solar System. In its series on unrecognized or undervalued scientists, Chemistry World explores Mayeda’s mastery of mass-spectrometry methods.

Chemistry World | 7 min read

Quote of the day

“I want to be an ambassador of hope.”

Adam Castillejo, known until now as the ‘London patient’, reveals his identity a year after he became the second ever person to be made free of HIV with a stem-cell transplant. He is still virus-free, and his doctors are calling the treatment a cure for HIV. (The New York Times)

Read more: Second patient free of HIV after stem-cell therapy (Nature, from March 2018)