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Millipede fossil

Kampecaris obanensis was about 2.5 centimetres long with a segmented body. It resembled modern millipedes, but was a member of an extinct group and is not ancestral to millipedes alive today.British Geological Survey

The oldest land animal ever found

An inch-long critter similar to a millipede looks to be the oldest animal known to have lived on land. Fossil imprints of Kampecaris obanensis from the island of Kerrera in Scotland have been radiometrically dated to around 425 million years ago, in the Silurian period. The arthropod probably fed on decomposing plants on a lakeside. Even earlier land animals, from the Cambrian era, are known to have existed, but only indirectly, from their tracks.

CBC | 3 min read

Source: Historical Biology paper

COVID-19 coronavirus outbreak

Cartoon showing the profile of a student on the left and on the right a sliding puzzle made up of the student

Credit: The Project Twins

Universities will never be the same

In the first of our series on science after the pandemic, Nature explores how the crisis could alter academia. Universities are confronting long-standing challenges in higher education, such as skyrocketing tuition costs, fragile finances and perceptions of elitism — and some of the resulting changes could be permanent.

Nature | 9 min read

Hydroxychloroquine study questioned

Last week, the World Health Organization (WHO) and regulators in the United Kingdom, France and Australia paused the testing of hydroxychloroquine as a COVID-19 treatment because of safety concerns. A large observational study published in The Lancet linked the antimalarial drug to an elevated risk of death and abnormal heart rhythms when used as a coronavirus therapy. Now the study itself is under scrutiny: 120 researchers have signed a letter to the journal highlighting concerns about the quality of the data and its analysis. Researchers are worried that hydroxychloroquine’s bad press will dissuade people from joining further trials — leaving questions about the drug unanswered.

Nature | 7 min read

Scientists probe risk from infected animals

Researchers are calling for extensive sampling of pets, livestock and wildlife to improve understanding of the risk that infected animals might spark new outbreaks. Roughly a dozen animals are known to be susceptible to the virus, but there have been only two reported cases of animals — both of which were minks — passing it to people. SARS-CoV-2 most likely originated in bats, and we don’t yet know whether other animals were involved in its journey to people.

Nature | 5 min read

Notable quotable

“Fuss over your fancy sourdough bread. Help your unpaired socks reunite with their soulmates. Grieve for your losses, whatever they may be. Cut yourself some slack.”

Don’t suggest, even jokingly, that now is the time for scientists to churn out their best work, says neuroscientist Daphne Ling. (Nature | 3 min read)

Coronavirus research highlights: 1-minute reads

People with COVID-19 are unlikely to spread the new coronavirus if more than eight days have passed since their symptoms began. Researchers cultured monkey cells with 90 human samples that had tested positive for SARS-CoV-2 RNA. Samples collected more than eight days after a person’s symptoms began did not infect the cells — suggesting that people who test positive for viral RNA are not necessarily infectious.

Reference: Clinical Infectious Diseases paper

The nose could be the body’s entry point for COVID-19 infections. Researchers tracked the ease with which the coronavirus infects various cell types in the respiratory tract. They found a gradient of infectivity that decreases from the upper to the lower respiratory tract: the most easily infected cells are in the nasal cavity, and the least easily infected are deep in the lungs.

Reference: Cell paper

Genetic analysis of more than 200 SARS-CoV-2 genomes from people across Israel show that only 1–10% of infected people caused 80% of the next wave of cases. The results illustrate the power of ‘superspreaders’ in viral transmission.

Reference: medRxiv preprint (not yet peer reviewed)

Get more of Nature’s continuously updated selection of the must-read papers and preprints on COVID-19.

Features & opinion

If we can make it there, we’ll make it anywhere

In 2010, the century-old Empire State Building underwent a “deep energy retrofit” that cut its emissions by 40%. The US$31.1 million overhaul brought savings of more than $4 million per year. Owners aim to cut an additional 40% in the decade to come. “If we can prove it works here, then it can work anywhere,” says Dana Robbins Schneider, the building’s director of energy and sustainability. The Washington Post uses interactive graphics to break down exactly how they did it.

The Washington Post | 16 min read

#BlackBirdersWeek celebrates being #BlackInNature

People are coming together on Twitter and Instagram to boost the signal of Black scientists, birders and outdoor explorers in the United States. “For far too long, Black people in the United States have been shown that outdoor activities, such as birding, are not for us,” said naturalist Corina Newsome in a video announcing the project: “We’ve decided to change that narrative.”

BirdWatching Daily | 3 min read

Quote of the day

“The society’s statement is a heartfelt bridge from a science community to the broader community.”

Meteorologist Marshall Shepherd, the former president of the American Meteorological Society, commends an anti-racism statement from the group and reflects on his experiences as an African American scientist. (Forbes | 6 min read)