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The team found more than 100 fossils of the tiny creatures in the outback in South Australia.Sohail Wasif/UCR

Tiny fossil has oldest known rear-end

A fossil the size of a grain of rice appears to be the earliest known bilaterian, the group of animals with two-sided symmetry, two openings and a through-gut. The group includes all vertebrates — including us — and many invertebrate groups. More than 100 Ikaria wariootia and their burrowing tracks were found in South Australia and were dated to more than 555 million years ago. “One major difference with a grain of rice is that Ikaria had a large and small end,” says palaeobiologist Scott Evans. “This may seem trivial but that means it had a distinct front and back end, which is the kind of organisation that leads to the variety of things with heads and tails that are around today.”

The Guardian | 5 min read

Reference: PNAS paper

400 deaths from bushfire smoke in Australia

Thick smoke from Australia’s devastating bushfire season is estimated to have killed more than 400 people. Several thousand more people ended up in hospital with respiratory or heart problems linked to the haze. Bushfire smoke affected almost 80% of the country’s 25 million people between October and late January, reveals the first study to examine the health effects of the blazes. Thirty-three people were killed in incidents directly related to the fires.

Nature | 2 min read

Racial discrepancies in voice-recognition AI

Speech-recognition software by leading technology companies is worse at identifying words spoken by African American people than those spoken by white Americans. Computer scientists tested algorithms by Amazon, Apple, Google, IBM and Microsoft with recordings of black people who live in predominantly black communities on the US East Coast and white people who live in mostly white areas in California. The systems made mistakes when transcribing speech 35% of the time for black speakers compared with 19% for white speakers.

New York Times | 5 min read

Reference: PNAS paper

COVID-19 coronavirus outbreak

Staff members in protective clothing spray disinfectant at Wuhan Railway Station

Travel restrictions in Wuhan will be lifted from 8 April.Credit: AFP/Getty

PCR, serological, CRISPR: the diagnostic tests

• Most testing for COVID-19 is currently done on viral genetic material from nose and throat swabs, using a workhorse tool of molecular biology called reverse transcription polymerase chain reaction (RT-PCR). The next big goal is to develop a serological test — one that can detect antibodies in someone who has already recovered. Prominent CRISPR researchers are also working on using the gene-editing technique to make faster, more accurate tests. Of course, the impact of tests depends on how authorities use them — an area where some countries, notably the United States, have stalled. (Nature | 6 min read)

Read more: Continuously updated list of the tests in commercial development and in-depth analysis from Nature Biotechnology.

• The United Kingdom is implementing a stringent shutdown to prevent the spread of the coronavirus, joining other nations that have put in place unprecedented rules to fight the pandemic. “The time has now come for us all to do more,” said Prime Minister Boris Johnson in a broadcast yesterday. (Nature | Continuously updated)

• The malaria drug chloroquine, which is being trialled as a potential treatment for COVID-19, has long been used in nanomedicine for studying nanoparticle uptake by cells. Three nanomedicine researchers share their insights into how, exactly, chloroquine might affect the virus SARS-CoV-2. (Nature Nanotechnology | 8 min read)

• ProMED is a low-tech service run by public-health researchers that specializes in capturing — and vetting — the online chatter that gives early clues to an outbreak, including the earliest sightings of COVID-19. On a shoestring budget, the website and email list offers widely respected information that supports slower-moving, more formal epidemiology. (Wired | 8 min read)

• The eminent London School of Hygiene & Tropical Medicine is offering a free 3-week online course on COVID-19 and its implications. It has no prerequisites, world-leading lecturers and translations in Chinese, Spanish, Portuguese, French and Italian. (London School of Hygiene & Tropical Medicine | 4 hours per week)

Read the latest coronavirus news, continuously updated on Nature.

332,935

The number of COVID-19 coronavirus infections worldwide, as of yesterday. World Health Organization director-general Tedros Adhanom Ghebreyesus said in a press briefing that it took 67 days from the first reported case to reach the first 100,000 cases, 11 days after that to reach 200,000 and just another 4 days to top 300,000 infections. (Nature | Continuously updated)

Features & opinion

How to solve the global challenge of climate change

Climate change demands action: humanity must shift from persistent destruction to intentional regeneration. So, how best to make that happen? Two new books give very different answers. In one, the solution lies exclusively with nation states and their protection of security and self-interest. The other, by Christina Figueres, architect of the Paris Agreement, expects a global-scale spirit of shared endeavour to harness the collective power of governments, corporations and individuals.

Nature | 4 min read

Facebook: share more with researchers

Smarting from the Cambridge Analytica debacle in 2018, Facebook promised a research initiative to give academics access to its data. But the data that the tech behemoth has provided are nearly useless for answering many research questions, and are far inferior to what Facebook gives private companies, argues political-data-science researcher Simon Hegelich.

Nature | 4 min read

Image of the week

A jumble of carbon nanotubes that resembles spaghetti

Changyong Cao, Michigan State University

Carbon nanotubes placed on a stretchy substrate create a flexible supercapacitor that remains fully functional even when deformed to eight times its original size. (United Press International | 5 min read)

Reference: Matter paper

Quote of the day

“We’ll keep working on results. One of them may be from E.T. We don’t know.”

Dan Werthimer, chief scientist of the SETI@home project, explains why the crowdsourced alien-searching screensaver is taking a break after 21 years. The dwindling team of scientists who run the programme say they need to spend more time analysing the 20 billion events flagged by the system, and less time keeping servers up and running. (The New York Times | 8 min read)