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Artist's impression of a Spinosaurus head and tail

Reconstruction of Spinosaurus in life: long, narrow jaws with conical teeth, and a tail adapted for aquatic locomotion.Davide Bonadonna

A swimming dinosaur

A new fossil of one of the most unusual dinosaurs, Spinosaurus aegyptiacus, suggests it was a “river monster” powered by a fin-like tail. A new fossil found in Morocco has revealed shockingly long spines on the dinosaur’s tail that could have made it work like a giant fin. Hydrodynamic tests with plastic reconstructions of various tail shapes showed that the spinosaurus’s newt-like appendage would produce much more thrust than the tails of other dinosaurs. Spinosaurus aegyptiacus was probably even bigger than Tyrannosaurus rex, and the only other skeleton ever found was destroyed in the Second World War, says palaeontologist Nizar Ibrahim.

Nature | 5 min video

Reference: Nature paper

US patent office: AIs can’t be inventors

The US Patent and Trademark Office has ruled that artificial-intelligence (AI) systems cannot be credited as inventors. The case was raised in response to patent applications for a food container and a flashing light, both created by software called DABUS. The organization behind it was not arguing that an AI should own intellectual property, only that it should be listed as an inventor. But patent law clearly refers to humans, using pronouns such as ‘he’ or ‘she’, the agency concluded. The UK and European patent offices reached similar conclusions last year.

The Verge | 3 min read

COVID-19 coronavirus outbreak

Hopeful signs from largest remdesivir trial

The largest and most rigorous clinical trial yet of the antiviral medicine remdesivir against the coronavirus raises hopes that the drug could shorten the time to recovery. Yesterday, US National Institute of Allergy and Infectious Diseases director Anthony Fauci announced that the trial of more than 1,000 people showed that those taking remdesivir recovered in 11 days on average, compared with 15 days for those on a placebo. Results from other trials of the drug had been inconclusive. The full results of this study have yet to be published.

“Although a 31% improvement doesn’t seem like a knockout 100%, it is a very important proof of concept,” Fauci said. “What it has proven is that a drug can block this virus.” A flood of small trials for various drugs has yet to convincingly show any that have boosted survival in people with COVID-19.

Nature | 5 min read

Why the pandemic thwarts our understanding

The coronavirus pandemic is “a problem that is now too big for any one person to fully comprehend”, argues science journalist Ed Yong in a long read about the factors in play. We struggle to master knowledge that is new to many of us: the definition of a ‘coronavirus’. The characteristics of this specific one, SARS-CoV-2, and the disease it causes, COVID-19. What the research on treatment and vaccines really means, and which experts and self-appointed experts we can trust. And how we can parse misinformation, shifting public-health advice and the uncertainty inherent in a fast-moving scientific landscape.

The Atlantic | 26 min read

How the coronavirus mutates and spreads

Some of the history of the SARS-CoV-2 virus is recorded in its mutations. In this infographic-packed feature, follow the journey of the virus’s progress from Wuhan, China, to everywhere by tracing tiny variations in its RNA.

The New York Times | 7 min read

When disinfecting goes wrong

With people eager to clean and disinfect during the outbreak, accidental poisonings have spiked in the United States. Almost two-thirds of the incidents involved bleach, which can create a toxic gas when mixed with vinegar or other cleaning agents. Chemistry World breaks down exactly what happens when mixtures go wrong — and what to do if you detect the hissing, heat or bubbling that indicates a potential problem.

Chemistry World | 6 min read

Notable quotable

“This is not a question of demanding charity. African countries have funds to pay for reagents but cannot buy them.”

An ‘every country for itself’ run on COVID-19 tests has shoved Africa out of the diagnostics market, warns Africa CDC head John Nkengasong. (Nature | 4 min read)

Infographic of the week

A graphic that shows how viral vectors containing coronavirus genes can be used in a vaccine.

There are at least eight types of vaccine being tried against the coronavirus, and they rely on different viruses or viral parts. Around 25 research groups say they are working on the type shown above — viral-vector vaccines. Read Nature’s full graphical guide to how all the types work. (Nature | 8 min read)

Quote of the day

“There’s no better time than now to get in touch with the people you used to know.”

Reconnecting with dormant contacts can be helpful, inspiring, and fun — and not as awkward as we might fear, says organizational psychologist Adam Grant. He even suggests an opening line. (The New York Times | 5 min read)