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Illustration of birds on a beach.

Artist’s reconstruction of the last known toothed bird, Janavis finalidens.Credit: Phillip Krzeminski

Beak fossil upends bird evolutionary tree

A 67-million-year-old beak bone has upended the evolutionary tree of life for birds. Most modern birds have flexible bony palates that allow them to move their upper beak independently of their skull. Just a few — including emus, ostriches and kiwis — have fused palates and fixed beaks. It had been assumed that the ancestors of all modern birds were like these ‘ancient-jawed’ palaeognaths. But a tiny bone encased in rock suggests that flexible jaws came first.

Nature | 4 min read

Reference: Nature paper

Promising Alzheimer’s drug faces safety questions

Published results now confirm promising news, announced in a press release in September, that an experimental Alzheimer’s drug slowed the rate of cognitive decline for people in a clinical trial by 27%. Lecanemab is a monoclonal antibody designed to clear from the brain clumps of the protein amyloid-β, which many think are a root cause of Alzheimer’s. But there have also been media reports that lecanemab might have contributed to the deaths of two people who participated in the trial — adding to an ongoing debate over whether the experimental drug’s modest benefit is worth its safety risks. Japanese pharmaceutical company Eisai, which developed the drug, has denied that lecanemab played a part in one death, and has yet to determine if it was involved in the other. “It’s quite a complicated balancing act for risks and benefits,” says dementia specialist Rob Howard.

Nature | 6 min read

Reference: The New England Journal of Medicine paper

A path out of China’s zero-COVID policy

China is showing signs of easing its strict zero-COVID policy after an unusual outbreak of protests against strict lockdowns, mass testing, quarantining and travel restrictions. But loosening health protections carries the risk of a wave of deaths and severe disease. To minimize these, researchers recommend that China ramp up vaccination rates, stockpile antiviral drugs and focus on policies that free medical resources to treat the sickest people.

Nature | 5 min read

San Francisco considers deadly robots

The city of San Francisco, California, is considering allowing its police force to use robots to kill people. Deadly robots have been used in the United States before, but a new state law that requires the police to seek government approval to use military-style equipment has thrust discussion of them into the open. Proponents argue that killer robots offer an option of last resort to protect people from a mass shooter or terrorist. Critics say the technology could normalize remote killings by police and exacerbate racial disparities that were so powerfully publicized by the Black Lives Matter movement.

The New York Times | 6 min read & Wired | 8 min read

Pupating ants make milk for baby ants

During their pupal stage, between larva and adult, ants are immobile and were previously thought to be pretty much useless to the rest of the colony. Now researchers have discovered that they have a pivotal role, secreting a nutritious fluid that is drunk by adult ants and fed to larvae. Analogous to mammalian milk, the secretion seems to be essential for young larvae to grow strong and healthy. The pupae also receive parental care: if the secretion is not removed, it can hurt them. “It is really surprising that nobody else noticed this before,” says ethologist Patrizia d’Ettorre.

Nature | 4 min read

Go deeper with an expert analysis by ethologist Patrizia d’Ettorre and myrmecologist Kazuki Tsuji in the Nature News & Views article (6 min read, Nature paywall)

Reference: Nature paper

Features & opinion

In praise of basic biology research

A Nature editorial implores science policymakers and funders to resist the temptation to push for quick returns on research in fundamental biology. The path from basic science to fruitful applications resembles “a drawing of a maze, with plenty of circles, U-turns and dead ends”, says the editorial. But there’s no doubt that such research does have an impact if it is allowed to thrive.

Nature | 5 min read

Quote of the day

“How do you explain why that’s powerful? It just is. People had nothing. Their families were erased. And now we can bring them back a little bit.”

Genealogist Jennifer Mendelsohn is involved in a project offering DNA testing kits for free to help Holocaust survivors and their children to find family connections. (Associated Press | 4 min read)