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The Muon g-2 ring sits in its detector hall amidst other equipment

The storage-ring magnet used for the g − 2 experiment at Fermilab.Credit: Reidar Hahn/Fermilab

Thrilling muon result shakes up physics

Muons — massive, unstable cousins of the electron — seem to be more magnetic than the standard model of particle physics predicts. If this result holds up, it could ultimately force major changes in theoretical physics and reveal the existence of completely new fundamental particles. The Muon g – 2 experiment upheld sensational findings, first announced in 2001, that showed the muon’s magnetic moment — a measure of the magnetic field it generates — is slightly larger than theory had predicted. The results are “extremely encouraging” for those hoping to discover other particles, says physicist Susan Gardner.

Nature | 6 min read

Flummoxed? Physics magazine explains it in cartoon form.

Reference: Physical Review Letters paper

Oldest Homo sapiens DNA tells human story

Scientists have sequenced the oldest Homo sapiens DNA on record, which showed that many of Europe’s first humans had Neanderthals in their family trees. All present-day people whose ancestry isn’t solely African carry Neanderthal DNA, but there are questions about when and how the genetic mixing occurred. Three individuals found in Bacho Kiro Cave in Bulgaria, dated to between 45,900 and 42,600 years old, had “huge chunks” of Neanderthal DNA and probably had Neanderthal ancestors as recently as the past six or seven generations. A woman found in the Zlatý kůň cave in the Czech Republic is thought to be well over 45,000 years old and has Neanderthal ancestry going back considerably longer: 70–80 generations. None of the individuals are related to later Europeans, but the Bacho Kiro people shared a connection with contemporary East Asians and Native Americans. The research adds to growing evidence that modern humans mixed regularly with Neanderthals and other extinct relatives.

Nature | 5 min read

Reference: Nature paper & Nature Ecology & Evolution paper

The skull of a modern human female individual from Zlatý kůň

The skull of a modern human female individual from Zlatý kůň.Credit: Marek Jantač

Big plans for National Science Foundation

The US National Science Foundation (NSF) looks set to receive a US$100-billion boost as part of a $2.3-trillion proposal to revitalize the United States’s ageing infrastructure. Lawmakers plan to introduce a technology directorate, including an agency to commercialize promising climate-related technologies. If the plan comes to pass, it will be a significant expansion for the nation’s second-largest research-funding agency, which currently has an $8.5-billion budget.

Science | 8 min read

Long-awaited hope for meth addiction

Two treatments are showing promise for treating addiction to one of the most hard-to-quit drugs: methamphetamine. In one, researchers combined an opioid blocker with an antidepressant to help quash cravings and raise dopamine levels in the brains of people addicted to meth. In a trial of 403 heavy users, 13.6% of people on the regimen stayed mostly meth-free over 6 weeks, compared with 2.5% of people given a placebo. The other is a psychosocial intervention called contingency management, which reinforces abstinence with prizes. It is showing promise in the US Department of Veterans Affairs health system.

Scientific American | 5 min read

COVID-19 coronavirus update

What’s holding back US virus tracking

Researchers fear that the United States is failing to ramp up genetic sequencing of SARS-CoV-2 fast enough to stay on top of dangerous variants. Laboratories supported by the US government have doubled the rate at which they are sequencing SARS-CoV-2 genomes over the past two months. Still, the country is falling behind others — despite having an enormous capacity to do more. “We have enough sequencers to sequence SARS-CoV-2 from every case, 100 times over,” says immunologist Kristian Andersen. But work is being held back by the fragmented US health system, financial limitations and a lack of coordination between testing labs and sequencing labs.

Nature | 7 min read

Features & opinion

Regulate AI that interprets human emotions

During the pandemic, technology companies have been pitching their emotion-recognition software for remotely monitoring workers and even children, writes Kate Crawford, who studies the social implications of artificial intelligence (AI). But there is deep scientific disagreement about whether AI can detect emotions. Digging into the evidence, Crawford argues that these technologies are reminiscent of discredited ‘lie detector’ tests and should be regulated to protect those who might fall foul of unwarranted uses.

Nature | 5 min read

The trouble with Seaspiracy

Protecting the oceans is not as simple as the hit Netflix documentary Seaspiracy would have you believe, argues marine ecologist and writer Josh Silberg. The documentary’s conclusion that ending global seafood consumption is the best way to protect the oceans lacks nuance and ignores the importance of fishing in many communities around the world, writes Silberg.

Hakai | 4 min read

Quote of the day

“Please have some DNA, please have some DNA.”

Geneticist Mateja Hajdinjak describes the electrifying experience of sequencing remains found in Bacho Kiro Cave in Bulgaria, which yielded the oldest known Homo sapiens DNA. (Nature Ecology & Evolution Community blog | 7 min read)