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Atacama Cosmology Telescope in the Atacama Desert in the north of Chile.

Data from the Atacama Cosmology Telescope suggest the existence of two types of dark energy at the very start of the Universe.Credit: Giulio Ercolani/Alamy

Hints of a new type of dark energy

A previously unknown, primordial form of dark energy could explain why the cosmos now seems to be expanding faster than theory predicts. This second type of dark energy — the ubiquitous but enigmatic substance that is pushing the current expansion of the Universe to accelerate — might have existed in the first 300,000 years after the Big Bang. If the findings are confirmed, they could help to solve a long-standing conundrum surrounding data about the early Universe, which seem to be incompatible with today’s measured rate of cosmic expansion.

Nature | 5 min read

Reference: arXiv preprint 1 & arXiv preprint 2

COVID-vaccine booster shot shows promise

Data from Israel suggest that a third dose of a COVID-19 vaccine provides some extra protection from infection. Researchers evaluated 1.1 million people over the age of 60 who had received their first two doses at least five months earlier. Twelve or more days after receiving a third jab, participants were about 19.5 times less likely to have severe COVID-19 than were those in a similar group who had received only two jabs. The results reflect the limitations of observational studies and don’t speak to the ethics of giving some people in rich countries boosters when billions of others are still waiting for their first jab.

Nature | 4 min read

Coronaviruses might spill over all the time

Severe acute respiratory syndrome (SARS)-related coronaviruses could jump from animals to people an average 400,000 times per year in undetected spillovers. Researchers based their estimate on information about where people live in southeast Asia, small seroprevalence surveys that tested people for antibodies against SARS-related coronaviruses, and maps of the habitats of 23 bat species known to harbour these coronaviruses. They found that close to 500 million people live near the bat species, with the highest risk in southern China, Vietnam, Cambodia and islands of Indonesia. There are many caveats, and the research is still preliminary, but scientists say it highlights how little we know about the extent of zoonotic spillovers.

Science | 5 min read

Reference: medRxiv preprint

Features & opinion

How HBCUs nurture Black scientists

Historically Black colleges and universities (HBCUs) in the United States are experiencing a record surge in enrollment for the 2021 academic year. However, many HBCUs have struggled to secure the same financial resources as predominantly white institutions, such as endowments and federal and state funding. Five scholars who work at or attended an HBCU discuss why the institutions are key to increasing the Black workforce in science, technology, engineering and mathematics.

Nature | 14 min read

Futures: science fiction from Nature

In this week’s helping of short stories for Nature’s Futures series:

• A migraine sufferer learns a hard truth about her relationship after giving her partner a glimpse of what she really feels in Shared pain.

• An exasperated spaceship captain tries to tackle fake news (and the lure of tentacline mould-brain) in Emergency housekeeping rules for the SS Heart of the Sun

When wild animals take to the streets

From the alleyways of Aspen, Colorado, where epicurean bears forage among restaurant dustbins, to “leopard-terrorized hamlets” in the Himalayas, author Mary Roach investigates how wild creatures clash with humans. Fundamentally, she asks: when we encroach on the habitat of wild creatures, is it any surprise that they advance on ours?

Nature | 5 min read

Podcast: blue food to help feed the world

Nature editor-in-chief Magdalena Skipper speaks to Ismahane Elouafi, chief scientist at the Food and Agriculture Organization of the United Nations, about how aquatic foods could help to feed the world's population in a healthy, sustainable and equitable way. When it comes to feeding humanity with healthy, sustainable food, “We know very well that we are losing ground,” says Elouafi. “We have 811 million who are facing hunger.... that’s where blue foods are very important.”

Nature Podcast | 22 min listenSubscribe to the Nature Podcast on Apple Podcasts, Google Podcasts or Spotify.

Quote of the day

“He’d come up with an idea and say, ‘There’s no point in asking if someone wants it, because they can’t imagine it.’”

Belinda Sinclair remembers her husband, computing pioneer Clive Sinclair, who has died aged 81. His inventions included groundbreaking pocket calculators, an early electric vehicle, and the legendary ZX Spectrum home computer — although Sinclair himself preferred to use a slide rule. (The Guardian | 5 min read)