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Cows stand in a pen near Fort Stockton, Texas.

Beef farming drives deforestation and is a major source of methane emissions.Credit: Bill Clark/CQ-Roll Call, Inc via Getty

Meat-free Monday could halve deforestation

Replacing just one-fifth of global beef consumption with a meat substitute within the next 30 years could halve deforestation and the carbon emissions associated with it. Researchers modelled the effects of swapping beef with a fungus-based meat substitute called mycoprotein — familiar to many as Quorn. Replacing 80% of beef with mycoprotein would eliminate about 90% of forest loss. “It should not be seen as a silver bullet,” says sustainability scientist and co-author Florian Humpenöder — but it could be a part of the solution.

Nature | 4 min read

Reference: Nature paper

Meat substitution: Line chart showing future environmental effects of replacing beef consumption with microbial protein.

Source: Ref. 1

Pig-heart transplant was infected with virus

In January, a person in the United States became the first recipient of a pig-heart transplant. He died two months later, and transplant specialists now say the genetically edited pig heart he received carried a porcine virus that could have contributed to his death. Xenotransplantation critics have expressed concerns that the procedures could transfer animal viruses to humans, but the virus in this case — porcine cytomegalovirus — is not known to be able to infect human cells. The main concern is that the virus can damage the heart.

MIT Technology Review | 9 min read

Read more: What we can learn from the first pig-to-human heart transplant (Nature | 7 min read, from January)

Graphics show COVID’s unfathomable toll

The World Health Organization (WHO) estimates that the COVID-19 pandemic has caused the deaths of nearly 15 million people (other key estimates indicate that number could be closer to 18 million). “It's a staggering number and it's important for us to honour the lives that are lost, and we have to hold policymakers accountable,” says WHO assistant director-general Samira Asma. The BBC illuminates the inconceivable with graphics that show which countries seem to be vastly underreporting deaths and how different regions compare — some countries with zero-COVID strategies, such as Australia and Japan, actually saw fewer deaths than would normally be expected.

BBC | 4 min read

Read more: COVID’s true death toll: much higher than official records (Nature | 5 min read, from March)

Features & opinion

Climate simulations have a ‘hot model’ problem

The sixth and latest Intergovernmental Panel on Climate Change assessment weights climate models according to how well they reproduce other evidence. Now the rest of the community should do the same, argue five climate modellers and analysts. No computer model can simulate every aspect of our planet’s system of interconnected oceans, land, ice and atmosphere exactly. The authors call for a ‘model meritocracy’ that prioritizes, where appropriate, results from models known to have more realistic warming rates. Understanding that some predictions are ‘too hot’ does not invalidate the usefulness of modelling, climate scientist and co-author Kate Marvel told Science — just that limitations must be taken into account. “They’re not crystal balls.”

Nature | 10 min read & Science | 6 min read

Climate models:Choice matters. Line graph showing four climate scenarios and the difference between models.

Source: Z. Hausfather et al.

Australia must reinstate funding independence

Australia must abolish a law that allows politicians to veto research grants, argues a Nature editorial. It calls on leaders to heed the Australian National University’s vice-chancellor, the astrophysicist and Nobel laureate Brian Schmidt, who called the power of veto and political interference “an existential threat to Australian universities”, which “can corrupt knowledge and slow down its creation”.

Nature | 5 min read

QUOTE OF THE DAY

“It’s literally slower than watching Australia drift north, and people log in live on the Internet to watch it.”

Author and pitch-drop fan Nick Earls ponders the attraction of the longest running laboratory experiment in the world: a funnel of goo dripping into a beaker that has been going since 1927. (The Guardian | 7 min read)