A million years ago, “beavers the size of bears roamed North America”, says Leila Philip in LitHub. The “deep weirdness” of their modern descendants poses an evolutionary puzzle. Swimming, they seem more like seals than big rodents, but then their “dexterous forepaws” look startlingly human with “five nimble fingers and naked palms”. They groom their lustrous fur with “catlike fastidiousness”, standing on “gooselike hind feet”, each as wide as the beaver’s head. Then there’s the “reptilian tail”, which looks like it’s been “run over by a tractor tire, the treads leaving a pattern of indentations that resemble scales”.

May 14, 1796 was a “golden day in the history of science”, says Derek Thompson in The Atlantic, “but a terrifying one for a certain eight-year-old boy”. Determined to prove that humans could be inoculated against smallpox by infecting them with cowpox, the British physician Edward Jenner slashed the arm of his gardener’s “brave and healthy son”, with a knife dipped in the ooze from a cowpox blister. After the boy recovered from a brief chill, Jenner stabbed him with a lancet infected with smallpox. “Nothing happened.” Jenner had invented a cure for “one of the deadliest viruses in world history”. The name he gave to this revolutionary new treatment, from the Latin for cow, was: “vaccine”.

Joe Biden’s clean energy bill was rightly trumpeted when it was passed in August, says Edward Luce in the FT. But it looks like many of its green projects will never materialise – and Democrats only have themselves to blame. Last week, an accompanying bill that would have cut through the “Kafkaesque” red tape blocking new solar plants, wind farms and so on was torpedoed by lawmakers. Republicans opposed it for the usual reason: it had the name “Biden” on it. But they were joined by lefty Democrats like Bernie Sanders, because the bill would have enabled a new gas pipeline in West Virginia. It will now be “all but impossible” for Biden to hit his target of cutting 50% of US emissions by the end of the decade.

“Why should a country at war waste time bothering about opera?” says Gerald Malone in Engelsberg Ideas. Because it’s a struggle to “assert its national identity, that’s why”. Within days of the Russian invasion, Vasil Vokun, director of Lviv Opera House, decided his venue was “a dog in this fight”. Unperturbed by air strikes, he has continued to stage performances as usual, albeit with a few adjustments – the audience is limited to 300 people, as that’s the capacity of the “hastily constructed” underground air-raid shelter. “London’s West End grit in the Second World War Blitz springs to mind.”