Last spring, coyotes strolled down the streets of San Francisco in broad daylight. Pods of rarely seen pink dolphins cavorted in the waters around Hong Kong. In Tel Aviv, jackals wandered around a city park, a herd of mountain goats took over a town in Wales and porcupines ambled through Rome's ancient ruins. As the canals in Venice turned strangely clear, cormorants started diving for fish, and Canada geese escorted their goslings down the middle of Las Vegas Boulevard, passing empty shops displaying Montblanc pens and Fendi handbags.

Nature was expanding as billions of people were retreating from the Covid-19 pandemic. The change was so swift, so striking that scientists needed a new name for it: the anthropause.