Birdbrains

Dickens imagined a few smoky sparrows twittering in smoky trees at Staple Inn, in Holborn, in the middle of London, and agreeing a pretence: “Let us play at country.” These days, many people at home, with little traffic about, can hear the birds (who get up early at this time of year). Blackbirds are a treat and tits insistent. Since cities are no longer smoky, birds often do better in town than in the country. As we report, scientists have found two avian advantages for city life: a big brain and plenty of chicks. Crows and seagulls have big brains for their size; pigeons raise plenty of offspring in unseen nests among the rooftops. Yet, though Staple Inn survives, chirpy sparrows are rarer. Dickens calls their game of pretence a “refreshing violence to their tiny understandings”. Were they not streetwise enough to survive?