Beyond the answers - interesting background to this quiz

The children's book that became a Hollywood favourite

Erich Kästner published Lisa and Lottie in 1949, a story about twin girls separated as babies who meet at summer camp and swap places to reunite their parents. The German author had already made his name with Emil and the Detectives, and his books were among those burned by the Nazis in 1933. The twin-swap plot later inspired the much-loved American film The Parent Trap, which in turn introduced the story to generations who never knew its German origins.

When phosphorus glowed in the dark

Phosphorus takes its name from the Greek for "light-bearer", because white phosphorus glows faintly when exposed to air - a phenomenon called chemiluminescence. Discovered by the Hamburg alchemist Hennig Brand in 1669 while he was searching for a way to make gold from urine, it became the first element isolated by a named individual. Its symbol, P, is one of the simplest in the periodic table.

A film that asked what it means to be human

Stanley Kubrick's 2001: A Space Odyssey, released in 1968, follows a mysterious black monolith across human history and ends with one of cinema's most debated sequences. Kubrick co-wrote the screenplay with science-fiction author Arthur C. Clarke, and the film is remembered for its minimal dialogue, classical score and the homicidal computer HAL 9000. Its influence on later science fiction, from Blade Runner to Interstellar, is hard to overstate.

Spain's quiet lead in protected landscapes

UNESCO's Man and the Biosphere programme recognises reserves that combine conservation with sustainable human use, and Spain holds more of them than any other country. Its reserves range from the high mountains of the Pyrenees to the wetlands of Doñana, and many are inhabited working landscapes rather than strict wilderness. The programme's aim is to show that people and nature can coexist, not just in theory but in day-to-day land management.