Did you ever stop to wonder why geese don't have wheels? The reason that you'll never see an elephant fly is obvious, but how come monkeys never developed wings? Zoologist Matt Wilkinson has some answers, which he'll discuss at a talk about the evolution of movement.
The lecture, on 2 June, is just one of many fascinating evenings in the Royal Institution's summer events programme. Wheeled creatures might be unfeasible, but the planet is crawling with 'ugly' animals that need our help. Simon Watt brings his ugly animal roadshow to the RI on 13 May.
Other highlights include a journey to the centre of the sun (3 May), a primer on gravitational waves (19 May), the future of Martian exploration (16 June), how addiction affects the brain (14 July) and the science of household objects (5 August).
Take a look at the full programme on the RI's website (PDF) for more ideas.
Never visited the Royal Institution before? The Mayfair venue is steeped in history — its researchers (including Michael Faraday and Humphry Davy) discovered 10 chemical elements and claimed 15 Nobel Prizes. The famous lecture theatre is worth the visit alone.
Pedants' note: Although nature never evolved the wheel in animals, examples can be found at the microscopic level.
Image by M@, and not from the Royal Institution.