Fifty-two butterfly species saw populations decline in 2012 compared with 2011, with 13 experiencing their worst year in records dating back to 1976.

BBC: Butterflies suffered in cold and wet 2012, says charity

In London Mr Hirst presides over two large industrial units producing the butterfly-wing pictures and his photo-realist paintings.

ECONOMIST: Damien Hirst

Push a button and the ballerina's tutu becomes the wings of a butterfly that flutter along two arcs of numerals.

WSJ: The Face of Watchmaking's Future at SIHH and GTE

It was another Dutch one-two in the final of the women's 50 metres butterfly with Chantal Groot taking gold and Inge Dekker the silver.

BBC: What do they say about the best laid plans?