At this point a human operator decides whether the unusual behaviour detected is permissible.

ECONOMIST: A thousand ills require a thousand cures

Both require low temperatures and both depend on similar unusual behaviour by the electrons in the materials concerned.

ECONOMIST: The Nobel prizes

Dolphin watchers in west Wales have spotted unusual behaviour as a female repeatedly tossed a newborn calf into the air.

BBC: Dolphin baby given 'ticking off'

"This is very unusual behaviour for a deer, as they are usually very secretive, especially during daylight hours, " Mr Iley said.

BBC: Deer injures woman in Chelmsford High Street

Once detained, Mr Gill-Webb's behaviour was described as "somewhat unusual" and no ticket was found on him.

BBC: Olympic 100m bottle throw: Man 'wanted Usain Bolt to lose'

The latest search for unknown beasties, carried out by Charles Paxton of the Animal Behaviour Research Group at Oxford University, is rather more unusual.

ECONOMIST: Statistics