Pigeons just can't resist a flutter on a fruit machine

Pigeons feel the urge to gamble just like humans, scientists claim.

In experiments, birds given the chance to play a pigeon "fruit machine" could not resist the lure of the jackpot - even when the odds were stacked against them.

The birds were trained to peck on either of two keys that displayed projected vertical or horizontal lines as well as red, yellow, green and blue colours.

Pecking keys produced rewards of food pellets, which varied according to the displays. The "jackpot" of ten pellets was delivered only after a key was pressed that presented a vertical line and a certain "signal" colour, for instance red.

Psychologist Professor Thomas Zentall and Jessica Stagner, from the University of Kentucky, wrote: "Pigeons show a tendency to make maladaptive decisions similar to those of humans.

"That is, pigeons prefer a signal for a low-probability, high-payoff alternative over a signal for a certain low-payoff alternative that on average provides 50 per cent more reinforcement."