14 October,2010 04:27 PM IST | | AFP
Scientists have discovered that pigeons feel the urge to gamble just like humans.
Some gamblers like to forgo money their winnings for the chance of a much bigger win - and a new research by Thomas Zentall and Jessica Stagner from the University of Kentucky shows that pigeons like to take the same risk.
They prefer an all-or-nothing outcome than the guarantee of a much smaller reward, reports ABC Science.
The researchers say this runs contrary to optimal foraging theory, which says animals evolve to make the most rational choices possible to guarantee their survival.
Instead, it seems pigeons behave more like human gamblers, risking everything for the small chance of a big return.
In the experiment, eight pigeons were taught the outcomes of two different sequences if they pecked either a vertical or a horizontal line on a screen.
They learned that if they chose the vertical line, they had a 20pc chance of a big food reward (10 pellets), or an 80pc chance of no reward at all (0 pellets). If they chose the horizontal line, they had a guaranteed reward of three pellets - effectively a non-gambling option.
When the pigeons were then presented with the choice of pecking either vertical or horizontal lines, to the surprise of the researchers, most chose the vertical line despite the fact that it gave them less food overall.
Averaged over many trials, six of the eight pigeons made choices that gave them an average of two food pellets over an alternative three.
"This choice behaviour mimics human monetary gambling in which the infrequent occurrence of a stimulus signalling the winning event is overemphasised and the more frequent occurrence of a stimulus signalling the losing event is underemphasised," the researchers said.
The study appears in Proceedings of the Royal Society B.
