Ratbags? No, rodents have a moral code say scientists

THEY have a reputation for being savage animals – but it seems rats may have a moral code.

The rodents would rather avoid hurting others if given the choice, a study found.

To test if they have empathy like people, researchers taught them to press two levers to produce sugary treats.

When one lever gave an electric shock to a rat they shared a cage with or a stranger, nine out of 24 stopped using it – even if it produced twice as many snacks.

Based on brain scans, experts suspect they react to suffering much like humans, in that they would rather it stopped.

But some doubt remains as it may simply be a case of rats finding their neighbours’ shrieks annoying.

Professor Christian Keysers, of the Netherlands Institute for Neuroscience, said: ‘ Perhaps a rat stops pressing the harmful lever because it doesn’t like to hear another rat squeak – just as we do not like to hear a crying baby on a transatlantic flight. Perhaps they do so because they really feel sorry for their neighbour.

‘We don’t know whether our rats had a selfish or altruistic motivation, but I would argue that we don’t always know the motives behind the good deeds of humans either.’

However, their empathy appeared to run out if the shock lever dispensed three times the number of sugar pellets compared with the other lever.

In that case, rats tended to ignore the squeaks and carry on getting treats.

Experts previously found the same part of the brain, the anterior cingulate cortex, lights up in rats witnessing the pain of another animal as is seen in humans.