Rats could become man's best friend

Guided rats, controlled through implants in their brains, could one day be used to search for buried victims of earthquakes, scientists said today.

The "rodent rescue" idea follows an extraordinary experiment in which researchers steered five rats through an obstacle course by remote control.

Writing in the journal Nature, the scientists said "ratbots" could be deployed on rescue missions.

The researchers, led by Dr Sanjiv Talwar at the State University of New York, implanted electrodes into areas of the rat brain responsible for sensing a reward, and those which process signals from their whiskers.

Commands and rewards were transmitted by radio from a laptop computer to a backpack receiver strapped to each rat, making them run, turn, jump and climb where the scientists wanted from distances of up to 500 metres away.

The rat could carry an infra-red sensor to detect body warmth and a locater system such as GPS. It was even possible that, when the smell of a human triggered a particular electrical pattern in the rat's brain, another implant could signal to rescuers a victim had been found.

Dr Talwar acknowledged there might be strong ethical objections to such ideas but said: "Our animals were completely happy and treated well and in no sense was there any cruelty involved. Nonetheless, the idea is sort of creepy. I don't know what the answer is to that."