Researchers at Oxford University spent 10 years studying homing pigeons using global positioning satellite (GPS) and were stunned to find the birds often do not navigate by taking a bearing from the sun.

Instead, they fly along motorways, turn at junctions and even go around roundabouts, adding miles to their journeys, British newspapers reported on Thursday.

"It really has knocked our research team sideways," Professor Tim Guilford said in the Daily Telegraph. 

"It is striking to see the pigeons fly straight down the A34 Oxford bypass, and then sharply curve off at the traffic lights
before curving off again at the roundabout," he said in The Times.

Guilford said pigeons use their own navigational system when doing long-distance trips or when a bird does a journey for the first time.

But when they have flown a journey more than once they home in on a habitual route home.

"In short it looks like it is mentally easier for a bird to fly down a road... they are just making their journey as simple as possible."