The average American walks less than 400 yards a day, preferring the car to Shank's pony. Are the British heading the same way?

IF DARWIN is right, in a couple of generations Americans should begin to lose the use of their left legs. Later, the leg will probably disappear altogether. The right leg will stay, but will be modified, better to suit its main use - to push the accelerator and brake pedals of automatic vehicles.

The evolutionary change will happen because, as Americans stop walking, the use of both legs should become redundant. Instead - even more than now - they will drive everywhere.

I've just come back from two weeks in America. I met one Californian who admitted he drove 800 yards to work every day "because it's easier and there are no sidewalks". Another confided that her children's daily school run involved a drive of no more than 400 yards each way.

One PhD student at Stanford (Chelsea Clinton's university) told me that a recent survey showed that the average American now walked less than 400 yards a day, and that almost every journey, no matter how short, involved the use of a car. Pedestrians, common and widespread in Europe, are now an endangered species in the States (every bit as rare as the peregrine falcon and the Californian condor) as their natural habitat (the footpath) is being slowly destroyed.

I can personally vouch for this. I asked a hotel receptionist where the nearest drugstore was and she gave me instructions that clearly involved driving. When I told her I was walking, she looked at me as though I'd just told her that I was travelling by spaceship. "You're walking!" Brief silence. "I think it's too far to walk." It was less than 1,000 yards away.

But the distance wasn't the problem. Initially, the lack of footpaths were. The grass verges no doubt gave the passing motorists nice views, but they did little to aid the journey of those who prefer DIY transport. Eventually I reached a busy dual carriageway. I had to walk on the hard shoulder in order to reach the shopping mall. Motorists tooted me as though I was some sort of lunatic, and one or two of them took exaggerated avoiding action. I have done many hikes, over difficult terrain, but I swear that those few hundred yards, on the dual carriageway's hard shoulder, were the most hazardous of my life.

Or at least it was until a new, sterner challenge faced me. I now had to cross the road. There was no footbridge, no traffic lights, merely two carriageways of traffic doing 55mph in opposite directions separated by a crash barrier. When the coast was clear, I dashed, vaulting the barrier, only to be faced by another hazard. A giant open drain now separated me from the shops like a (fortunately empty) moat, no doubt designed to keep foot-powered subversives out. By the time I reached the drugstore I felt in need of far more than a packet of hay-fever tablets. I would have been more relaxed if I'd spent days trekking through a wood full of grizzly bears.

Nothing is being done to try to quell the "four wheels good, two legs bad" American Way. Gasoline prices still hover around the dollar a gallon mark (in some states, they're actually nearer 80 cents a gallon, making petrol about a quarter the price of bottled water). Out-of-town shopping malls are now the normal way to shop. Vehicles are getting bigger and thirstier. Even in liberal San Francisco, there seemed little support for raising the price of gasoline.

Of course, with Britain's hideous new out-of-town stores and our reliance on cars for commuting and the school run, we are heading in the same direction. And with John Gummer and John Prescott as the leading spokesmen for common sense, the case against these Americanisms does not look good. Yet I have faith in the good sense of the British. Besides, I am rather fond of my left leg.