My youngest son is at the wheel. We're bumping along the cracked runways of a disused airfield. It's a sparse and grainy landscape, a scenario from a video game. Two or three other cars scuttle like bugs under the blind scrutiny of the derelict control tower. RAF Davidstow aerodrome is pitched, implausibly, at the northern edge of Bodmin moor. It was built in 1942 and closed three years later. They hadn't bargained for the weather. In the 1950s it became a motor racing circuit and once hosted a Formula 1 race. But Cornwall isn't Monaco. If it wasn't the mist, it was the rain and the Atlantic gales. At the first meeting it was sheep down the back straight. Where Wellington bombers once hauled themselves into blank skies and dashing racers hurled their Connaughts and Cooper-Bristols through storm-blown chequered flags, we clatter the potholes in my wife's Clio. But it's a beautiful day.
I have mixed feelings about my son learning to drive. It feels wholesome and fatherly to be teaching him a practical skill, but my fear is that if he's anything like I was at the age of 17 he won't be fit to be on the road. I was a confident young man with well co-ordinated perceptual and motor skills, good reflexes and a sound knowledge of the highway code. What I lacked, as 17 year olds do, was a fully connected frontal lobe. Brain structure is not fixed at birth but follows phases of growth and pruning. Nature and nurture converge to modulate the size of brain cell populations and the integrity of their connections. It starts in the womb and continues through infancy, into adolescence and beyond with different areas of the brain developing at different rates. The frontal lobes, whose function, among other things, is to inhibit risky behaviour, are the last regions to mature. They do not reach full bloom until around the age of 25. Given that their frontal lobes are still under construction, it is perhaps not surprising that teenage drivers account for a disproportionate number of serious road traffic accidents. Research in the US shows that not only are teenagers four times more likely than older drivers to be involved in an accident, and three times more likely to die in one, but that the presence of other teenagers in the vehicle significantly increases the likelihood of a crash. The risk is doubled with two passengers and quadrupled with three or more. This fits with experimental studies showing that young people consistently take greater risks when their friends are watching. So why should I encourage my son to drive? We live in a rural area with wretched public transport services. You need a car to have a social life and, quite simply, I know him and trust him better than I do his friends.
Later, my wife and I drive out to a pub for Sunday lunch. We order drinks in the bar and are shown to our table. It's next to a woman who is eating alone. She has almost finished her meal. After my beer, I have a glass of red wine. The woman at the next table leaves. The bottle of Shiraz she's been drinking is four fifths empty. I wonder if she's driving. Our food is good but was a little slow to arrive and I regret not ordering a second glass of wine. The waiters seem to be keeping a low profile. I don't want to interrupt my meal with another visit to the bar, so I glance sideways. Should I…? I do. I reach over and help myself to the bottle on the adjacent table. My wife is mortified. "You can't do that," she says. "It's paid for," I point out. "Not by you," she says. An older couple who've been sitting vacuum-packed in silence look on with disapproval. "They're talking about you," my wife says, and I tell her I'm glad they're having a conversation. But I suppose she's right. I've only had a couple of drinks and my frontal lobes are already recalibrated for recklessness.
I've bought my son a camera for his 17th birthday. His formal driving lessons start next week but he's eager to get on the road. Now. I choose a quiet stretch out on the moor. We're both apprehensive and he stalls a couple of times, but then we're away. It's exhilarating. He even pulls out an emergency stop for a cow and we park to get a picture of the animal. The next day I'm heading north on the M5. My son sits beside me, plugged into his iPod. Around Bristol, driving through sunshine and rain, we are suddenly enveloped in scintillating sprays of colour. There is a glorious rainbow up ahead, the most brilliant I have ever seen, and now it seems to have absorbed us. In a flash it reverts to its position in the sky and then swings down again as we hurtle through another galaxy of water droplets. Then we roll to a stop. We scarcely move for the next hour and a half. Dusk descends; blue lights and sirens shatter the peace. I picture brutal death a mile up the road but here people are listening to their radios or stepping out for a stretch and a smoke. I catch up with the sports pages. When at last we drive on past the remaining wreckage of the accident, over the sanded stains, I think of the victims and wonder if they saw the rainbow. Perhaps it was the last thing they saw.
