INSIGNIFICANT events in childhood can have seismic effects on the direction of one’s life.

There was a classic example on Radio 4 this week.

Prof John Lawton is one of the founding fathers of the Ecotron, a system of controlled biological ‘worlds’ that enable scientists to study environmental changes in miniature.

Interviewed on Radio 4’s The Life Scientific by Jim Al-Khalili, Prof Lawton confessed that after a holiday at Lytham St Annes he was handed by his parents a ‘good behaviour’ prize of an Observer’s book of British Birds.

It was this unassuming little book that set him on a course that was to determine his entire life in the ecological sciences.

He said he devoured every word of the book and used it so much he had to buy a new one after three years.

“The first one simply fell apart,” he said.

The same can’t be said for me, but I have that very book – and most likely that very edition since Prof Lawton and I are of an age.

Like the professor, I absorbed the contents of the Observer book and by the time I was seven knew far more about British avian species than could be described as healthy.

Songs, eggs, nest types, colouration, habitat, flight and migration patterns – I knew it all and could bore for Britain on it.

Fortunately for the science of ecology, another booklet stepped into my path and waylaid me.

It was the I-Spy series.

These booklets were incredibly popular in the 1950s and 1960s but seemed to skip a generation.

I’m told they were still around in the 1970s and 1980s, but I never saw them. My own children could not savour the delights of I-Spy.

But my grandchildren will. I-Spy book are back with a vengeance.

Sonia Benster from Lindley Children’s Bookshop says they’re flying off the shelves.

I love it when bookshop owners say that. I’m tempted to sit by the shelves and wait for the magic to happen.

Whee! There goes another one! Look at the wings on that!

It was through I-Spy that I learned that since 1840 and the introduction of the Penny Post, post boxes are required by law to carry the name of the sovereign in whose reign the box was installed.

There are still a number of boxes with the legend VR (Victoria Regina, 20 points), many more with G VI R and thousands with ER on the side (5 points).

The I-Spy principle is simple – and its simplicity is the source of its success now revisited.

Each I-spy booklet is themed – cars, butterflies, street furniture (the one with postboxes in it), wildflowers, creepy-crawlies, flags, public transport, birds and so on.

There’s a picture of the object you must look out for and a dateline and a box to tick when you see one.

You get five points for a common object and 20 or more for a rare one.

When you’ve ticked all your boxes you can send off for a certificate of merit and a badge.

It’s really quite heart-warming that children brought up on TV and video games and allegedly with the attention-span of a tadpole (I-Spy Pondlife) can find time for this kind of activity.

It’s even more heart-warming that another generation of parents is recognising the I-Spy concept as intellectually challenging.

Those of my generation will remember that the original books had a Big Chief I-Spy (retired headmaster Charles Warrell, initially) and there was a lot of talk about Hawkeye his assistant, Redskins, wigwams and feathers.

As the bleak sun of political correctness rose, all this stuff was deemed offensive to native Americans and was quietly dropped.

The old books were quite tatty and fragile but the new ones are plush and shiny. The old ones had rather dull illustrations while the new ones have clear photographs.

Prof Lawton and I are probably deteriorating with age. But the I-Spy tradition marches forth into a glorious and glossy new future.