I have an idea for David Attenborough’s next natural history series. Forget Life on Earth – there’s enough material for 12 one-hour episodes of Life in and on My Caravan.

I recently popped up to where it’s stored for a mid-winter check and, in the short period since I’d kissed it sweet dreams for its shutdown, it had become a haven for a wide variety of flora and fauna.

My suspicions were aroused as I neared. I could have sworn I’d seen the curtains twitch and heard the scurrying of tiny feet.

I imagined a scene like that in Toy Story, just before the human’s return, when all manner of things inside scramble to find places to hide. Was that a “ssshhhh!” as I opened the door?

All seemed quiet, until a startled spider the size of a saucer bungee-jumped from one side of the pelmet to the other.

A family of woodlice en route from the draining board to the window ledge had taken an unfortunate diversion via the sink – where their woodland camouflage was, frankly, useless.

And something larger and furrier was halfway through building a nest out of cleaning cloths. It was, quite obviously, a temporarily stalled hive of activity.

Also immediately apparent was the wide-ranging variety of vegetation that had taken hold both outside and inside the van.

From the outside, the few short months of abandonment had resulted in a staggering density and variety of mould and algae. What is it about caravans and green slimy stuff?

Other things I leave open to the elements don’t transform in such a dramatic way. The rabbit hutch is still the same colour it always was. As is the dog.

I need to conduct a scientific test to see if a rectangle of random white metal turns the same colour over the same period. Actually, what’s the point? I know it won’t.

Inside, the carefully co-ordinated, show-house-perfect collection of fabrics and soft furnishings (ahem) had become a rainforest.

There were creepers dangling from the rooflight, amoeba multiplying in the sink, moss covering most work surfaces and giant redwoods sprouting majestically in the corners.

OK, I lied about the last bit, but an unfeasible amount of plant life had germinated in a fraction of the normal time. I reckon there are sufficient unexplained phenomena to warrant at least a one-hour special.

I’ll have a word with my friends at the BBC, so keep an eye on the TV schedules…

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