A few years ago, I started looking at the underside of logs and it changed my life. I found a secret carnival of the most bodacious and interesting organisms I had ever seen. Bubbles of candy-pink gloss on stilts (Comatricha nigra), bunches of rainbow iridescence on toffee strings (Badhamia utricularis), bouffants of raspberry parfait (Arcyria denudata) – and those are just a few that have appeared on bits of wood in our urban garden.

Slime moulds, or myxomycetes, spend part of their life cycle as what are known as fruiting bodies – which look a bit like tiny mushrooms, hence why they were once classified as fungi (they’re actually in the kingdom Protista). Often you will find them, at this stage, in a colony – or, well, I’d suggest galaxy, sweetshop or funfair would be more accurate for a collective noun.

Their bonkers beauty was the gateway for me. The first time I saw one was an astonishing image by the photographer Barry Webb published in New Scientist. I stared at it for ages because I couldn’t work out what it was or why I’d never heard about something so ridiculously beautiful. It looked like an elongated crimson spog – you know, the bobbly ones in liquorice allsorts no one likes – balanced on the longest eyelashes in the world. Webb had found this Stemonitis in a woodland in southern England. Up the road from me! I was hooked.

It didn’t take long to get my eye in. With a 40x magnification jeweller’s loupe (a 10x one is fine,........

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