“I suppose it’s quite a lot of spiders…” Alistair McGregor says casually, rotating his hand to catch a plump, leggy female who is making a bid for freedom. “We can never have too many though – they eat each other.”

We’re standing in the spider room at his lab in Oxford, home to 10,000 American house spiders and a menagerie of other disturbing animals, from centipedes to tarantulas. The air is deliberately musty, to emulate the dark corners they like to lurk in, and the walls are laden with shelves upholding row upon row of glass jars, tanks and petri dishes.

“Sometimes the crickets escape and we can hear them singing in the corridor,” McGregor chuckles – then quickly follows that they’ve never had a spider on the loose. (His students later tell me that this happens regularly.)

The room is fronted by an appropriately heavy-duty door, like the hatch of a submarine. Being old, sometimes it gets stuck and his students then get trapped inside.