Country diary: webs of intrigue in a shadowy cave

The entrance to the cave is a low slot, 3 metres up the former quarry face. To reach it, we climb rock smoothed by many hands and feet. Inside, the muddy floor is similarly worn, dished and dimpled.

My son moves easily, but I’m on all fours from the off. When I see the roof is decked with small globes of silk I crawl lower still, to avoid dislodging any. They are the nursery webs of cave spiders, Meta menardi, each hanging from a mere half-dozen threads. I comment on their delicacy, but the boy assures me that a rope of spider silk can support the weight of a jumbo jet.

The ceiling glitters in torchlight as we go deeper – each gleam is a bead of condensation. In wetter parts, water drips from nipples of calcite. The butterscotch-coloured flowstone on the walls has been buffed ivory here and there by the passage of bodies.

It was beneath a layer of this deposit, now dated to 121,000 years old, that the 19th-century geologist William Buckland catalogued the bones of hippos, bison, deer, rhinoceroses, elephants and hyenas. This ancient ossuary is now held by the Yorkshire Museum, but fossil poop in among the bones identifies the hyenas as the original curators.

The feeding remains here now are smaller: scatterings of moth wings, several in the black-banded mustard livery of large yellow underwings. These must have been dropped by bats feeding last autumn. We can thank lockdown for them not having been swept away by other feet and knees. Around the point where daylight no longer shows, we finally find the web-makers.

Their ebony legs are needle-thin and the females have red-gold abdomens with swirling patterns like those on the surface of Mars. Some are suspended on threads; these ones pirouette in the disturbance of our heat, breath and LEDs. Others step along the walls, toe to toe with their shadows – a precisely choreographed dance in which the projected partners billow and swell to gothic proportions in the lurching torchlight.

Crawling out again, we meet the first of the babies – tiny, newly hatched and making their way resolutely towards the light, where they will wait for an auspicious breeze, then spin a long thread to lift them up and out, into the bright unknown.

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