Ground force

On a mild, wet, early morning last autumn, I came across two earthworms (Lumbricus terrestris) mating on the lawn. At the vibration of my tread, they split apart and, though I try not to anthropomorphise animals (I could never have gone fox hunting if I had), such behaviour did look shifty, as if I had surprised a teenage couple entwined on the family sofa.

I had never before in my life seen such a coupling, which is remarkable considering how many early mornings I have spent in gardens and how common earthworms are, but it underlines the fact that their lives are mostly spent hidden from sight underground. Their influence on our lives is usually therefore hugely underestimated — except perhaps by farmers and gardeners.

The pioneering research on earthworms was done, as everyone knows, by Charles Darwin, culminating in the publication in 1881 of The Formation of Vegetable Mould, Through the Action of Worms, with Observations on their Habits.