NATURE COLUMN: Bill Cawley

LOLA the cat unwittingly gave me the theme for this week’s nature notes some time ago.

As a Victorian novelist famously wrote: ‘it was a dark and stormy night’ – I looked up and on the window sill begging to be let in was the cat and as an offering to ensure this outcome, dangling from her jaw was a writhing earthworm.

The earthworm was the subject of a scientist with a strong North Staffordshire connection – the grandson of potter Josiah Wedgwood – Charles Darwin.

His last book published the year before his death in 1882 and snappily entitled The Formation of Vegetable Mould through the Action of Worms with Observations on their Habits is the consummation of a lifetime of thinking on the impact of small changes over immense periods of time which lies at the heart of his theory of evolution.

Worms are both humble and interesting, as he attempted to prove, and a worm’s work, when summed over all worms and long periods of time, can shape our landscape and form our soils on which the whole of nature depends.

He made two claims for the earthworm. First, in shaping the land, their effects are directional.

They grind rock into smaller particles as it passes through their gut loosening the soil as they churn it.

Secondly in forming and agitating the soil, they maintain a steady state amid constant change.

Darwin set out to prove that worms form the soil’s upper layer, the so called vegetable mould, by bringing earth to the surface and depositing it there in the form of castings

“I was led to conclude that all vegetable mould over the whole country has passed many times through the intestinal canals of worms,” he said.

The great scientist’s book is a labour of love delivered in cherished painstaking detail.

He spends hundreds of pages describing experiments on collecting and weighing castings and the decomposition of mould.

All great science is a happy marriage between generality and the exact, excitement and elucidation.

Darwin and his beloved worms, as it were, left no stone unturned in this final proof of evolutionary theory.

Earthworms play an important role in breaking down dead organic matter in a process known as decomposition.

This is what the earthworms living in your compost bin are doing and earthworms living in soils also decompose organic matter. Decomposition releases nutrients locked up in dead plants and animals and makes them available for use by living plants. Earthworms do this by eating organic matter and breaking it down into smaller pieces allowing bacteria and fungi to feed on it and release the nutrients.

Darwin died a year after his book was published on April 19, 1882.

He wished to be buried in the soil of his village in Kent, a final and earthly gift to his treasured worms.

Sadly the wish was denied and he lies in a sealed brick vault underneath the floor of Westminster Abbey.