A worm’s-eye view

ARCHAEOLOGICAL evidence suggests that worms have been around for 600 million years, but Japanese religious lore offers a charming alternative. Certain of the Shinto gods decided to create the world’s creatures from living clay; formulating, in turn, animals, birds, fish and insects. At each stage their creations asked: ‘What shall we eat?’ When they created Man, he was told to eat everything. Then, the gods noticed some small clay scraps that had been dropped and decided to create worms, which they instructed to live underground and eat soil—although they could come to the surface from time to time in search of anything they found edible.

What worms eat may have engaged a few good minds over the centuries,. This was his last work, published in 1881, six months before his death, and probably his least remembered. However, it reviewed and sold well and, in this age of intensive farming with its soil-compacting machinery, chemical pesticides, fertiliser concentrates and over-cropping—everything that is unfriendly to one of Nature’s friendliest creations —Darwin’s message appears potently relevant. He estimated that an acre of mid-19th-century arable land, the result of centuries of gentle pummelling and fertilisation by farm animals and traditional toil by countrymen, contained 53,000 earthworms. He further calculated that, over the course of a year, they moved 15 tons of soil to the surface—a process known to agrology as bioturbation.