Reading The Earth Moved I discovered a rich, crowded, underground world, invisible to us who live above ground. This underworld is less accessible than the Marianna Trench - the deepest sea location on earth.
In their underground habitat, earthworms are giants. There are giant earthworms - I've seen them - but in this ecosystem even the smallest worms are giants compared to the other creatures living there - nematodes, bacteria, fungi, protozea, spiders, springtails, mites, ants, millipedes, scorpions, beetles and sowbugs. Sometimes these act as worm food, sometimes they live in the worm's gut. They have a complex relationship that soil biologists call a food web.
Scientists specializing in earthworms are called oligochaetologists. Darwin was the first to recognize the importance of earthworms, and he wrote a book about them. But even today, earthworms are still not appreciated fully, understood well, and not well classified.
Earthworms are incredibly powerful and important. They can exist in huge numbers. There may be a million worms in an acre of garden soil. By ingesting earth, passing it through their bodies and excreting it as rich fertile castings, they change the earth radically. By making the earth spongy and friable they enable it to hold and absorb water better. They enable the number of microorganisms and nutrients in the soil to increase. In short, they act like a plough.
'Earthworms can be so beneficial, or so destructive. They are literally ecosystem engineers. They are at the very base of the ecosystem. Their actions drive everything else that happens.' (Cindy Hale, ecologist)
Earthworms can ingest pesticides and pollutants and survive. They have been used to monitor pollution in soil, and scientists are currently working on ways that they can clean up pollutants in the soil.
'Earthworms are the custodians of the planet. They were here for millions of years before we came along. They survived the extinction that killed off the dinosaurs. I imagine they'd do just fine if something came along and wiped us out, too ... we should remember one thing: we need worms more than they need us. (Amy Stewart)
If you want to know more, read the book. It's easy to read, fascinating and quirky.
Verdict: Very highly recommended.
The photo competition is run by The Nature Conservancy Australia. Australian citizens or residents are eligible to enter by submitting their favourite photos showing any aspect of Australia's diverse range of habitats. More info at