Originally aired during the week of May 17, 1999
It can move objects many times its own weight. It can lose its head - and grow back another one. It is both male and female at the same time. Best of all, it can eat dirt. Does this sound like some kind of critter with super powers? Earthworms are pretty incredible creatures, in their own way. While we rarely seek them out unless we're planning a fishing trip, worms are all around us, all the time - or I should say, underneath us all the time - doing very important work that we should stop and appreciate once in a while. In fact, we'll have a small worm farm on display at the Montshire Museum Friday night and over the weekend. It's part of our Passengers Party, which celebrates all sorts of amazing creatures that are fellow travelers on planet earth. The worms are special guests of ours so please be polite and don't tell any fishing jokes.
Earthworms are annelids, a word derived from Latin meaning "rings." You'll note that worms are made up of dozens of rings or segments. It is a myth that you can divide a worm in half and have each half grow into a complete new worm. But to some degree, worms can regrow segments that have been cut off. A worm can lose its head, but it'll grow right back as long as too many segments haven't been sacrificed. Each ring or segment on the worm has tiny bristles which help the creature move along the ground or burrow through the soil. There are hundreds of species of earthworms around the world - some measure only about one inch long. The giant earthworm of Australia is no garden variety worm. It can measure ten feet in length and has a girth of up to three inches! Not the kind of worm I'd like to meet up with on a dark and stormy night!
Earthworms have been called "nature's ploughs," "soldiers of the soil," and "intestines of the earth." That last one was from Aristotle. So what do worms do that earns them such high praise? Hey, it wouldn't be much of a world without earthworms. Worms are long, thin digestive tracts that ingest large amounts of dirt. As a result of their tunneling, worms break up the soil, providing oxygen for roots of plants. Worms help the soil hold more water. Worms clean up dead organic matter by eating it and turning it into castings, which may be the world's best fertilizer. Basically worms manufacture topsoil. Naturalist Peter Farb writes that worms pass more than 40 tons of castings per acre of territory. Charles Darwin himself made a special study of earthworms. He doubted whether there was any other animal which played such an important a role in the history of the world.
Earthworms are hermaphrodites, which is a fancy way of saying they are male and female at the same time. Sound complicated? It is. The earthworm does not use its dual sexual organs to fertilize its own eggs. Instead, worms seek mates, with each partner producing eggs. On warm, moist nights, you might see dozens of mating worms coming up out of their burrows. Just before hatching, the egg cocoon resembles a purple grain of rice. The young worms are white when first hatched, and begin to turn a reddish brown after their first meal of soil. Egg cocoons can remain frozen in the soil over winter and hatch when the thaw comes. We'll have a small worm farm on display at the Montshire Museum Friday night and over the weekend. It's part of our Passengers Party, which celebrates all sorts of amazing creatures that are our fellow travelers on planet earth.
The presence of earthworms can't help but improve the health of your lawn or garden. Under the right conditions, they reproduce quickly - ten pounds of earthworms can produce two tons of kin in just two years. But if the soil is too acidic, the worms won't thrive. Earthworms live in dark, narrow underground burrows. They cannot tolerate heat and sun, so during the warmer months they come up to the surface only at night. Though they have no eyes, worms possess light sensitive cells and can "sense" light in some way. Worms do not hear the way human beings can hear. But they are very sensitive to vibrations. For instance, they can sense the movement of a robin, bobbing along, looking for a high protein meal. Come to Montshire this evening from 4-6:30 pm and introduce yourself to some friendly local earthworms and dozens of other creatures at our first annual Passengers Party.
