When you're like me and you live in a place like New Orleans, bugs are pretty much a part of everyday life. If you walk outside for more than five minutes, regardless of the season, your skin gets freckled with mosquitoes, and everywhere you look, there's an aura of gnats surrounding the sago palms. Dragonflies flit and float around plants and pools, and ladybugs wander in aimless loops around our ceilings while we're trying to get to sleep. And while these peculiar six-legged invertebrates may not necessarily be beautiful, they certainly are part of what makes New Orleans what it is. After all, spring just isn't the same when you don't have to cautiously dodge those thorny, neon-green caterpillars sprawling lazily on the gecko-gray sidewalks.
The backyard fountain
The other day, as I perched on the wide slate wall of the terrace in my backyard, I slapped a mosquito that had just come to a landing on my knee and looked out at the spectrum of paper-thin, satin-soft flowers; the bouquets of long, glossy green ginger leaves; and the young live oaks, which were still awkwardly supported with wires and poles all around their skinny trunks, taking in the array of such a diverse ecosystem. As I watched a tiny doodlebug slowly span the leg of a lawn chair, quickly rolling itself into a protective ball at the slightest flinch of my toe, my mind shifted—the wide stretch of grass seemed big to me. How big must it seem to one of the white, microscopic grains-of-sand-with-legs crawling around on the fig ivy? Furthermore, what was I living with? Which bugs ignored me from their tall posts in the holly tree as I walked through the grass? How many macroinvertebrates, with long Latin names more conspicuous than their bodies, hid out under the crunchy yellow leaves that had been discarded by the dusty magnolia tree in the corner of our yard? And what, exactly, was sifting through the soft, velvety-smooth soil beneath my toes, oblivious to the fact that I was separated from them only by a thin layer of grass that had yellowed from the wet New Orleans cold?
Remy with a soil sample
After trekking through my backyard, sifting through dead leaves, and swooping a clean peanut butter jar after passing butterflies and bees in a vain effort to find a few bugs to research, I decided to abandon my original quest to find as many different species of insects as I could. Instead, I began exploring aimlessly, hoping I might find inspiration in some other part of my yard. Armed with a rubber-handled trowel and an armful of tall glass jars, I gingerly walked my way through the muck, pausing on the occasional island of dry grass to dissect the ground in my search for insects. The wide dull blade weakly pierced the ground, and I quickly looked underneath in hopes of catching at least a glimpse of some brightly colored foreign beetle before it made a quick getaway. Instead, the claylike cake sprinkled with grass yielded a tangled knot of wriggling worms. Tiny clots of soil clung stubbornly onto the long, ridged bodies that were so pink and glossy they looked almost raw. I paused, watching the dirt in fascination as the earthworms continued about their business, digging out neat little tunnels just big enough for them to squeeze through as they went along. I piled a few of the worms onto my shovel and emptied them into an old pickle jar, then walked about 12 feet on, where I made another quick stop to sample the soil.
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Lumbricus terrestris, or a nightcrawler
Again, I immediately came across signs of life. In fact, my shovel brought back another tightly woven nest of worms—but these, although they were about the same length, were much thinner, and they were all a coral pinky-red. Digging a little deeper, I only came across more of these stringy, yarn-thin worms. This led me to wonder a bit more about these fascinating things. What were these two different species, and why were they completely isolated from each other? Why did one species live 12 feet away from the other; why weren't any of them "mingling"? Which niches did each species occupy, and, if put in the same environment, how would they interact—would their interaction result in commensalism, mutualism, or parasitism? I realized that I was most interested in learning more about these strange, legless things that ate creatures in the dirt and flossed their way through the underground, so I emptied my subterranean findings into a wide plastic container and set to work.
It didn't take much searching to find that the thicker earthworms that I'd found first were known as Lumbricus terrestris, or the common earthworm, sometimes called a nightcrawler. And although I couldn't find the red-yarn worms on the Internet or in any books, I suspected that they were the babies of the same species. I inferred further that the red-yarn worms were isolated from the nightcrawlers until they matured.
An earthworm
As with all other organisms, these earthworms occupy a certain niche: They are both decomposers and consumers, feeding on things like decomposing remains, manure, and other small underground organisms like nematodes, bacteria, fungi, and rotifers. Some species of earthworm, like the nightcrawler, can also get nutrition by emerging from the soil at night and taking leaf litter back down with them. Although they don't have teeth, they do have very powerful mouth muscles that enable them to eat. Predators include birds, moles, toads, and centipedes, and certain species of mites can parasitize the cocoons or the worms themselves. Earthworms breathe by coating themselves with mucus, which allows dissolved oxygen to pass into their bloodstream, so living conditions must be moist and humid, or else the worms will dry up. They are ecologically important because they loosen and mix up the soil, enabling water and nutrients to seep through to plant roots. Since they can't walk, earthworms move with tiny bristles, or setae, which are paired on each of their segments and grip onto the worms' tunnel walls. Then the worms push themselves forward with strong muscular contractions (Columbia Encyclopedia).
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