Pick up a glove left in the garden overnight, move a pot from its spot on a wall, or change the position of a neglected garden hose, and you will find a world of little gray crawling creatures, running from the light and trying to hide as quickly as they can.
What are they? In books and science labs, they’re known as isopods, but in popular jargon, these creatures are called wood lice, sow bugs or pill bugs. When really disturbed, some species roll up into a ball, hence their nicknames of roly-polies or even mini-armadillos.
Upon first meeting, it’s easy to call them insects, but they really aren’t. They are members of the great phylum of Arthropods, a group that includes lobsters, shrimps and crabs — except that these isopods have traded the ocean for a life on land. Still, they only survive where their surroundings are dim and damp.
Terrestrial isopods consist of a head, with simple eyes, a thorax and abdomen, a prominent pair of antennae, and seven pairs of legs. Insects have six legs and spiders have eight. Isopods’ usual color is a variation of gray. Many species are fast walkers, a fact easily observed when held in the palm of the hand. With all 14 feet going at once, a lone isopod can make 224 footsteps every second. Imagine if they had shoelaces to tie.
Look for them under things, things like small rocks, rotting leaves, a bit of cardboard, an old shingle, under the aforementioned pot, or working their way through the best part of a compost pile. These creatures actually breathe through gills, not noses, so they must have extra moisture to survive. Isopods roll up when attacked, in order to protect their soft underbelly and to block out air that could dry out their gills and cause them suffocate while waiting for the threat to disappear.
Isopods are harmless and don’t bite. They actually operate as part of nature’s scavenger system, existing by chewing up rotting or tossed-aside plant material, then, like earthworms, enriching soil with their excretions. When isopods eat, they hold their food with the front two of their 14 legs.
Sometimes when times are hard-or there are must too many isopods for a given area, they will eat living plant material and can be a pest in a closed environment such as a greenhouse. They are also part of the food chain with larger creatures finding them a very satisfactory meal.
Like insects, isopods molt four or five times as they mature but they always look like adults, except for their size, proportions and sexual development. After all, there are male and female isopods.
But that’s another story.