What space pillbugs?Have you ever before turned over a absent or one old board in her backyard and also discovered under a small, hard-shelled biology that each other a miniature armadillo? when you choose up the bug in her hand, did it role up right into a near-perfect ball? such armored creatures are called sow bugs, and also the sort that roll up right into a ball, or pill shape, often are called pillbugs. Technically, sow bugs and pillbugs are well-known as isopods, which way "the legs room alike." Isopods room not insects, but crustaceans - land-dwelling family members of crabs and also lobsters.

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What do pillbugs look like? Pillbugs room wingless, oval or slightly elongated isopods about 1/2 customs long. They are colored a slate-gray, and their human body segments resemble armored plates. Pillbugs, or "roly-polys," have three body parts: head, thorax, and also abdomen. They also have 7 pairs that legs.

How carry out pillbugs live?Pillbugs room slow-moving, crawling creatures, and also they space cold-blooded, which means their body temperature is regulated by the neighboring environment. In the Columbia Basin, you can discover pillbugs in many places, but particularly in gardens, along residence foundations, and sometimes in basements. Although this creatures space common, you hardly ever see them throughout the day since they prefer dark, moist places - under rocks, boards, bricks, trash, disc vegetation, or just beneath the floor surface. Mulches, grass clippings, and also leaf litter often carry out the decaying organic matter these creatures must survive. Just at night execute they emerge to wander around.

Pillbugs can breed throughout the year. The woman carries the eggs in a brood bag on the underside of she body. Often, there space as many as 200 eggs every brood. The eggs hatch in 3 to 7 weeks, and the young remain in the pouch another 6 to 7 weeks. Once the young leave the pouch, they never return. Some species produce only one brood every year, yet others may produce two or more.

Isopods, like insects and their relatives, must shed their hard outer skin or exoskeleton come grow. They perform this a dozen or much more times during their lives. Pillbugs typically hide when they burned their skin since they are especially vulnerable to opponents at this time. The mean life span of most isopods is about 2 years, but some have actually lived as lengthy as 5 years.


"Science is created of facts as a residence is that stones. Yet a collection of facts is no an ext a scientific research than a heap the stones is a house." Henri Poincare

Keep in psychic this fact sheet is intended to be offered only together background details to support your effort to encourage inquiry-based science, i m sorry parallels the method scientists uncover knowledge and solve problems.


1. Equipped with a flashlight and also jar, girlfriend can quickly find and also collect pillbugs in the backyard. You also can catch them making use of a totality potato as bait. Here"s how: To do the potato trap, bore a 3/4-inch hole with the potato lengthwise, then close up one finish of the hole with a tiny piece of the potato plug. Location the "trap" in the garden or any kind of other location where sow bugs and also pillbugs are abundant. Cover the trap with leaves, and also leave it alone a few days. The pillbugs will come and feed within the feet in the potato. To remove them, place the opened over a jar, and strike the potato to dislodge them. The potato trap is especially helpful for collecting tiny or young isopods and rare species, too.

2. Check pillbug responses to moisture.Here"s how: take it a batch of tool to big pillbugs (8-10 specimens) and also place castle in a petri dish or jar on dry filter paper. Store the container in dim light, and also observe the reaction the the bugs because that 2-3 minutes. How do the pillbugs react? record your observations. Now put the exact same pillbugs in a container with simply a small piece of wet paper. What execute you observe? Why perform you think pillbugs reacted the way they did? Think about where you uncover pillbugs - in damp or dry areas? go you know that pillbugs have actually gills and they carry out not retain water well? in ~ a minute or 2 you should have actually seen them clump together as soon as they were put on the dried paper, indicating a require to alleviate water loss from your bodies. Many pillbugs plot "normally" as soon as the family member humidity is moderately high (50-70%), the light is dim, and the temperature is close to indoor conditions or contempt lower.

3. Check pillbug responses come temperature. Here"s how: Place 4 to 6 pillbugs in a small jar v a cover, and float the seasoned on water in a pan. Include ice cubes and a thermometer, and also stir tenderness so as not to guideline the jar. Watch the reaction that the pillbugs. Now remove the ice cream cubes, and gently heat the water. After 1 minute, keep in mind the temperature ~ above the thermometer and also write down the reaction of the pillbugs. Proceed to record the temperature and your observations. When the temperature it s okay close come 40°C remove the pillbugs or lock will go into heat stupor, which might kill them. Did you recognize that pillbugs sluggish down their movements and may also stop moving as the temperature philosophies 0°C? Pillbugs will speed up their motions as the temperature rises and they end up being frantic by the time the temperature reaches 40°C.

(Experiments through Louis F. Wilson, Michigan Entomological Society, room of Entomology, Michigan State, University, eastern Lansing, Michigan 48823.)


The Pillbug Project, grades 3-7, national Science teachers Association, 3140 N. Washington Blvd., Arlington, Virginia.Project Wild, grades 1-12, P.O. Box 18060, Boulder, Colorado.

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Rolypolyology (Backyard Buddies), Michael Elshohn Ross, 1995. Carolrhoda Books, Minneapolis, Minnesota.



Initial breakthrough and print of this fact sheet was funded by one Eisenhower provide to the Partnership for Arid soil Stewardship. Written by: Randy Reed; series Editor: Georganne O"Connor; Design: WinSome Design; Printing: Eagle Printing and Graphic Design; an initial Printing: December 1997; web Development: WinSome Design.