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Did you flip a rock today? Below are photographs of what I discovered. As soon as I get linked up with Wanderin' Weeta, I will post a list of the participants so you can see what everyone found.

The rocks:

A pile of what we call "river rocks" used to stabilize a drainage area. This particular area is mowed grass, so it is irrigated often.

You would expect to find an isopod (also called rolypoly or pillbug), after all there's one on the International Rock Flipping Day badge.

But what is that with the isopod?

What is that brownish coiled object in the lower right of the photograph?

It is a tiny snail! There's another with its head out.

It's blurry, but definitely a snail. Finding snails is amazing in this hot, dry climate.

The snail wasn't the only one carrying it's house.

What is the gray object that looks like a small tube of mud? It is moving!

There is some sort of insect larva inside.

I think it is a beetle larva carrying a case. It is most likely a member of the leaf beetle family (Cryptocephalinae). It probably got washed to the drainage area during a recent storm.

Another tiny beetle scurries away.

Mites were common. Here's a brightly colored one.

Spiders were also abundant. This tiny jumping spider seems to have its eyes on something.

Maybe it was trying to catch one of these Indian house cricket nymphs.I don't envy any predator that hunts these.

I know I had trouble capturing them with my camera. The springtails that were everywhere were even worse. I never did get a photograph of them.

Finally, I did find some ants. I posted those results at Wild About Ants.

Overall, I was pleasantly surprised by the number of creatures I found. And in addition to finding different kinds, I also learned a little bit more about my neighbors that live under rocks.

Did you flip any rocks this weekend? What did you find?

For more information about the creatures featured here try:

Isopods

Indian house crickets

Jumping spiders

Mites

Snails and raising snails

Pill bugs, rolypolies, wood lice, potato bugs or isopods, these cute little crustaceans come with a bunch of common names. Add the names for their close cousins the sow bugs (the ones that can't roll up) and the shore isopods called slaters, and you have a dictionary full.

What do you call these seashore isopods?

Today we're going to be using pill bugs, the ones that look like a pill when they roll up.

Although most people associate pill bugs with moist environments,  surprisingly we have pill bugs in the desert that can tolerate a much drier climate. They are common and active residents of our back yard, although they do seem to prefer the irrigated areas.

Pill bugs are fun to investigate.  First, prepare a temporary holding container with a walnut-sized wad of moist paper towel and a few bits of carrot for food. Look outside under stones or logs for pill bugs. Note:  always return the rocks or logs to their original position when through, and be careful if you live where there are poisonous critters that live under rocks. You might want to tip them with a bar.

When you find some pill bugs, gently transfer them to the container. After they unroll, you can look at them through a magnifying lens. Study how they move and their body parts.

Check the "Using Live Insects in the Classroom" Isopod Information Sheet for a detailed description of their morphology.

1. Draw or build a model pill bug.

Gather materials such a paper, cardboard, chenilles and/or clay and create a pill bug model. Pay particular attention to what they look like, because the more details you add, the more realistic the model will be.

2. Do all your pill bugs look alike? We found some of ours were entirely dark gray whereas others had gold or yellow spots on their backs.

Any ideas why pill bugs might be different colors?

3. When the pill bugs roll up, can you still see their antennae? Our desert pill bugs can roll up with their antennae inside, other species can't. Why might that be?

4. Build a simple maze and test some of your ideas about pill bugs. We built ours out of light cardboard, like a cereal box. We taped it down with masking tape so it wouldn't fall on the pill bugs. Be careful that no sticky edges are exposed, because the pill bugs might get stuck. We also found certain pill bugs wouldn't cross the masking tape, so try to keep the tape on the outside of the maze. While planning, you might want to sketch your maze on graph paper or use a computer.

We tested the idea that pill bugs would prefer darkness to light. We also offered them different types of food.

In the video, we wondered if the pill bugs would explore a complex maze with a lot of turns to find food. We set two pill bugs in the maze entrance together. See what happened:

We had fun and learned a lot about how pill bugs behave. Hope you give it a try.

Once we were done, the pill bugs went back to nature unharmed.

For more information and great science activities with pill bugs, I highly recommend:

Rolypolyology (Backyard Buddies) by Michael Elsohn Ross, and illustrated by Darren Erickson

It seems to be out of press, but you should be able to find it at your local library. It is filled with fantastic ideas.

Other pill bug books (linked images and titles go to Amazon):

A Pill Bug's Life (Nature Upclose) by John Himmelman

The Pillbug Project: A Guide to Investigation by Robin Burnett

I'm a Pill Bug (Nature: a Child's Eye View) (Nature: a Child's Eye View) by Yukihisa Tokuda, and illustrated by Kiyoshi Takahasi

Nature Close-Up - Pill Bugs & Sow Bugs and Other Custaceans by Elaine Pascoe

Pill Bugs Up Close (Minibeasts Up Close) (Perspectives) by Greg Pyers

Compost Critters by Bianca Lavies is an excellent introduction to composting. Although it is an older book, the photographs are excellent.

Previous post on pill bugs

For recent weekend science fun posts we have had a couple of walks: a spring flower walk and a flowering tree walk. Now it is time for a change of pace and do a critter crawl.

Have you ever dug through a pile of leaf litter or looked under a log? How about sifted through a compost heap? Take some time to find a quiet, preferably moist, spot where pieces of dead plants are piled and spend a while getting to know the small, but important animals that live there. Prepare to be amazed at how many different tiny creatures dwell in this often-ignored part of our world.

Before you get started, you might want to gather up a few items:

  • A magnifying lens can help you see more details
  • Tweezers, forceps or a small stick to gently move leaves or bark
  • Small paintbrush to remove dirt and move tiny creatures
  • Paper and pencil to make drawings and record results
  • Gloves (optional but helpful)
  • Identification guides, or take a look at descriptions of compost critters like this one at the Junior Master Gardener website

Locate a compost heap, pile of leaves or logs where you have permission to explore. First survey the area. Make sure you and your family are familiar with common poisonous creatures such as snakes or scorpions that might also be found hiding under leaves, rocks or logs in your community. Bees and wasps sometimes nest in the ground too, so exercise caution.

Gently begin to turn over leaves or peel off loose bark. Pay close attention. What kinds of things might you see?

Expect:

  • Insects such as beetles, crickets, cockroaches, ants or earwigs
  • Snails, slugs
  • Spiders, mites
  • Millipedes, centipedes
  • Worms

If you are lucky you might find a few creatures that are children's favorites, the rolypolies or sowbugs (also called potato bugs, wood lice and various other names). Depending on the type, rolypolies and sowbugs are 1/4- to 1/2-inch-long, gray and relatively hard shelled.

If you find some, gently pick one up. How does it react to being picked up? Does it roll into a tight ball? If so, then it is a rolypoly.
rolypoly

Does it simply try to scamper away? Then it is likely to be a sowbug. Sowbugs look similar to rolypolies, but lack the ability to curl up tightly.

sowbug

The rolypolies and sowbugs belong to a group of animals called the Isopoda. "Iso" means same, and "poda" means foot. Carefully tip yours over and see if this name fits. Does all its feet look the same? How many legs does it have? Insects have six legs and spiders have eight legs, do you think it is either of those?

upside down rolypoly

Does the isopod have eyes? Does it have antennae? What are those small spikes sticking out from the rear part?

When scientists carefully examined isopods, and then compared the isopod appendages and other characteristics to those of other groups of animals, they figured out that isopods are closely related to crabs, shrimp and lobsters. They are crustaceans. Tiny crustaceans in your garden or compost heap, isn't that cool?

What happens when you set your isopod back down? Does it run towards the light or away from the light? Does it try to hide or does it curl up? Try thinking up some more questions to ask.

Keep looking through the litter. You will probably encounter a few things less familiar than the rolypolies, but no less interesting. Have a lot of fun while you observe and learn about this hidden world.

If you can't get outside this weekend, then pick up a few books, like the ones suggested below. After reading them, crawl around the house pretending to be earthworms, crickets and isopods.

Rolypolyology (Backyard Buddies)
by Michael Elsohn Ross, Published by Carolrhoda Books, Inc. Minneapolis, 1995. ISBN 0876149018 contains detailed information and ideas for experiment with isopods.

Compost Critters
by Bianca Lavies, Published by Dutton, 1993. ISBN 0525447636 has absolutely stunning photographs of the inhabitants of a compost heap. Amazing!