Wednesday, July 16, 2014

// // Leave a Comment

Backyard Bugs: Roly Poly or Potato Bug or Pill Bug or Wood Lice...

Whatever you call them, roly polys (or potato bugs or pill bugs or wood lice...) are everywhere!  They are great to learn about and fun to carefully experiment with!  Warning: This post has close up pictures of pill bugs!


So what is the deal with pill bug names?!  It can definitely be a bit confusing.  I will be calling them pill bugs, but let's take just a quick moment and talk about names and classification.  Remember how living things are divided?

 Kingdom, Phylum, Class, Order, Family, Genus, Species

Pill Bugs are in the Animal Kingdom, Arthopod Phylum (which includes spiders, insects, and crabs), and the Order Isopoda.  Isopoda includes literally thousands of species that look very similar, but some live on land and some live in the ocean.  The pill bugs that we see all over the world on the land are all in the sub-order Oniscidea, which also includes literally thousands of species (about 5,000 known).  There is no real order to the common names...pill bugs and potato bugs and woodlice and roly polys are all often used interchangeably.  I even learned a new one, Kellerassel, when I asked my friends on Facebook!  (Thank you Maggy!)  Some people like to differentiate sow bugs as isopods that cannot roll up completely in a ball while pill bugs can, but there is no real difference--just different common names.  Most isopods, in fact, cannot roll up completely.  The most notable exception are the pill bugs in the genus Armadillidum, which can even tuck their head inside their shell when they roll up.

Enough with the crazy names!  Let's talk about these amazing little critters!

Pill bugs are found all over the world and are perfectly safe to carefully hold and examine.
Pill bugs are little herbivores and are not picky eaters.  They often live in their food.  You may see small holes in leaves or other decaying plant matter that they made as they ate their way through their home.

While small, they have amazing little bodies:


See if you can spot these body parts on your pill bugs:

1.  Thick protective cuticle.  

2.  Compound Eyes

3.  Long Antennae

4.  4 Pairs of chewing mouth parts

5.  7 pairs of walking legs (in adults) or 6 pairs of legs (in juveniles).  "Baby" pill bugs get their 7th pair of legs after their first molt.

6.  Pleopods and "feathery" gill-like lungs

7.  2 Uropods.  Male uropods are longer than female uropods.

8.  A female carries eggs around in an egg pouch in the middle of her tummy.  Can you find a "pregnant" pill bug?  Once the eggs hatch, she continues to carry the new pill bugs around for a few more days.  When they crawl out of her pouch it looks like they are born live!

More Pill Bug Fun Facts! 

1.  Pill bugs have blue most crustaceans!  This comes from having hemocyanin in their blood.

2.  Many pill bugs live 2-4 years!

3.  Pill bugs "molt" in two steps:  they shed the back half of their shell 2-3 days before the front half!

4.  Pill bugs can drink from their mouth and their anus!  Uropods can sweep water up into the pill bug if they need it!

5.  Pill bugs often eat their own poop to make sure they have enough copper in their body!

6.  Pill bugs need a moist environment.  They breathe through gill-like lungs on the outside of their body and will quickly die if they are not in a moist environment.

7.  Pill bugs are capable of parthenogenesis.

Try this at home or school!

1.  Raise pill bugs!  Set up a terrarium with dirt, leaves, branches, and water.  "Mist" it with a spray bottle if it starts to dry out.  

2.  Design an experiment to see whether pill bugs prefer light or dark habitats.  Hint: use white and black paper.

3.  Design an experiment to see what kinds of food your backyard pill bugs like best.

4.  Design an experiment to see what kinds of "homes" your backyard pill bugs like best.

5.  What else could you do to learn about pill bugs?

Remember to treat all living organisms with respect and care!

This post is part of my Backyard Bugs series!

Click here to learn more about Backyard Bugs!

Amazon Affiliate Links:  

I may share at any of these parties!