Animal Behavior Annotated Bibliography
Integrated Science 3
Redwood High School
Name:
8/14
Per:
1. Potter, M. F. (1998, April). Sowbugs and Pillbugs. The University of Kentucky Department of Agriculture.
Retrieved August 6, 2012, from http://www.ca.uky.edu/entomology/entfacts/ef439.asp
Sowbugs and pillbugs are crustaceans. They are closely related to crabs and shrimps and are some of the few
crustaceans that live exclusively on land. They primarily inhabit in moist environments outdoors.
“Sowbugs and pillbugs range in size from 1/4 to 1/2 inch long and are dark to slate gray. Their oval, segmented
bodies are convex above but flat or concave underneath. They possess seven pairs of legs and two pairs of antennae
(only one pair of antennae is readily visible). Sowbugs also have two tail-like appendages which project out from the
rear end of the body. Pillbugs have no posterior appendages and can roll up into a tight ball when disturbed, for which
they are sometimes called "roly-polies".”
“Sowbugs and pillbugs are scavengers and feed mainly on decaying organic matter. They occasionally feed on young
plants but the damage inflicted is seldom significant. Sowbugs and pillbugs thrive only in areas of high moisture, and
tend to remain hidden under objects during the day.”
2. Newton, B. (2008, April 21). Kentucky Sowbugs. University of Kentucky Department of Entomology. Retrieved
August 6, 2012, from http://www.uky.edu/Ag/CritterFiles/casefile/relatives/sowbugs/sowbug.htm
“Sowbugs are very common in moist, cool conditions, and are often found under rocks and logs. They feed on fungus
and decaying plant material, usually moving and feeding at night. Sowbugs are preyed upon by many creatures,
including spiders, centipedes, ground beetles, and small mammals. Some sowbugs have foul-smelling, foul-tasting
defensive chemicals which provide some protection from predators. Pillbugs, of course, are also able to roll
themselves into a ball for protection.”
3. University of Arizona Center for Insect Science Education Outreach (1997). Isopod, Pillbug, Sow Bug
Information. Retrieved August 6, 2012, from http://insected.arizona.edu/isoinfo.htm
Sowbugs are classified in the phylum Arthropoda, subphylum Crustacea, class Malacostraca, and order Isopoda.
They have three body parts: head, thorax and abdomen. They have two pair of antennae, simple eyes, seven pairs of
legs, seven segments on their thorax, paired appendages at the end of their abdomen, and vary in color from white to
dark gray.
Adults females have a structure on their underside called a broad pouch that holds developing eggs and embryos,
whereas adult males’ first two appendages are elongated for reproductive purposes.
Juveniles look like adults when released from the broad pouch. They look like adults except for size, proportion, color
and sexual development. The immature sowbugs and pillbugs will molt four or five times. Molting is in two stages.
First the back half molts, then two to three days later, the front half molts. Coloration of both halves may be different
at this time.
“Sowbugs breathe with gills, which limits their range to habitats with high humidity, under rocks or logs, in leaf litter
or in crevices. Some species are nocturnal.”