Study on the different behaviors and characteristics of pill bugs
Abstract
In this lab, we collected 10 pill bugs to observe their reactions toward different environments, determining what conditions they preferred and what senses they actually owned.We set up three different experiments consisting of two different connected chambers that gave 10 pill bugs the choice of going into whichever side they liked. We then recorded the number of pill bugs in each chamber every 30 seconds and recorded the numbers on a graph. In our experiment that tested pill-bugs sensitivity to wet and dry climates, we had a chamber that consisted of a wet floor(wet filter paper) and a chamber of a dry floor(dry filter paper). After recording seven minutes worth of data, we find that the majority of the Pill bugs prefer a dryer chamber. We then tested to see if the Pill-bugs could sense temperature by having a cold chamber of 0 degrees Celsius and a room temperature chamber of 22 degrees Celsius. After six minutes of observation, we found that there were equal amounts of pill bugs in each chamber(however that may be due to the fact that the pill bugs in the cold chamber seemed to be too frozen to move and migrate onto the room temperature side). This can also be called a kinesis where an animal moves randomly as a result of external stimuli. In this case, the cold temperatures made the pill bugs curl up and stop moving, probably preventing them from moving out of the cold chamber. Finally, our last lab tested the pill bugs sensitivity to taste as well as touch where we placed some honey in one chamber. After six minutes of observation, we noticed that the pill bugs tended to drift towards the Honeyed chamber of 8 to 2. This is an example of kinesis which is a specific action as a result to a stimulus where the pill bugs moved to the honeyed chamber in response to the sweet taste and scent of it.
various senses of a pill bug
Introduction
In this lab, we will analyze the behavior of pill bugs or more commonly known as roly-polis. First however, we have to understand what behavior is. Behavior is an animal's response to sensory input and can be divided into two categories, learned and innate. An example of learned behavior is if a baby touches a hot pan, it knows not to touch it again because it hurt but an example of innate behavior is when a domesticated house cat who has never learned how to hunt pounces and kills a mouse. Another name for innate behavior "fixed action pattern" which essentially means instinctive behavior that is indivisible and runs to completion. There are two different questions that can be asked about behavior; proximate and ultimate questions. Proximate questions ask how an animal's mechanism works and ultimate questions ask why this happens and how it may have developed historically or functionally. An example of these questions can be seen with birdsong. A proximate question would be something like, how is a bird such as the brown thrasher able to sing more than 4,000 different songs? An ultimate question for bird songs would be why did the brown thrasher evolve to develop capabilities to sing more than 4,000 different songs? Another aspect of behavior is imprinting. Imprinting is related to the early stages of an animal's life where it becomes attached and begins to develop its own identity through what it sees. In young geese, when they are born, the first living they see becomes, in their eyes, their mother and they follow the creature around. A proximate cause for this happenstance is the baby geese imitate their mothers by copying their exact movements and following them around. An ultimate cause for this idea is the baby geese follow their "mother" in order to learn how to survive and be able to pass on its own offspring in the future.
These geese are imprinted that the man is their mother and follows him around
How do these pill bugs associate and act on those associations to move between chambers however? That is through either operant or classical conditioning. Classical conditioning is an involuntary response that ties a nonrelevant sense to another. For example, when a pill bug tastes honey and feels something sticky, it would associate sticky stuff to be sweet and tasty. Operant conditioning is different however in that this involves rewards and punishments to stimulate behavior. An example of this in pillbugs is every time a pill bug goes into the honey chamber, it realizes that it has something delicious to eat and decides to go there every time for sweet food.
Question
Do pill bugs prefer a cooler environment?
Hypothesis
If ten pill bugs are placed in a two chambered structure with one chamber close to 0 degrees celisius, they would stray more towards the cooler side because they are used to cooler and darker areas such as under rocks.
Materials
One soft brush
one two chambered structure
10 pill bugs
2 Ice Packs
1 Timer
2 thermometers
Procedure
1. Place filter paper in both chambers
2. Place ten pillbugs in middle of structure
3. Surround one chamber of the structure with 2 ice packs, one on top and one on bottom
4. begin timer and record the initial amount of pillbugs in each chamber
5. record for 6 minutes
Results Number in Cold Chamber Number in Room Temp Chamber
Time (Mins)
0.0 2 8
0.5 5 5
1.0 5 5
1.5 5 5
2.0 5 5
2.5 5 5
3.0 5 5
3.5 5 5
4.0 5 5
4.5 5 5
5.0 5 5
5.5 5 5
6.0 5 5
This data shows that within the first thirty seconds of the experiment, three more pillbugs moved from the room temperature chamber to the cooler chamber. This shows that a large amount of pillbugs actively moved into the cooler chamber. However, this can also be an example of kinesis because the pillbugs may not have had the chance to move back as the cold chamber drastically slowed their movements and practically froze the pillbugs.
Conclusion
Through this experiment, we can see that pillbugs are able to sense a cooler temperature, confirming the presence of touch as they were able to feel a cooler chamber. We also see that a large number of pillbugs voluntarily moved to the cooler chamber thus showing that some pillbugs do prefer a cooler climate. We kept both chambers dark so as not to add two different variables of light and dark but we still saw that the pillbugs were equally divided between room temperature and cooler temperature chambers. We also saw that while in the cold chamber, the pillbugs were stacked on top of each other, and mostly curled. That might have been an instinctive mechanism triggered when they found the chamber to be cold. This shows that some pillbugs may have a preference for a cold chamber but some could also have a preference for the room temperature chamber. A common mistake we may have made is the pillbugs may have randomly moved about and froze while in the cold chamber and making them unable to move back into the room temperature chamber.