Animal Behavior Lab

Pill Bug Lab Write Up

Abstract

In this lab we took our first look at behavior in organisms by examining pill bugs in different environments. Our first experiment tested whether 10 pill bugs would choose to go into a dry or wet chamber if they could move between both at any time.  We tested this at first with no light in either chamber and then light in both.  In the next experiment we saw if they would choose to go to a side with rocks in it or a flat side. For the final experiment we tested to see if they went into a side with honey or a side with no honey.

Introduction

Behavior is how one acts or conducts alone and with others.  Proximate questions are based on the reaction to outside stimulation of the organism.  Ultimate questions are aimed towards things that the organism is inherently due to genetics and evolution.  For example a proximate question about bird song would be what call does a bird make when it is in danger or needs help. An ultimate question would be what tone does the bird hit.  This is ultimate because a bird's song tone would be dependent on what type of bird it is and how it has evolved.  This is why organisms have fixed action patterns like a fish swimming.  This is what is needs to do to get water to flow through it's gills.  However imprinting can affect these actions.  A proximal cause of imprinting could be that for many generations a population of animals didn't hunt, they gathered and stored.  If that population did this for many generation it would forget how to hunt and if the gathering was no longer possible the population would not be able to hunt due to imprinting.  The universal cause of imprinting is learning.  In geese you can not take farmed animals and release them back into the wild.  They have learned that they will get fed and do not need to look for food or means for survival.  This leads to taxis and kinesis behavior.  Taxis behavior is a directed response to something like a tree or plant growing towards the source of light.  Kinesis behavior is completely sporadic on the other hand.  For Example, when a deer gets shot during a hunting trip if it lives it will just bolt in any direction and keep running until it dies. When looking at behavior it is also important to note classical and operant conditioning.  In classical conditioning things are connected in the brain to one action.  For example after a few years in public school, kids associate the bell with recess or lunch. When the bell rings they know to go to the lunch line or go out and play.  Operant conditioning is when things are remembered in the brain by enforcement or punishment. A dog will learn to roll over if he know that he will get a treat after. Positive re-enforcement to the good and negative to the bad.  Knowing all of this we looked at pill bugs and how they responded to different environmental factors.

Hypothesis

For the first experiment we thought: if given the choice then the pill bugs would go to the moist chamber because it is more like their natural environment under rocks.  For the second half we thought that the pill bugs would still prefer the moist test chamber but would be more active in the light.  In the next experiment we predicted if one chamber had rocks then the pill bugs would prefer this chamber because it is also closer to their natural environment.  The third experiments hypothesis was that if one chamber had honey in it then the pill bugs would prefer it because it would be more damp then the chamber without honey.
Materials

2 Test chambers with a pathway between them

10 randomly selected pill bugs

1 pipette full of honey

25 Fish Aquarium Blue Rocks
1 Timer

Procedure and Results

For each lab we started by scattering the pill bugs near the connection between the two chambers so that the initial results would not be too biased. We marked how many pill bugs were in each chamber every 30 seconds.  

Blue= Wet, Red=Dry

Blue=Rocks, Red=Flat

Blue= Honey, Red= No Honey

Conclusion

In the first experiment we learned that when it was dark the pill bugs did not move much. As soon as there was light in the test chambers though, the bugs preferred the moist test chamber.  Due to the light this could be kinesis behavior, but the bugs definitely crowded to the damp chamber.  In the second experiment we learned that the pill bugs preferred the side with the aquarium rocks. A few of them tried to get under the rocks like in their natural habitat.  The others in the rocky chamber attempted to use the rocks to escape confinement. In the final experiment we observed that something about the honey attracted the pill bugs to that chamber. This could have been just that the honey chamber was moist or the bugs tasted the honey and liked the sweetness.  In either case the pill bugs preferred the honey coated chamber.