An Investigation into a Woodlice's Preferred Choice of Environment.

Authors Avatar
AN INVESTIGATION INTO A WOODLICE'S PREFERRED CHOICE OF ENVIRONMENT.

SCENARIO

When he was gardening, Kevin noticed that he rarely ever saw woodlice, but when he lifted stones or wood etc. The woodlice found underneath seemed to run in all directions.

HYPOTHESIS

Woodlice prefer dark, damp and warm surroundings to light, dry and cold environments, by setting up a choice chamber with all of the available conditions within, I will determine that woodlice do prefer a wetter, darker environment to a lighter, drier one. And I predict that you will find that the woodlice mover quickly to the wet/dark compartment, more so than the other three.

Null Hypothesis:- Woodlice do not have a preferred environment for living in. Any difference that occurs will be due to chance factors.

BIOLOGICAL KNOWLEDGE

Woodlice appear as insects but in fact they are crustaceans. They are one of the only crustaceans known that have adapted to living on land instead of water. Like other insects, they have no shell, and they possess no waxy cuticle, which helps prevent water conservation. Because of this, woodlice are prone to losing water easily via evaporation due to their outer skin being very permeable. This is why they prefer to remain in damp environments. It is said that in dry air, within two hours they will be dead, (www.science.org.uk).

By observing them in different environments (e.g. light/dark, wet/dry), a significant difference in their behaviour and reaction should be seen. Woodlice tend to move quicker in dry places than damp places. You may also see them 'clump' together. This helps them to reduce their water loss as it reduces the surface area that is in the open air, as by less air passing their outer layer, less water is lost in that way. This is the same as when some plants that may have adapted to hotter climates have sunken stomata. This serves the same purpose.

Woodlice lack the waxy cuticle that many insects and also plants have to reduce water loss by evaporation, this makes them very different from them. this is why woodlice are very dependent on the conservation of their moisture.

When exposed to light, woodlice are said to be negatively phototaxis, a reason for this could be the heat element that is associated with light. If a mammal encounters a lot of heat, it will produce sweat to cool its body down. This causes the amount of water conserved in their bodies to reduce. The same will occur in a woodlouse and therefore they will lose some water, water which is vital for them to survive, because of this, woodlice will attempt to move away from the light into more darker regions, where they hope it will also be cooler.

It says that when exposed to different temperatures, woodlice will exhibit a non directional response - orthokinesis (speed of movement). Meaning that when exposed to higher or even lower temperatures than they prefer, woodlice will move, attempting to find a more suitable environment.

Woodlice will also exhibit a noticeable response when exposed to a different humidity level. They will move with increased speed (orthokinesis), and with a decrease in the rate of turning also, (klinokinesis) in dry conditions, and moving at a slower rate of movement in more humid conditions. Thus, resulting in the woodlice accumulating in more humid regions.

Another effecter on a woodlouse's movement is whether or not their body surface is in contact with any other object (including other woodlice). They exhibit a positive thigmokinesis when this occurs, and will move around so that the maximum amount of their body is touching something else, whether it be a rock or another woodlice. This results in the woodlice forming clumps. By doing this, it reduces the amount of water lost by diffusion of their outer shell. The woodlice in the middle consequently lose less water than those on the outside, and therefore after some time they will all switch places to ensure that they are all conserving as much water as is possible.
Join now!


It can be said then, that woodlice have a preference for dark, damp, fairly warm surroundings. This is true as woodlice tend to be found under rocks, stones and wood. It is clearly dark and damp underneath these, and would also be fairly warm as heat cannot be lost easily as wind may not pass easily underneath the wood etc, making it cooler.

INTRODUCTION

This experiment is to test the preferred environments of woodlice. As is said above, it is said that woodlice prefer fairly dark and damp environments to live in as compared to drier ...

This is a preview of the whole essay

Here's what a teacher thought of this essay

Avatar

*** A good description of the investigation although in places more detail would have been helpful. Some errors and inconsistencies in the experimental design throw uncertainty on the results of the statistical test, and account for this only gaining 3 stars.