Woodlice Investigation
nvestigation into the Factor of Light and Dark Affecting Woodlice
Predictions
It was expected that a woodlice would prefer a damp, dark, but moderately warm surrounding. Normally one would expect to find slaters under logs or concrete slabs in one's garden. Under these large objects, the sun cannot reach directly; therefore it is darker, damper and colder than the surroundings. Nevertheless, in winter we do not see woodlice crawling around very often, and, also at night, it may actually be warmer under such objects, because it looses heat more slowly, so I predict that the woodlice would prefer a dark, damp and a temperature of around 15oC. (The ground temperature of a typical
Scottish day). This preference to dark and damp surroundings is mainly due to woodlouse's inefficient water-storage system. A woodlouse, if exposed to heat or light for too long, can die due to the dramatic loss of water. They prefer a moderate temperature, because they are so small, and can be damaged by frost if they are exposed to the extreme of cold, but they don't want such a high temperature, either, because they would start loosing too much water. I would also expect the woodlouse to prefer a surrounding of slightly higher pressure (1.05 ~
1.1 atmosphere), because water evaporates more slowly under a high pressure. However, this is not investigated in this experiment due to the nature of the choice chamber.
Equipment/Apparatus
10 woodlice, a choice chamber, a piece of muslin net, water, ice, a kettle (to produce hot water).
Variables
There are three small experiments in this report and the variables and constants are:-
Nr.
Variable
Constant
1
The humidity of the air
The temperature of the surroundings
The luminosity
The time allowed for woodlouse to settle
The number of woodlouse
2
The temperature of the air
The humidity of the air
The luminosity
The time allowed
Predictions
It was expected that a woodlice would prefer a damp, dark, but moderately warm surrounding. Normally one would expect to find slaters under logs or concrete slabs in one's garden. Under these large objects, the sun cannot reach directly; therefore it is darker, damper and colder than the surroundings. Nevertheless, in winter we do not see woodlice crawling around very often, and, also at night, it may actually be warmer under such objects, because it looses heat more slowly, so I predict that the woodlice would prefer a dark, damp and a temperature of around 15oC. (The ground temperature of a typical
Scottish day). This preference to dark and damp surroundings is mainly due to woodlouse's inefficient water-storage system. A woodlouse, if exposed to heat or light for too long, can die due to the dramatic loss of water. They prefer a moderate temperature, because they are so small, and can be damaged by frost if they are exposed to the extreme of cold, but they don't want such a high temperature, either, because they would start loosing too much water. I would also expect the woodlouse to prefer a surrounding of slightly higher pressure (1.05 ~
1.1 atmosphere), because water evaporates more slowly under a high pressure. However, this is not investigated in this experiment due to the nature of the choice chamber.
Equipment/Apparatus
10 woodlice, a choice chamber, a piece of muslin net, water, ice, a kettle (to produce hot water).
Variables
There are three small experiments in this report and the variables and constants are:-
Nr.
Variable
Constant
1
The humidity of the air
The temperature of the surroundings
The luminosity
The time allowed for woodlouse to settle
The number of woodlouse
2
The temperature of the air
The humidity of the air
The luminosity
The time allowed