Investigating moisture
Environmental factors affecting animal movement can be investigated using equipment such as a choice chamber. One investigation compares how woodlice distribute themselves between moist and dry conditions.
Apparatus
- choice chamber;
- distilled water;
- a drying agent such as anhydrous calcium chloride;
- gauze platform;
- woodlice;
- soft paintbrush.
Method
- Prepare two distinct regions in the choice chamber: one moist and one dry.
- Add distilled water beneath the moist side and drying agent beneath the dry side.
- Place a gauze platform above the substances so the woodlice remain separated from both treatments.
- Introduce 10 woodlice into the middle of the chamber, where they can move into either region.
- Leave them free to move for 10 minutes.
- At the end of the timed period, count the woodlice occupying each side.
- Carry out at least two further trials and calculate a mean for each condition.
The number of woodlice in each half provides a measure of their distribution under the two moisture conditions.