They are not well adapted to a warm, dry atmosphere and must be kept moist and in a cool position, preferably in the dark. If you do not maintain a colony of woodlice in the laboratory, collect woodlice from an outdoor environment, keep for a short period and return them to their source as soon as possible. This will provide a source of material for observation as well as extending the range of microhabitats in the area. Where your school has an environmental area, placing pieces of wood, bark or stone on the soil will encourage colonisation by woodlice. Add a lump of cuttlefish or chalk (natural, not blackboard chalk) to the soil to provide a supply of calcium carbonate. If this does not happen, or the animals are intended for use in choice-chamber work, it is worth ‘seeding’ it with individuals of the same species – the animals should look the same! Then bring the container and contents indoors to prevent further colonisation.Īdd food at intervals: plant material such as potato, carrot and other root vegetables cut up into medium-sized pieces. If kept outdoors, such an environment will often be colonised by woodlice naturally. Put a variety of stones, bark and rotting wood on the soil for the woodlice to live in. Place it in a relatively cool and sheltered place out of direct sunlight. Keep the container covered to exclude light and retain moisture. They survive in any reasonably-sized container such as an old aquarium or trough full of moist soil and leaf litter. Collect and transfer them using pooters or small artists brushes.Ģ Woodlice: the CLEAPSS Guide L56 'Housing and keeping animals' gives the following information about woodlice. Distribute beetles in Petri dishes or specimen tubes. Sieve the beetles from the flour before the investigation starts. You can rear them easily in a jar of wholemeal flour. Either species of Tribolium is suitable for these investigations. confusum and is therefore not such an important pest in temperate climates. It needs a higher temperature to complete its lifecycle than T. Tribolium castaneum (the red rust flour beetle) is commonly used in the laboratory. Tribolium confusum is probably the most common flour beetle in mills and bakeries. Read our standard health & safety guidanceġ Tribolium: Tribolium is a small flour beetle that attacks cereals and cereal products and is a pest of stored food. Explain the statistical test and analyse the data, possibly in the next lesson. Run the investigation and collect the data. Ask students to develop a hypothesis to test – relating to damp/dry conditions, light/dark conditions or the presence/absence of another manageable substance (such as the animal’s main foodstuff). Students practise manipulating the apparatus and handling the invertebrates appropriately. Lesson organisationĭemonstrate how to set up the choice chamber and how to introduce invertebrates to it. If the adjacent area is preferred, the animal reacts by reducing speed of movement and turning rate so it is more likely to stay in the preferred conditions. These may result in overall movement out of one area into another. You can state that woodlice do have a preference for one set of conditions over another.Īnimal behaviours in choice chambers may show directional responses (movement directly towards or away from particular stimuli), or may show behaviours such as increasing speed and increase in turning rate. Use a test such as the X 2 significance test to establish whether the final result is significantly different from the expected distribution. After a fixed time, compare the difference between the distribution you would expect if the null hypothesis were true (woodlice distributed 50:50 between damp and dry areas) and the distribution achieved in the laboratory. For example, a null hypothesis might state 'Woodlice show an equal preference for damp and dry areas in the choice chamber'. Investigations using a choice chamber often depend on developing a null hypothesis with which the final result is compared. You can then introduce small invertebrate organisms into the chamber, at different starting points, observe their movements, and record their distribution after a fixed time. These notes explain how a choice chamber is set up, and how to use one to provide adjacent environments with different environmental conditions.
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