Choice chamber – taxis and kinesis in woodlice, maggots and fruit flies
BiologyHuman & Animal PhysiologyAges 16–17
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Sign in to playA virtual behaviour practical: put woodlice, blowfly maggots or fruit flies in a choice chamber or a T-maze with light and dark halves, humid (water) and dry (silica gel) halves, or ripe banana, vinegar or dilute ammonia at one end. The animals move by taxis (directed) or kinesis (changes in speed and turning rate). Count the animals on each side every 30 seconds, repeat trials, swap the sides as a control and run a chi-squared test against an even distribution.
Lesson: Innate behaviour: taxis and kinesis – choice chamber practical
What it shows
Simple animals reach favourable conditions without thinking. In taxis an animal moves in a direction set by the stimulus, towards it or away from it, like maggots crawling away from a lamp. In kinesis the stimulus has no direction: the animal moves faster and turns more where conditions are poor and slows down or rests where they are good, so it gathers there over time, like woodlice in humid air. A choice chamber tests these responses, and a chi-squared test shows whether the final counts differ from an even split by more than chance.
How to use
Choose Apparatus, Animal and Set-up, then press Release animals. Counts on each side are recorded every 30 seconds; use Run to end to finish a trial quickly. Press Return animals to habitat, then run more trials, using Swap sides as a control. Tick Show tracks and compare Taxis only with Kinesis only. Click a row in the trials table to see the chi-squared working.
Parameters you can change
- Apparatus Choice chamber, T-maze
- Animal Woodlice, Maggots (blowfly larvae), Fruit flies
- Set-up of the two sides Dry (silica gel) – humid (water), Light – dark, Light/dark × dry/humid (4 quarters), Ripe banana – water, Vinegar – water, Dilute ammonia – water, Both sides the same (control)
- Response model As the real animal, Taxis only, Kinesis only, No response (random walk)
- Animals per trial 5–30
- Length of each trial (choice chamber) 2–20 min
- Random seed (the same seed gives the same results) 1–999
- Show tracks
Questions to explore
- Why do woodlice gather in the humid half even though kinesis gives them no information about direction?
- Why should you swap the two sides between trials and also run a trial with both halves the same?
- A single trial of 10 animals is not significant but the pooled trials are: what does this tell you about sample size?
