I'm a Worm Get Me Out of Here

These resources allow students to explore natural selection using different coloured baits (spaghetti ‘worms’) that are selected and eaten by birds. Uneaten ‘worms’ are counted after predation and the ‘worm’ population is replenished in proportion to those colours which remain. After several cycles of predation and ‘breeding’, the proportions of the colours in the population change, simulating directional selection. The work is equally well suited to schools in urban and rural areas, and provides opportunities for sharing data between schools or classes. Students can also test which factors influence the rate at which the two types of prey are selected by the birds. What happens when you change the colour of background that the worms are placed on? The location of the test area? The size of the worms? The Survival Rivals resources were produced by the Wellcome Trust.