‘Evolving pastry‘: a method for simulating microe volution

Abstract

It is difficult to provide students with a practical demonstration of trie dynamic nature of evolutionary change. We suggest a method for simulating microevolution in which populations of pastry prey ‘evolve’ in response to selection by free-ranging birds. The birds are presented with a population with known frequencies of, for example, two types of prey, they are allowed to feed and after a specified number have been eaten the frequencies of the two types in the survivors are calculated. A new ‘generation’ of the same size as the first is then presented, with the prey types in the same frequencies as survived predation in the previous generation. This procedure is repeated for as many generations as are required. We describe six different types of simulation that we have run using this method and suggest several more.

Keywords:

• Evolution
• Natural selection
• Predation