EVOLVING PASTRY - A METHOD FOR SIMULATING MICROEVOLUTION

It is difficult to provide students with a practical demonstration of the dynamic nature of evolutionary change. We suggest a method for sim ulating 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 hove been eaten the frequencies of the two types in the survivors are calculate d. A new 'generation' of the same size as the first is then presented, with the prey types in the same frequencies as survived predation im the previous generation. This procedure is repeated for as many genera tions as are required. We describe six different types of simulation t hat we have run using this method and suggest several more.