The use of the mounds of Lasius fiavus in teaching some principles of ecological investigation

The mounds built by the yellow hill ant, Lasius fiavus, in British pastures have striking and consistent effects on the patterns of plant species. Winter annuals, for example, are often confined to the mounds, but many rosette perennials, though abundant in the surrounding grassland, are virtually absent from ant-hills. A comparison of the abundances of six or seven species on and off the mounds provides a field practical suitable for senior school students and undergraduates. The students discuss the sampling methods to be used, collect the data, analyse it, and discuss the factors which might influence the relative abundance of the plant species. This paper describes the practical in detail, and provides some background information about the ecology of the ants and some common grassland plants. Some suggestions for individual projects are put forward.