geometric series A numerical and graphical description of the relationship of species in a community according to their importance values. Curves approximating to a geometric series are common in pioneer or ephemeral communities. In theory, the more successful species restrict other species to the remaining niche spaces (the pre-emption hypothesis) by occupying a larger proportion of the available niches. If the most successful species occupies 75 per cent of the available niche spaces, and the next species a similar proportion of the remaining spaces, and so on, then a geometric progression of importance values will result.

geometric series A numerical and graphical description of the relationship of species in a community according to their importance values. Curves approximating to a geometric series are common in pioneer or ephemeral communities. In theory, the more successful species restrict other species to the remaining niche space (the pre-emption hypothesis) by occupying a larger proportion of the available niches. If the most successful species occupies 75 per cent of the available niche spaces, and the next species a similar proportion of the remaining spaces, and so on, then a geometric progression of importance values will result.