Young and old animals, males and females: each individual use an area in their own specific way. Once there are several male animals in a natural area, they will compete over females. Bulls tend to make 'bull pits' to impress each other. Many pioneer plants are highly dependent on these sandy, open areas, as do lizards, digger wasps and sand bees. Old bulls or ejected young stallions occupy parts of a landscape that other animals don't tend to visit. To compete for hinds, male red deer show up in different parts of their habitat during the rut, than they do during the rest of the year. On the other hand, protection from predators actually drives animals back together. Food, mutual combat and predation thus determines both the composition and size of herds and the distribution of animals within the landscape. As a result, the spatially varied grazing behaviour creates a rich and biodiverse landscape.