A stochastic model of seed dispersal pattern to assess seed predation by ants in annual dry grasslands

A combined field experiment and modelling approach has been used to provide evidence that ants may be responsible for an observed lower patchiness and higher plant diversity in the neighbourhood of ant nests, within Mediterranean dry grasslands belonging to the phytosociological class Tuberarietea guttatae. The hypothesis was that seeds occurring in clumps may have an higher probability to be harvested than seeds having a scattered distribution. In order to test this hypothesis, four analysis steps have been performed. First, the seed productivity and dispersal pattern was recorded for four plant species found, either more abundant beside the ant nests (Tuberaria guttata, Euphorbia exigua) …