Modelling the evolution of plant dispersal

Plants exhibit natural defences against threats to their habitat, yet these mechanisms are poorly understood. New analytical models offer improved insight into the effectiveness of these self-preservation tactics in an increasingly hostile environment.

Climate Change and Environment

The importance of biological diversity, or biodiversity, has become better understood over the past several decades. Without biodiversity, mankind's existence could be threatened as the key interactions between organisms and ecosystems break down. Great economic and cultural benefit is also derived from biodiversity. Loss of biodiversity is therefore a frightening prospect. Yet in many areas of the world, the rapid pace of development is destroying natural habitats. As a result, numerous species of plants and wildlife are threatened by possible extinction. As part of a European response, the PLANT DISPERSAL project funded frontline research on the effects of habitat fragmentation on several plant species. As other organisms, plants have built-in natural defence mechanisms, namely dispersal, but these are not well understood. Previous studies have analysed the genetic and demographic aspects of dispersal separately. The innovation of PLANT DISPERSAL was to attempt to address these two issues simultaneously. This is crucial since it is known that complex interactions exist between these two elements. The processes were parameterised and incorporated into models. Numerous simulations with the model were run to examine possible outcomes in the metapopulations. The results indicate the importance of the scale and pattern of fragmentation. Furthermore, it was noted that fragmentation effects changes upon other plant characteristics not related to dispersal. These changes must be taken into account in order to understand the overall impact. Output from the model simulations will be particularly useful for landuse planners, wildlife managers and so on. For example, threshold values, which should not be exceeded in order for species survival, can be determined for various species under different landuse regimes. The puzzle is not yet complete. Further research is necessary to ensure proper management of natural resources and maintenance of biodiversity, but an important step in the right direction has been made.