FIGS is based on the Darwinian principal of natural selection. That is, the presence of adaptive traits within a plant population, in this case landraces, primitives or wild relatives of crop plants, will be influenced by long-term environmental factors such as climate, and soil conditions.
The FIGS process works by using environmental data associated with germplasm collection sites to “predict” where certain traits are most likely to have emerged due to selection pressures imposed by the environmental conditions. Specialized GIS and statistical tools are used to do this.
A full link to FIGS and their use can be found HERE