World ecoregions. (A) Clusters of vegetation features of the world computed through an unsupervised classification on Principal Components Analysis decomposition of monthly normalized difference vegetation index (NDVI) values at a resolution of 0.1°. Small islands were removed to improve the presentation. Only the ecoregions providing most information about A. marginale distribution according to a Discriminant Analysis were included, grouped in four main clusters and arbitrarily numbered. Overlying records of A. marginale are in black. (B) Monthly NDVI values detected for each ecoregion clusters (plotted with the same colors as in A). (C) Monthly accumulated temperature and rainfall recorded for each ecoregion cluster.
Estrada-Peña et al. BMC Biology 2009 7:57 doi:10.1186/1741-7007-7-57