A discipline first outlined in 1987 that studies the spatial distributions of genetic lineages among related species or within populations of a species. It seeks to describe not only when but also where species diverged, and how historical changes in topography, climate, continental drift, and other factors have determined the genetic makeup and distribution of their descendants. Changes in the composition of certain parts of the genome, for instance mitochondrial DNA and ribosome genes, provide the raw data for tracking evolutionary history (i.e. phylogeny) at different timescales, whether over millions of years for speciation events or thousands of years for changes in populations. The resulting insights enable modelling to predict effects of, for instance, climate change, habitat loss, and overexploitation by hunting, thus providing valuable information for species conservation.