Figure 32.28 Major Groups of Eutherians Diversified as the Continents Drifted Apart This phylogenetic tree shows the relationships among most of the major terrestrial eutherian groups, the location of the earliest fossils found for each group (also indicated in the color distinctions of the various branches), and the current distributions of the groups. The major splits in eutherian evolution correspond in large degree to the tectonic history of the major continents (see Figures 24.14 and 53.14).