Figure 4

Co-evolution and cross-species infection of MLV-related genomes among mammals. Host and retroviral phylogenies are shown on the left and right respectively. Horizontal links indicate co-evolution, whereas sloping links show cross-species infection across large host taxa. Thus two closely related retroviruses infect an ape (gibbon) and a marsupial (koala), and two closely related ERV genomes are found in a carnivore (fox) and a ruminant (sheep). Adapted from Martin et al. [79].