Disease stymied
Though there are more than 160 species of the plasmodium parasite, only four infect humans. Amongst the two common ones, Pf is more closely related to the parasite that causes malaria in chimpanzees and birds. Pv, in contrast, is more like the one that affects macaques, a tropical monkey. Chimpanzee malaria and Pf diverged about five to seven million years ago