 There has been some concern that the proximity of the drill to humans due to deforestation, hunting, and consumption could result in zoonotic disease transmission.The Bioko drill has been suggested to be an important link in the study of Simian Immunodeficiency Virus due to its long history of isolation from the mainland.Independent evolution of the disease in the Bioko drill for 10,000 years has allowed comparison with the mainland drills, and offers an observation into macroevolution.