Final answer:
HIV-1 and HIV-2 originated from different sources related to separate transmission events from SIV, with HIV-1 associated with chimpanzees and HIV-2 related to sooty mangabey monkeys. Their evolutionary paths reflect rapid evolution and adaptation.
Step-by-step explanation:
The direct answer to the student's question about the phylogeny of HIV is: a) HIV-1 originated from a different source than HIV-2.
Explanation: Phylogenetic analysis and comparison of genetic sequences have shown that HIV-1 and HIV-2 viruses are distinct, each having originated from separate transmission events from simian immunodeficiency virus (SIV) into humans. HIV-1 is related more closely to SIV strains found in chimpanzees (Pan troglodytes), while HIV-2 is related more closely to SIV strains found in sooty mangabey monkeys (Cercocebus atys). These findings suggest multiple zoonotic transfers to humans. The evolutionary patterns of HIV are clear, demonstrating rapid evolution and divergence due to the virus's high mutation rate, which leads to a rapid development of drug resistance. The rapid evolution is evidenced by the divergent strains and the capability of the virus to adapt to selective pressures, such as the immune system of the host and antiretroviral therapies. HIV infection being acquired through eating monkeys is a misconception; HIV is primarily transmitted through sexual contact, blood transfusions, needle sharing, and from mother to child during childbirth or breastfeeding. It's also critical to dispel myths and misinformation surrounding HIV, one of which claims the virus can only be spread by certain behaviors or was synthetically created, both false notions.