The theory I think is most plausible is the Hunter's Theory. The hunters theory basically says, somehow the blood of a monkey got into the blood stream of humans on a few different occasions. This could have been from eating the monkeys or their blood got in a cut of a hunter. On a few of those occasions, the hunter could not fight off the SIV. Since there is a clear link between SIV in monkeys and HIV in humans, it's a hard theory not to consider. The Colonialism Theory is also very possible. It goes along the same lines as the hunting theory, just a different idea of who it was transferred to and why it was transferred. This theory says it was transferred by Africans in labour camps. Because they were treated poorly, their immune systems were very weak. This made them more prone to getting sick and contracting diseases. In these camps, they were mal nutritioned, so a monkey would have been extra source of food. Also these workers would have been using unsterile needles to treat other diseases. Prostitution also occurred in these camps.
I think it is very important to how the virus was transmitted to humans. If HIV and SIV are so closely related, and yet it does not kill monkeys, than maybe we can figure out what it is that prevents that. The minor difference that is in monkeys from humans could maybe help scientists find a cure or a vaccine for AIDS. I think the more knowledge and understanding we have of this disease can only benefit us.
