New genetic data suggests the possibility that tuberculosis may have originated in seals and been transmitted to humans from Africa to South America by seals about 6000 years ago, much sooner than previously thought. There is some controversy about whether this could be the case as there is fossil evidence of tuberculosis-like markers from 17,000 years ago. It's an interesting scientific puzzle. http://www.nytimes.com/2014/08/21/s...-region®ion=bottom-well&WT.nav=bottom-well
Pretty interesting ideas there. The idea being that it was acquired by humans in Africa 5000 years ago, then spread to humans throughout the Old World, as well as sheep, cattle, and (somehow?) seals in Africa. Who then passed it on to South American seals via some mechanism, which were probably killed by sealers in the New World, causing its transmission to those peoples. The human to seal transmission, and the seal to seal transmission seem somewhat unlikely to me, but the whole thing seems possible just improbable.
I tried getting my head around the thought processes of the researchers here and failed. They specifically said that the tuberculosis in the South American mummies was a form of seal tuberculosis and not close to forms of human tuberculosis - yet their answer is that it is human tuberculosis transmitted to South African seals (by..... the humans coughing on them when they were hunting them?), which then presumably mutated into a seal tuberculosis, was transmitted across the Atlantic by wayward seals, passed onto the local South American seal species, and then to humans again. And yet they also, as noted in the article, apparently chose to ignore evidence of human tuberculosis that was earlier than their few thousand year old date. There are a lot of jumps and assumptions in there.
