Tuberculosis, Seals, and the Americas

When the Europeans came to the Americas, they came with technology more advanced than the American Indians already here, but guns did not win the continent for Europe.  It was disease, strains of bacteria that were commonplace in Europe but unseen in the Americas.  The native population had no resistance, no antibodies, and as a result, diseases like tuberculosis wiped out 95% of the American population in less than 100 years.  That left the door wide open for European opportunism.

It was always assumed that the American Indians had no antibodies for these diseases, but a recent examination of three Peruvian skeletons dating back a thousand years calls that into question.  They found several signs on the bodies that undeniably point the cause of death to tuberculosis, a disease that wasn't supposed to be in the Americas at that time.  How'd it get there?  The answer, apparently, is seals.  Yeah, they thought it was stupid too, but they ran the data, and it fits.  Seals can carry tuberculosis, tuberculosis can and does easily jump from animals to humans, and most importantly, the type of tuberculosis seals carry match the type found in the Peruvian skeletons.  Turns out there's a lot of different types of the disease, and while the American Indians may have had antibodies for their version, the European version was much nastier.  Not a particularly groundbreaking piece of science, but I thought it was interesting.