Interesting article, but it seems to me that this is one of those instances where science takes nature farther than it might go on its own. I can't see that these tests prove anything other than that we can induce a reaction between prions from one animal brain protein from another. I don't believe that this alone can be used as a predictor of real life occurrences. There are a lot of things that we can force to occur in a test tube that would never occur by themselves.