This is one the most extraordinary and convoluted evolutionary tales that I have ever heard. It’s the origin story of a group of viruses called REVs. It’s the tale of how naturalists and scientists inadvertently created a bird virus out of a mammalian one through zoo-collecting and medical research.
To understand it, we need to go back to 1957, when the very first REV was isolated from a turkey in America.
Or we should travel back to the years after World War II, when REVs spread around the world in vaccines that were meant to stop poultry diseases rather than cause them.
Better still, we should go back to the 1930s, when scientists analysed the blood of a beautiful Asian pheasant (captured from New Guinea and living in what’s now the Bronx Zoo) and found a new species of malaria parasite (which was a huge boon for malaria research but is now lost to science).
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