"Vampiric" Microbes May Have Initiated Billion-Year-Old Evolutionary Leap

Vampires aren’t mythical creatures. Lampreys, bats and even one of Darwin’s famous Galapagos finches engage in vampirism, along with hundreds of other parasitic worms, mammals, and even snails. Almost a billion years ago, back before there was even blood, it seems that some very primitive forms of life still accessed the nutritious innards of other organisms through violent punctures

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