Science journalist Carl Zimmer explains how viral infections throughout history have affected the human genome. Viruses make up "about 8 or 9 percent" of our genome says Zimmer. Startlingly, human childbirth would not be possible without a viral mutation.
The frontier of biology these days is the genetics and ecology of bacteria, and the frontier of THAT is what's being learned about viruses. "The science of virology is still in its early, wild days," writes Carl Zimmer. "Scientists are discovering viruses faster than they can make sense of them."
The Earth's atmosphere is determined in large part by ocean bacteria; every day viruses kill half of them. Every year in the oceans, viruses transfer a trillion trillion genes between host organisms. They evolve faster than anything else, and they are a major engine of the evolution of the rest of life. Our own bodies are made up of 10 trillion human cells, 100 trillion bacteria, and 4 trillion very busy viruses. Some of them kill us. Many of them help us. Some of them are us. Viral time is ancient and blindingly fast. - The Long Now Foundation
Carl Zimmer is the author of several popular science books and writes frequently for the New York Times, as well as for magazines including The New York Times Magazine, National Geographic, Science, Newsweek, Popular Science, and Discover, where he is a contributing editor. Carl's books include Soul Made Flesh, Parasite Rex and Evolution: The Triumph of An Idea. His latest book is A Planet of Viruses.