| A short history of nearly everythingGradually a system evolved in which life was dominated by two types of form-organisms that expel oxygen (like plants) and those that take it in (you and me). Single-celled eukaryotes were once called protozoa (БЂњpre-animalsБЂ«), but that term is increasingly disdained. Today the common term for them is protists. Compared with the bacteria that had gone before, these new protists were wonders of design and sophistication. The simple amoeba, just one cell big and without any ambitions but to exist, contains 400 million bits of genetic information in its DNA-enough, as Carl Sagan noted, to fill eighty books of five hundred pages. Eventually the eukaryotes learned an even more singular trick. It took a long time-a billion years or so-but it was a good one when they mastered it. They learned to form together into complex multicellular beings. Thanks to this innovation, big, complicated, visible entities like us were possible. Planet Earth was ready to move on to its next ambitious phase. But before we get too excited about that, it is worth remembering that the world, as we are about to see, still belongs to the very small. 20 SMALL WORLD ITБЂ™S PROBABLY NOT a good idea to take too personal an interest in your microbes ...» | Код для вставки книги в блог HTML
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