Facts about viruses

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  • Viruses are not alive: They do not have cells, they cannot turn food into energy, and without a host they are just inert packets of chemicals.

  • Viruses are not exactly dead, either: They have genes, they reproduce, and they evolve through natural selection.

  • Viruses are already known to infect animals, plants, fungi, protozoa, archaea, and bacteria. Sputnik and Mamavirus suggest that they can infect other viruses, too.
 
  • In fact, scratch the whole concept of “us versus them.” Half of all human DNA originally came from viruses, which infected and embedded themselves in our ancestors’ egg and sperm cells.
     

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