Over five billion years ago gaseous dust and ice poured forth from the afterbirth of a star. Like blood, they clotted together, becoming more dense, until they accreted into the beating hearts of the planets. The earth, whose crust was molten, cooled to a solid surface as the planet accumulated a watery atmosphere. Scientists hypothesize that about half a billion years later, a massive meteorite bombardment slammed into the planet, depositing, amongst other things, ammonia. Nitrogen is a base element of ammonia gas, a substance early earth is not known to have in much abundance, but has recently been discovered in quantities in early meteorites.
Nitrogen is also one of the basic elements of life, forming the backbone of amino acids and nucleotides, which are themselves the building blocks of proteins and DNA and RNA,
respectively. After the shower of meteorites deposited heavy amounts of ammonia in our atmosphere, somewhere -- likely in a shallow pool of water near a volcanic vent -- an abiotic chemical reaction occurred, synthesizing ammonia, hydrogen sulfide, and carbon monoxide to produce the necessary components for a primitive RNA which would form the beginnings of an early metabolism.
Viruses, which are not considered truly alive, are today believed to be the descendants of these early proto-organisms. Tiny replicators, these strands of protein are normally classified along a vertical spectrum beginning with human beings down to the most simple one-celled bacteria, the anorganic process of crystal formation, and the world of dead-matter.