Earlier quoted context omitted.
Obviously viruses are not intelligent and they don't "want" to reproduce. However, they do reproduce, just like pretty much every other form of life. The question of why life does that is closely related to the question of what life is and how it came to exist. Those are deep questions and we don't really have a clue as to the answer right now. There's certainly nothing in the fundamental physical laws of the univers…
What if life is just an accidental misshapen rock which spreads itself changing constantly to adapt to ever hostile environments. OMG What if we're the cancer of the universe, who is in itself a giant amoeba!??!!?!?!? deep thoughts, with jack handy
Sometimes in half-seriousness we say that man may have been evolved by the system as a mechanism to get the fossil fuels and other minerals back into circulation. We hope he is pre-adapted for other roles after that.
From Environment, Power, and Society.
An analog I use is to opportunistic benthic whale fall communities. The emerge and develop rapidly. They do not sustain.