Humans aren't intentionally meant to destroy Earth, it's an interesting idea but ultimately not true. It's not in our nature to destroy everything, but rather to be resourceful. It's just that those resources have to come from somewhere and eventually they will be used up if they are not given time to replenish adequately. The meaning of life for all species, including humans, is to continue the species by having offspring.
The meaning of life is to live life to the fullest. There may be obstacles that put us down but we have to break through those barriers to get what we really want and need. I guess you could say the meaning of life is love.
I don't think there is a meaning, but being humans and having the capability to wrap our heads around ideas, we create these theologies and meanings to life, when really, the only reason why anything lives is to make more.