Well if it was good science fiction she would discover that the microbial life on mars made it to earth after a meteor impact and by virtue of acting as a virus, infecting pregnant apes who gave birth to what would be recognized as humans. And that human activity on Mars doomed it to extinction, and human activity on Earth doomed <i>humans</i> to extinction, and so we not only killed off ourselves, we kill of our chance to evolve again on earth.<p>Of course that would be a real downer of a story.