[ WP ] Tell the story of Mitochondrial Eve , but give a sci-fi explanation for why only her descendants have survived .

The sky above the port was the color of television, tuned to a dead channel. How little it resembles the drab, mottled grey of my world's sky. 
 
 I should n't be surprised. So little of my world is unsullied by Man's hand. This natural, clear blue sky is so unfamiliar that it's become preternatural. 
 
 Then again, that's the reason I'm here. The four species of Man, driven by inter-species conflict, are burning through the world's resources -- burning through the world itself -- far too quickly. I'm convinced that there is nothing in the modern age that can reverse the damage. Another ice age is inevitable. No human on Earth can save us. Our whole Genus faces doom. 
 
 We need a human that is no longer on Earth. Someone who is n't part of our modern age. 
 
 
 Where better to look than a hundred thousand years ago? 
 
 
 There is a species that did n't make it to the modern age. Some eighty to ninety thousand years ago, there was another, failed branch of genus Homo. Recent evidence suggests that something more than mere competition with its Neander/Thall contemporaries drove it to extinction. My Neander and Thall contemporaries wo n't even give the question a moment's thought. Why would they? They know that they won evolution's contest. It takes a Denisovan like me to care about losers. 
 
 Temporal ports are small. I can barely fit a decent optic nanocable through. There's no way to pull resources from the past. I might be the only one who's ever thought of putting something into the past. After all, what microscopic deposit could anyone possibly make that would give himself an advantage today? It just ca n't be done. 
 
 But, I can give away a random advantage. I can help the meek inherit the Earth -- give some other loser a chance to fight longer. It was n't just technological competition with the ancestors of Neander and Thall that drove Homo Cromag past the brink. Early contact also led to an exchange of diseases. Neander/Thall brought a pox upon Cromag. 
 
 All I need to do is infect one Cromag child that can carry and spread the weakened blackpox retrovirus. One live inoculation, and perhaps the world changes. 
 
 
 Let's see how happy my Neander overlords become once they've had to face a little healthy competition.
