Survival of the fittest is basically the surivival intinct and thus selfishness. Why does an organism evolve and adapt? So it can live long, better, reproduce easier. Kill off the others and any competition, that's what it is.
Where was I going with that?
Ignore this survival instinct, and kill yourself because the world is suffering. Humanity does nothing good for the world, we only harm it. If we kill off ourselves now, we can preserve the world for future generations of organisms and their evolution. Scientifically, the world has existed for 4.5 billion years, life has existed on it for 3.7 billion years. In just the millions of years since the homo genus has arrived, and in the just thousands of years since the homo sapiens have started creating civilization, the very face of the earth has changed, the atmosphere has been totally fucked up. Science may evolve fast, but so does our desecration of the earth. The last thousands of years, what about the next thousand, the next hundreds, hell, how about the next couple of decades? Humanity's prescence is just too much with 6-7 billion people. How does one solve this? Death.