[Modernman]

There is only one species with the capability to ensure that it survives the total annihilation of the planet itself. Guess which one that is?

Viruses?

[contemplator]

Funny you should mention viruses.

Native Americans had no defense against viruses unlike the Europeans who had been struggling with them for some time and had evolved resistances. Viruses wiped out entire tribes, leaving the Europeans with strength of numbers and allowing them to take over easier. In other words, a form of natural selection.