So, what did kill off the human race in the end?
The end of the movie takes place 2,000 years in the future after all humans are long dead. So, what finally killed off mankind? From one scene with a computer monitor the "present" day takes place in the 2130's. You have advanced tech and (I would assume) a active space program at least mining the moon and asteroid belt for raw materials that were greatly needed. Even if "mecha" were used for space mining / exploration you would think at some point humans would be put on "off world" colonies. So, what kills off mankind?
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