Humanity is absolutely fucked . The Aliens novel , Earth Hive . actually goes over this , and this is with a black ops military groupgovernment who was aware of the Xenomorph threat . What happened was that they would respond immediately to any signs of sudden mass disappearances , track the hive and take it out , but the aliens soon adapted . What was once large hives with dozens of eggs would be tiny hives with a dozen . A major issue was rural areas . Farmers and their livestock might not be reported on time . Things got worse when the aliens found their way into jungles and the arctic , where it was nearly impossible to track them and they multiplied exponentially . Another issue was the firepower needed to kill them . They ' re nearly immune to low caliber rounds and idealy needs armor piercing high explosive ammo to reliably kill , as the ammo would destroy them from the inside . This basically means that civilians are screwed against them .