So I'm one of those weired people who believe that zombie apocalypse is going to occur// I've been reading a zombie survival guide and it explains a lot that would help you. A zombie apocalypse is said to occur every single era// Either the organisms survive the attack or they are entirely consumed therefore causing extinction. The "zombies" are usually infected by a virus called Solanum.. The virus kills every other organ and keeps the brain living. Basically a heart is their brain. Their only living function in their body. Not to mention that zombies cannot feel any pain or emotions. As well as the virus cannot bring a dead body to life it only alters it...I could tell you so much more if you'd like. But if your to embarrassed to ask because (for some reason) you believe this is insane then read the book "A Zombie Survival Guide" composed by "Max Brooks".