every single creature on earth has not evolved or has not been given the ability to survive without sleep, and all animals that are lesser than the human have to be regularly treated for bacteria than can seriously hurt them. there are very few diseases that have a 100% casualty rate if a human gets it, but there are many for every kind of animal. but does that separate them from lesser animals? no, a human’s immune system is simply far too advanced for bacteria that can only affect lesser animals. so certain and most bacteria instead of harming a human being directly, can cause them to develop neurological disorders.