The primitive food chain is mutually exclusive, so that different species can continue to survive in nature, piranhas have a nemesis even if they are fierce.

Water bears are the common name for retarded animals, and these creatures are so small that their body length is usually no more than 1 mm, so we usually do not notice their presence.

Under human domestication, people are more like the head wolf of the pack in the eyes of dogs, and when people are alive, they are absolutely loyal. However, when the "head wolf" dies, this obedience disappears, so there is no difference between the human corpse and the meat of animals in nature in front of the dogs