Any animal is divided into two modes of memory: short-term memory and long-term memory, where short-term memory is something that is stored in the animal's brain for only a few seconds, usually such things are arbitrary events for the animal.
Tigers usually rest on the ground. As tigers living in temperate zones, the ability to keep their abdomen warm in winter is a critical factor, so the Northeast tiger has the longest abdominal hair among all tiger subspecies.
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.