If the animal kingdom is a school, then there is no doubt that this little fellow is the most popular student. The largest rodent in the world, the water porpoise, seems to get along well with all the friends in the animal kingdom. The puffer fish can grow to about 1.3 meters long and weigh up to 65 kg. As a semi aquatic mammal, capybara is a social animal that likes to gather together. There are about 100 capybara living together in each settlement, most of which live in the forests and swamps of South America. Capybara and other small animals get on well with each other, whether it’s kittens or caimans. Despite their incredible nature, the puffers are gentle and intelligent enough to be kept as pets, as long as they have enough pools and grass and friends to accompany them.