It was only recently when it was ascertained that such activities in fact prevent boredom in animals, thereby enhancing their overall well-being. Toys, and sometimes even televisions, are provided by zoos to some animals to prevent them from being weary and restless. In some zoos, monkeys are made to solve puzzles so they can get at their food. The prevailing inclination in zoos today is the doing away with large animals (such as elephants and lions) in favor of the smaller species which can naturally form a distinguishable localized population that can easily be exhibited in zoos. Other zoos have developed a system of reversing night and day conditions to put on display various nocturnal animals. Certain animals are likely to stay within the confines of zoos because of the relative
ease of keeping
and feeding them.