An elephantine problem

You might think that zoo animals have a cushy life. They are provided with food and shelter, and don't need to worry about being attacked by other animals. However, they are not free to leave and, despite zookeepers' best efforts, they live very unnatural lives. While some animals live much longer lives in zoos than they would normally, according to the Scientific American elephant lifespans are halved. They even live significantly shorter lives than working elephants employed in logging activities.