In December, 2004, rescuers saved a baby hippopotamus after his family washed out to sea in a tsunami on the eastern coast of Africa. After being placed in a pen at the Haller Park Animal Shelter in Mombasa, Kenya, the baby hippopotamus (named Owen after his rescuer) hid behind a 130-year-old male Aldabra tortoise, named Mzee. Owen then followed Mzee around their enclosure, licking his face occasionally, reported the BBC.
Eventually, caretakers separated the two and introduced the growing hippo to his own kind. Like the piggyback-riding macaque in Japan, the hippo and tortoise pair became the subject of a booK: "Owen and Mzee: The True Story of a Remarkable Friendship."