The name Hippopotamus comes from the Ancient Greek ‘river horse’. Hippos bask on the shoreline and secrete an oily red substance, which gave rise to the myth that they sweat blood. The liquid is actually a skin moistener and sunblock that may also provide protection against germs.An adult Hippo needs to resurface every 3 – 5mins to breathe. The process of surfacing and breathing is automatic, and even a hippo sleeping underwater will rise and breathe without waking.