Hippopotamus Yawning in Shallow Water

Hippos don't sweat. Their skin oozes a thick, oily fluid that starts out clear and turns red and then brown in the sun, which gave rise to the old idea that they sweat blood. It works as a sunscreen and seems to keep wounds clean too. Half in a muddy river, this one throws its jaws wide open in a hippo jigsaw puzzle with pink skin, long tusks and wet gray hide. Few animals can open their mouths quite this far.