A zebra at Zurich Zoo appeared to be staring into the jaws of death when visitors saw it nose to nose with an open-mouthed hippopotamus.
But the hippo had no intention of having the zebra for lunch – it was having its teeth cleaned.
The extraordinary sight was captured by photographer Jill Sonsteby, from Jacksonville, Florida.
She said the teeth-cleaning session lasted 15 minutes and the zebra came to no harm.
“The zebra was in the same enclosure as the hippo and its baby,” said Ms Sonsteby, 34.
“The hippo opened its mouth and let the zebra in there to clean.
This is that same sort of thing that happens in prisons with male inmates. Only its not the teeth that get cleaned.