Lopsided waterbuck

From The Telegraph:

Amateur photographer Ingrid Bunse snapped this photograph of a waterbuck with lop-sided horns while on safari in the Ongava Wilderness Reserve, Namibia. She said: "When I spotted this animal I knew I had to get a picture because it was so unusual - I've never seen anything like it. I don't know what caused the horn to curl like this but it didn't seem to be too bothered by it."

It must have been that way a long time, judging by the way the tip of the horn has been burnished during grazing.