I like it... Why would you have to put up a sign that says that? That doesn't make any sense. Unless all the natives are half people and half horse or something... I wonder what the motivation for putting up a sign like that is.
On the internet I once saw a low-hanging sign above an escalator that says "Please watch your head, as this sign hangs pretty low." Then a diagram of a guy riding an escalator ducking, and one not ducking with the little dude getting hit. Then next to it there was an arrow shaped sign reading "Please read that sign." It was probably a photoshop but it made me laugh.