At some point, while I was in graduate school, it became apparent that I was going to study the problem of finding one’s way around. Navigation, orientation, mental maps, sense of direction, knowledge of the landscape, and related ideas must be linked to how people who live off the land survive, and I was studying the foraging ecology of Efe Pygmies in the Ituri Forest. One of the things I realized early on is that it is very easy to find something in the rain forest, as long as one simple thing is true: You already know where it is. Otherwise, you are sunk.

Wait, what does this have to do with tiny compasses in bird brains? Click here to find out.