Captives

In [popular photography of wild animals], animals are always the observed. The fact that they can observe us has lost all significance. They are objects of our over-extending knowledge. What we know about them is an index of our power, and thus an index of what separates us from them. The more we know, the further away we are.

-- from Why look at Animals? by John Berger (1977). In a zoo, he says, you are looking at something that has been rendered absolutely marginal.