Most of the exhibit was "meh" but I liked this.

Male and female, grim or surprised.  They seem to be arrayed in one of the few possible ways which doesn't seem systematic.*  

The exhibit was called, Alfredo Boulton: Looking at Venezuela, 1928–1978

*I went through a dozen permutations (out of 24 possible) and each systematic one could be matched with a cognate unsystematic version.