I don't think this was even signed during my previous visit. I recall them Schmutzer Primate Centre once display crab-eating macaques and southern pig-tailed macaques in one of these exhibits. Perhaps this one would house either one of them in the future.
@Rizz Carlton I really enjoyed the Primate Center and @twilighter and I spent a full two hours just in this part of the zoo. It requires a separate fee, but it's worth it!