It’s no secret that primates are intelligent. In fact, they have been taught to communicate with humans via sign language since the 1960s. Yet, in all that time, the apes have never asked a single question. Some primates have developed a vocabulary anywhere from 1,100 signs up to 6,000. Researchers have worked with primates to communicate about complex topics like emotions and past experiences, but it seems that apes are still missing one thing: the ability to ask questions. It’s possible that apes can ask questions but just haven't been interested enough to do so, but extensive research has yet to show that. Maybe it’s just one of those things that sets humans apart from the rest.
