Question: Why do you think only humans, out of all the primates, have evolved to be that bit smarter? Or do you think that they, in time, will evolve like we did?

Duncan McNicholl answered on 15 Nov 2017:

It’s important to remember that we haven’t evolved *more* than any of the other animals, we’ve just evolved differently. I can’t hang upside down out of a tree by my feet and tail, and a capuchin monkey can’t come up with the idea of taxes. Actually, I think the monkey wins on both of those: maybe they’ve evolved more.
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There’s an interesting addendum here, which is something called the “weak anthropic principle”, which says something along the lines of “a question about how we came to be can only be asked by something that is capable of answering questions”. The reason that we’re the ones that are a bit smarter is that being a bit smarter is what you need to realise that you are and start asking about it, so it has to be us that we’re talking about. Well done if you followed that, by the way: I’m not sure I did.