Are there any animals self-aware enough to question their ability to think?
That's hard to say. Animal research appears to indicate the self-awareness of higher functioning animals is very Zen-like, that is, focused on their experience of the moment without much judgement.
The traditional test for self-awareness in animals is their ability to recognize themselves in a mirror. Few animals pass the test - primates, like gorillas, chimps, orangutans and rhesus monkeys; plus, orca whales, bottlenose dolphins, elephants, crows and ants. Human babies develop this ability between the ages of 14 and 18 months.
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