What can "metacognition" in animals tell us about consciousness? Humans are able to feel uncertainty. They know when they know something and when they don't. This capacity for 'metacognition' (thinking about thinking), or cognitive self-awareness, is thought to be one of humans' most sophisticated cognitive capacities and to be linked to our reflective consciousness. One of the important questions in the field of animal and human psychology is whether this metacognitive capacity is uniquely human, or whether nonverbal, nonhuman animal species have a level of metacognition that approaches that of humans.