Consciousness is restricted to a subset of animals with relatively complex brains. The more scientists study animal behavior and brain anatomy, however, the more universal consciousness seems to be. A brain as complex as the human brain is definitely not necessary for consciousness. On July 7 this year, a group of neuroscientists convening at Cambridge University signed a document officially declaring that non-human animals, “including all mammals and birds, and many other creatures, including octopuses” are conscious.
Humans are more than just conscious—they are also self-aware. Scientists differ on the difference between consciousness and self-awareness, but here is one common explanation: […] To be conscious is to think; to be self-aware is to realize that you are a thinking being and to think about your thoughts. […]
Numerous neuroimaging studies have suggested that thinking about ourselves, recognizing images of ourselves and reflecting on our thoughts and feelings—that is, different forms self-awareness—all involve the cerebral cortex, the outermost, intricately wrinkled part of the brain. The fact that humans have a particularly large and wrinkly cerebral cortex relative to body size supposedly explains why we seem to be more self-aware than most other animals.