I ran across an article about this recently. Pretty fascinating.
The science of consciousness has made some strides in recent years, and some information actually comes from more understanding of what happens in the brain when a person or animal is unconscious due to
anesthetic or sleep. The weird conscious state that we experience within sleep--aka dreams--are especially fascinating.
Most of the work has been done on vertebrates, most especially mammals, and for a long time they only thought mammals had dreams. Then they found evidence
in birds. Then
in reptiles (well, birds are fancy and intelligent reptiles, really, so not surprising). Now information about some invertebrates is trickling in. There has already been evidence that
octopi have (brief) dreams. Our neurons all function in pretty much the same way and share a common evolutionary heritage (albeit hundreds of millions of years ago), so it's not that surprising that we would see commonalities.
Surmising the exact subjective experiences of another being is tricky and problematic, of course, but the idea that only humans (or only mammals, or only primates or whatever) experience
emotions or consciousness
has mostly died among researchers. It makes logical sense that we are not alone here, since our feelings and awareness (and need to dream) had to evolve from something. It seems unlikely that it would emerge, fully formed, in a hominin ancestor if they didn't exist (in some form) in our shared ancestors.
of this!
