When it comes to consciousness, one of the top challenges is defining what it is. (Some insist it doesn’t even exist, which makes defining it even more of a challenge.) Part of the problem is that there is no single correct definition. There never really has been.
There is also that there is sentience (essentially the ability to feel pain as pain) and there is sapience (roughly: wisdom). Lots of animals are sentient, but sapience seems to be a property of human consciousness.
Which raises the question: Are humans just a point on a spectrum, or is there some sort of “band gap” between higher and lower forms?