Consciousness could not have evolved from “simpler” states of matter, because it is not a state of matter. To say that consciousness evolved from matter is like saying Newton’s theory of gravity evolved from apples.
Even if for the sake of argument one concedes that natural selection might account for the development of a material body, consciousness remains a mystery. There is still a vast un-crossable gulf between the physical body and mind. In other words, the difference between body and mind is qualitative, not quantitative. You can’t get an immaterial mind no matter how many slight successive modifications of the body there may have been.
David Bentley Hart puts it this way:
It makes sense to say that a photosensitive cutaneous path may be preserved by natural selection and so become the first step toward the camera eye;* but there is no meaning-sensitive or category-sensitive patch of the brain or nervous system that can become the first step toward intentionality, because meanings and categories are not physical things to which a neural capacity can correspond, but are instead products of intentional consciousness.
*It really doesn’t as has been explained in these pages, but we will grant it for the sake of argument.