I can imagine a world where consciousness doesn't exist at all. Why does evolution allow for consciousness instead of zombie like animals?. This has always got me thinking. You could say that natural selection chooses consciousness over being a zombie because it's all about reproducing. Well that seem like a short sighted answer. I mean why all this subjective qualities that apparently consciousness has?. Plus I can easily imagine a different direction of evolution where reproduction is not the main goal.
This is one of the arguments that a materialist fails to answer instead they try to turn it around by saying why do you need a brain if consciousness can do it all?. Well, first of all consciousness uses the brain as a interface for consciousness and mind. I remember neurologist Steven Novella mentioning to me that specific structures effect consciousness. Well specific parts of your television cut off channels in your television set. The hard problem of consciousness is how can you explain the subjective feeling of consciousness. This inner life experience that we all internally experience. How can the brain give rise to subjective experience?.
This is far from an easy question to answer some believe there is really is no hard problem at all like neurologist Steven Novella. Which of course leads to pure denial. While, other honest scientists admit their is a serious problem here and there is right now no good working theory to account for consciousness. However, I think there is many scientists are most likely however are not aware of the transmission theory of the brain. If they were as well as the evidence in favor of it they may be willing to heavily consider it as a theory that can account for consciousness with how it relates to the brain.
On a side note, there is a recent video on skeptiko, that is very interesting. "Can materialistic science answer life's big questions?".
http://www.skeptiko.com/can-science-answer-big-questions-317/
Also, an excellent paper on "The Soul Hypothesis: Investigations into the Existence of the Soul".
https://ndpr.nd.edu/news/24611-the-soul-hypothesis-investigations-into-the-existence-of-the-soul/
