Introducing consciousness as such adds nothing to the explanation of why a living organism acts this or that way. Let's look at the argument of the following kind "Consciousness gives a species an ability to evaluate its situation and take appropriate action". If we explain consciousness as an effect of the workings of the brain and body, then we already have an explanation, namely the workings of the brain and body. Calling it consciousness is not necessary, and adds nothing of value to our explanation.

Just like if you have a computer and its program. It can be very intricate, memorize things, retrieve old information from its memory, compare it to the input which it presently deals with, evaluate, process intelligently, and take appropriate action. If someone asks, "how come it reacted in such a wonderful way to the situation?", we will be able to explain it all by analysing the mechanisms of the computer and its programming, whether that computer has been gradually improving its own programming or not. Our explanation will not be better if we say "this is because it is actually conscious and can reflect on its own situation, etc...". That adds nothing of value to our explanation. Either we understand the structure of the computer and its software or we do not. If we do, then we can explain it from there, with no need to talk about consciousness.

I am not saying that there is no such thing as consciousness. I am conscious, and I assume you are too. The reason I emphasize the above is that I find it important to view consciousness for what it actually is, and not confuse it with intelligence or so. I have written about a similar topic in relation to evolution. I think that approaching the concept of consciousness in this way is sound and that it captures the idea of consciuosness in a way similar to what many ancient traditions do when they recommend meditative processes for understanding awareness and the self.