Lets take religion out of the question for a moment, scientifically speaking, why am I conscious in this body, and not another one? Why was I born now, and now 10 years earlier? 

The brain is connected to consciousness in ways we do not comprehend.Did you guya know thoughts are immaterial? I believe our souls are the true essence of consciousness. The brain chemicals cant be the source of our being because we would have discovered it by now if observable. Someone in a coma whose brain dead is still there spirtually.
Food for thought.