Seems like putting the cart before the horse to speculate on the origin of consciousness, or if it may have evolved, and if so, how it evolved, when science has yet to even come up with a satisfactory definition of consciousness, or any way to measure or quantify it.
It is an interesting proposition. Recursive thought basically allows humans to do things like count and have our “inner voice”. This type of thought is not present in animals. So when did it emerge in humans? The author posits 50 to 100 thousand years ago for women and much more recently for men. Perhaps the holocene or even more recently.