from IN SEARCH OF MEMORY by Eric R. Kandel:
"....each mental function in the brain - from the simplest reflex to the most creative acts in language, music, and art -- is carried out by specialized neural circuits in different regions of the brain...all of these circuits are made up of the same elementary signaling units, the nerve cells. (These) neural circuits use specific molecules to generate signals within and between nerve cells...(And) these specific signaling molecules have been conserved - retained as it were-- through millions of years of evolution. Some of them were present in the cells of our most ancient ancestors and can be found today in our most distant and primitive evolutionary relatives: single-celled organisms such as bacteria and yeast and simple multicellular organisms such as worms, flies, and snails. These creatures use the same molecules to organize their maneuvering through their environment that we use to govern our daily lives and adjust to our environment.
Thus, we gain from the new science of mind not only insights into ourselves--how we perceive, learn, remember, feel, and act--but also a new perspective of ourselves in the context of biological evolution. It makes us appreciate that the human mind evolved from molecules used by our lowly ancestors and that the extraordinary conservation of the molecular mechanisms that regulate life's various processes also applies to our mental life.."
So after millions of years of evolution how is that all we have to show for ourselves is :