I was scrolling through one of my old featured threads
Inherited sin: yes or no which lead me to this question....do those who believe in evolution also believe they have a soul and if so, at what point in the evolutionary process did we develop a soul?
The Theory of Evolution deals with biology. It deals with how our physical bodies evolve. Spirituality is not addressed in the Theory of Evolution.
However, one can see historically an evolution of how man has experienced and expressed the spiritual historically through the arts, literature, and the views man has evolved culturally. I would argue that spirituality, of which you could include understandings of what the soul is, has always been present by virtue that all life is created by God. It's as my signature says, "Turtles all the way, and all the way down", meaning it is timeless.
At what point did humans begin to recognize that a part of ourselves extends beyond the physical, which is what you can easily understand as a view of the "soul", is the real question. Evidence of burial rites, which shows a belief that the person continues after death, are evidenced back to 300,000 years ago, possibly earlier. What you do see is how these very early understandings of a spiritual reality evolves in the forms and depths it takes, moving from these early archaic expressions, to much later expressions in magic systems, then later expressions in mythic systems, and up into modern rational systems, and continuing on today in other forms. Expressions of these religious forms can be seen today in various religions, and all of these within the same religion due to the fact that people go through stages of development within them.
For instance you have Christians who are very much at the magic stage, believing that pleading the blood of Jesus will bring supernatural results, enacting special powers for them through such incantations. You have those at the mythic stage, which sees God as an external being who takes special notice of the person and sends help from above to favor them. You have those at the rational stages who interpret spiritual matters in terms of rational propositions, such as understanding that symbolism evokes psychological benefits which affect spiritual experience. And so forth.
So in this you see evolution taking place as well. But the spiritual itself, is something innate in all living things. The question from you really is, at what point did we start to recognize it in ourselves. It's not that the soul "evolved" into being. It's always there. It's only a matter of sufficient development for it to begin to be a part of one's own conscious awareness. And that beginning realization goes way back to at least 300,000 years, if not further than that.