Soul gets involved in this world of matter. It experiences and learns. Soul then works its way back in a long pilgrimage to its primal source. This again follows a cyclic pattern. This evolution achieves experience, self-awareness, and ever increasing perfection.
Evolution occurs on the physical, mental, and spiritual planes.
The origin of the species is due to intelligent design. There is a seven fold constitution of man ranging from the physical plane to the purely spiritual plane. Thoughts are tangible objects on higher planes. Every thought and action has its effect on us and on our surroundings and has a karmic consequence. At the moment of death we have a review of our life just past - as we cast off this physical frame.