All living beings have souls. However, not all living beings have personal souls, souls that possess the capacities of thinking and choosing, souls that give life to persons. The soul of a plant is merely vegetative. It enables the living organism to do only the vegetative functions. A plant takes nourishment, grows, and gives off waste. An animal possesses a sensory soul that enables it to perform the vegetative functions—which a plant can do—as well as the functions of the senses. Most animals see, smell, taste, hear, and touch. They have a memory and an imagination, and can move. The personal soul, unique to man, has all the vegetative and sensory functions, and also the personal ones. A human person has a mind and a will, powers of the personal soul, that enable him to think and to choose.
There could never be a human person without a personal soul. Thus, if Christians choose to accept the theory of evolution, they still would believe that when a suitable body had evolved, God infused into that body a personal soul. In other words, by giving man a personal soul, God gave him life and made him into the divine image and likeness—as distinct from all other bodied beings in the universe. Further, God’s creation of personal souls continues today. Every time a human being is conceived, God creates a personal soul that gives life to a human body.