Question: is it valid to refer to the makapansgat pebble as an artwork

Answer: No, The Makapansgat pebble cannot be seen as art if a usual definition of the term is used, as the object was found and not made. Nevertheless that an Australopithecus may have recognized a face would reveal that the early hominid had some sort of capacity for symbolic thinking, necessary for the development of art and language. If the early hominid has seen this object really as a face, or had magical speculations towards this object or just enjoyed the pebble remains unclear.