Aspects of children's early representational drawing ability may provide evidence for feature marking in non-linguistic symbol systems. To test this assumption children in kindergarten, second, and fourth grade were asked to draw a set of referent objects in three conditions: a nominal or standard condition with no implied relationship ("two people,""two dogs," and "two horses") and two contrastive conditions (the same referents talking to or looking at each other). It was predicted that each object would consistently be represented in a specific canonical orientation (front for people and side for horses and dogs) and, at the same time, the side orientation would be used to convey the intended relationships in the contrastive condition. When the object's canonical orientation is at variance with the orientation generally used to convey the intended relationship, then increased difficulty in graphic communication will occur. The results fit the predicted model with the major developmental shift in children's ability to graphically differentiate nominal and contrastive conditions occurring between kindergarten and second grade for drawings of horses and dogs between second and fourth grade for drawings of people. The role played by the canonical orientation is seen as analogous to that of the unmarked term in language acquisition. (Author)