As there were no dentaries sufficiently preserved to allow definitive distinction of large- and small-form individuals, it is not possible to separate isolated teeth into form class. However, the means of Myall Creek Diprotodon cheek teeth are similar to the undifferentiated size class samples from the Darling Downs and Lake Callabonna (Tables 2, 3). Additionally, the morphometric range of tooth sizes encompasses that of both large- and small-form individuals of body size differentiated assemblages (e.g. Darling Downs and Lake Callabonna; Figs 14, 15). Thus, those observations are in agreement with those of Marcus (1976), and suggest that both Diprotodon size classes are represented in the Myall Creek assemblage. Additionally, there are no consistent morphologies sufficient to warrant distinction of more than one morphospecies in the assemblage. Therefore, the data suggest that a single, sexually dimorphic Diprotodon species is present in the Myall Creek assemblage.

Coefficient of variation values of the Myall Creek Diprotodon assemblage, and extant grey kangaroos, are lower than that for the Darling Downs and Lake Callabonna Diprotodon assemblages (Tables 2–4). Thus, the data may suggest that the temporal sampling range of the Myall Creek assemblage was less than that for the Darling Downs and Lake Callabonna.