Boxplot showing the distribution of the ratio of the length/width ratio of the parietal for a sample of iguanodontoidean ornithopods. The inserted smaller graph shows the Bayesian information criterion (BIC) for various numbers of clusters in
which the data can be classified. The photograph shows how the two variables of this raio were measured, exemplified in the parietal of Tanius
sinensis (PMU R240). Grey horizontal lines delimit character states.