FIGURE 4. Stacked plots showing the relative proportions of the ulna, femur, and tibia of Rahonavis ostromi compared to (1) avialan and (2) non-avialan theropods. In each set of plots, the taxa are organized, left to right, from shortest to longest relative ulna. Aurornis and Anchiornis are considered basal avialans in Godefroit et al. (2013a) and Lefèvre et al. (2014), but non-avialan theropods in Brusatte et al. (2014) and Lefèvre et al. (2017). Cau et al. (2015) placed Anchiornis as a basal bird but Aurornis as a theropod. See Table 1 for measurements.