Extended Data Fig. 6: Scaling of egg volume with body mass for our sample of extant lepidosaurs.
From: A giant soft-shelled egg from the Late Cretaceous of Antarctica
See dataset 1 in the Supplementary Methods (n = 241); each clade is labelled. The regression line corresponds to a PGLS fit (r2 = 0.6851; P < 2.2 × 10−16). For Antarcticoolithus, estimates of body mass (BM) from both PEMs and PGLS are provided. The PEM estimate is very low for a giant marine reptile of more than 10 m in length (see text), which is probably due to the lack of taxa within the 106 g order of magnitude usually inferred for large marine reptiles. Conversely, the PGLS estimate is surprisingly high, which might be linked to the large gap in egg-volume values between Antarcticoolithus and extant lepidosaurs, as suggested by the similar results we obtained with body-length estimations (Fig. 2, Supplementary Methods and Supplementary Table 1).
