English: "Fig 20. Size disparity of late Maastrichtian pterosaurs and birds.
Maastrichtian pterosaurs are larger than coeval birds in both marine (blue) and terrestrial/freshwater (orange) ecosystems. Wingspan estimates for pterosaurs are from S2 Data. Wingspans for terrestrial birds were made using estimated masses from Longrich et al. [74] and the equation for passeriformes from Norberg [75] or from reconstructions based on fossils [76,77]."
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75. Norberg UM. Allometry of bat wings and legs and comparison with bird wings. Philosophical Transactions of the Royal Society of London B: Biological Sciences. 1981;292(1061):359–98.
76. Dyke GJ, Dortangs R, Jagt JWM, Mulder EWA, Schulp AS, Chiappe LM. Europe's last Mesozoic bird. Naturwissenschaften. 2002;89:408–11. pmid:12435093
77. Agnolín FL, Egli FB, Chatterjee S, Marsà JAG, Novas FE. Vegaviidae, a new clade of southern diving birds that survived the K/T boundary. The Science of Nature. 2017;104(11–12):87. pmid:28988276