[1] 24341.68 27017.90 67453.38 22114.19 53884.76 52026.34 species lengths masses 1 Stegosauria 18.52588 24341.68 2 Ankylosauria 16.43598 27017.90 3 Ankylosauria 23.73421 67453.38 4 Sauropoda 23.93411 22114.19 5 Ankylosauria 21.68718 53884.76 6 Ankylosauria 21.38363 52026.34 # A tibble: 4 x 2 species avg_mass 1 Ankylosauria 46819. 2 Sauropoda 16104. 3 Stegosauria 31924. 4 Theropoda 45572.