Table summarizing muscle mass and fiber length data used to calculate the external forces acting on the upper beak of the different species of Darwin’s finch.

Mass in gram, fiber lengths in mm. N = 1 for all species except G. fortis where N = 4. For the smaller species C. olivacea, C. parvulus and G. fuliginosa the distinction between the medial and lateral superficial m. pseudotemporalis was extremely difficult to make. As such both layers were grouped. Similarly, for the smallest species, C. olivacea, we were unable to extract the m. adductor mandibulae ossi quadrati (MAMOQ). MDM, m. depressor mandibulae; MAMER, m. adductor mandibulae externis rostralis; MAMEV, m. adductor mandibulae externus ventralis; MAMEP, m. adductor mandibulae externus profundus; MAMOQ, m. adductor mandibulae ossi quadrati; MPsTSl, m. pseudotemporalis superficialis pars lateralis; MPsTSm, m. pseudotemporalis superficialis pars medialis; MPsTP, m. pseudotemporalis profundus; MPtVl, m. pterygoideus ventralis pars lateralis; MPtVm, m. pterygoideus ventralis pars medialis; MPtDl, m. pterygoideus dorsalis pars lateralis; MPtDm, m. pterygoideus dorsalis pars medialis; MRPal, m. retractor palatine; MPPtQ, m. protractor pterygoidei et quadrati.
Table summarizing muscle mass and fiber length data used to calculate the external forces acting on the upper beak of the different species of Darwin’s finch.