SEM of demineralized bone matrix from multiple specimens. (a) Fresh chicken showing fibre bundles. Crossbanding is not within SEM resolution capability. (b) Emu matrix, with fibre bundles at higher magnification. (c) Moa trabecular bone (MOR OFT255). (d) Mammoth (MOR 91.72). (e) Mammoth (MOR 604). (f) Mastodon (MOR 605). Featureless matrix is impossible to image without also imaging osteocytes (centre). (g) Tyrannosaurus rex (MOR 555). (h) Tyrannosaurus rex (FMNH-PR-2081). (i) Theropod indeterminant (MN 4802-V). Magnifications and scale bars are as indicated.