Novel insight into the origin of the growth dynamics of sauropod dinosaurs
(A, B) General view of the external cortex in normal transmitted (A) and polarized light (B). Note the predominance of well organized intrinsic fibers in the unaltered portions of the sample (bright areas of the outer cortex in B). Arrowheads indicate the presence of LAGs. (C) Detail of the primary bone tissue showing well organized intrinsic fibers and flattened osteocyte lacunae. A growth line (arrowhead) and several Sharpey’s fibers are also observed. Polarized light. (D) Enlarged view of the outer cortex showing a distinctive variation in the vascularization pattern in the compact bone. Such variation starts just above the last preserved LAG (arrowhead). Polarized light with lambda compensator. (E) LAGs (arrowheads) formed in the outer cortex. Normal transmitted light. (F) detailed view of the last six LAGs (arrowheads) formed in the outer cortex. Note the scarce vascularization of the outermost region. Polarized light with lambda compensator. Abbreviations: Sf: Sharpey’s fibers.