Fig. 3 Thin sections and tissue maps of volant birds (a–i). Scale bars are as follows: a (50 μm), b (50 μm), c (100 μm), d (250 μm), e (50 μm), f (100 μm), g (200 μm), h (100 μm), and i (100 μm). Images used from Wikimedia Commons and from the San Diego Zoo Wildlife Alliance.

IOB
"This suggests that #ventilatory air sacs and associated diverticula can be present despite the absence of #osteological and #histologic correlates..."
Byrne et al
doi.org/10.1093/iob/...

#archosaurs #birds #avian #science #biology