Time well spent

Taken together, we show that there are distinct processes by which different squamate species build their lungs. Notably, the luminal pressure-driven stress ball morphogenesis in anoles appears to be derived, potentially due to the fact anoles develop in ovo so much faster than other squamates!

Notably, these structures aren’t being sculpted by smooth muscle like in mammal lungs. Rather, they are enriched for pMLC in the apical region of the epithelium, suggesting an apical-constriction mediated outgrowth. This developmental process is what bird lungs use to branch!

We also found some very interesting aspects of chameleon lung development. Chameleon lungs exhibit multiple chambers and these bizarre projections called diverticulae. These chambers and diverticulae seem to grow out via concentrated cell proliferation.