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I teach anatomy and sometimes I introduce a topic by looking at that same structure in other organisms, especially from an evolutionary stand point. I have two questions - are bird lungs "better" than ours because they have additional air sacs or reservoirs that allow gas exchange while they are exhaling as well as inhaling,
or are the tiny alveoli found in human lungs actually more efficient because there is more surface area for gas exchange.
Its funny how you get in the habit of assuming humans are top of the line evolution wise. I have to remind myself that an eagle's eyes are sharper than mine. In reptiles, dinosaurs vs alligators, they talk about uni-directional or bi-directional air flow - does that mean air flows out a different way than it came in?
What structure allows this? Or are they refering to those same kind of air reservoirs found in birds? They implied that reptiles like alligators, and birds, survived better in a lower oxygen environment, but it looks like dinosaurs had lungs more like mammals, so I dont get it. Unless all mammals were just smaller and could get by for a while.