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Airsacs for everyone?
Topic Started: Oct 12 2009, 05:11 PM (273 Views)
Carlos
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Adveho in me Lucifero
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Pulmonary airsacs evolved at least three times in sauropsids: in dinosaurs (if pterosaurs are their closest relatives then in the last common ancestor between them), drepanosaurs (again, if pterosaurs turn out as being their closest relatives as some workers have proposed...) and sea snakes. This, of course, assuming that dinosaurs (and pterosaurs?) and drepanosaurs (and pterosaurs?) evolved airsacs independently, because for all I know they could just had been present in their last common ancestor and then subsequently lost in crurotarsans like crocodillians.

Since airsacs would have evolved a couple of times among reptiles, maybe synapsids could be able to produce an airsac pulmonary system too. Should our ancestors had opted for a very efficient pulmonary system like that instead of our flawed diaphragm, maybe things would have gone very differently. For starters, dinosaurs would never have evolved since the advantage of more advanced lungs wouldn't exist at all.
Lemuria:
http://s1.zetaboards.com/Conceptual_Evolution/topic/5724950/

Terra Alternativa:
http://s1.zetaboards.com/Conceptual_Evolution/forum/460637/

My Patreon:

https://www.patreon.com/Carliro

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Holben
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Rumbo a la Victoria

I didn't know that. Thanks.
Time flows like a river. Which is to say, downhill. We can tell this because everything is going downhill rapidly. It would seem prudent to be somewhere else when we reach the sea.

"It is the old wound my king. It has never healed."
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