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Re: SPECULATION: pterosaur extinction versus bird survival

Demtrios Vital wrote:

 "Pterosaurs also had a less efficient breathing system than

Yeah, [pterosaurs] had an efficient breathing system--but notice I said "less
efficient...than birds." I say this for several reasons. One is the neck
itself. Pterosaurs have notoriously small bodies and very long necks."

Have you considered the efficiency of the respiratory systems in mammals and reptiles? If you hypothesis about pterosaur extinction is correlated with decreasing levels of O2, why would the mammals and reptiles make it through the K/T? Both groups have much less efficient respiratory systems than birds and (presumably?) pterosaurs (although we don't know for sure).

Matthew Bonnan
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