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Re: live births in birds
JNorton@MAILBOX.UNE.EDU wrote:
> To the best of my lnowledge, live births in birds would be impossible
> because of the structure of bird lungs. <snip>
> If dinosaurs such as sauropods produced live young, they could not
> have avian-type lungs, at least those found in modern birds.
I assume this egg-type is also true of modern Ratites?
So what would have to change to allow this if the eggs are perhaps
leathery, as the really large eggs shown in last months National
Geographic seem to be (look a lot like 2 foot long turtle egg).
Is there a possibility that egg-types have also evolved with birds
since their appearance in teh Jurassic and that more primitive types
could have had the leathery-type as in turtles? Are the
Oviraptor-type eggs found in a hen-egg-type shell, or do they fit more
into a leathery turtle-egg shell?
(I've been assuming the Protoceratop/Oviraptor eggs were more hen-egg
type)
-Betty Cunningham