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Re: Meter-wide "dinosaur" eggs reportedly found in Chechnya

Mike Taylor <mike@indexdata.com> wrote:

> Alexander (1989:156-157) touches on this in The Dynamics of Dinosaurs
> and Other Giants.  He doesn't give a number or even a range for the
> size limit due to respiration issues, but does say "even elephant
> birds were probably a long way from that limit".  (At 30 cm in length,
> they are the largest known eggs.)  He also suggests that elephant-bird
> eggs may be near a different limit, in that the shells of eggs much
> larger would have been too thick for the chicks to hatch, but no
> numbers are given.

Maximum egg size is also offered as a possible reason why the enormous
Australian dromornithids (such as _Dromornis_) didn't get even bigger.
 Either that, or a larger body mass was limited by metabolic
constraints, specifically the need to support an elevated, avian-level
metabolism based on low-energy browse.  Both these reasons appear in
the "Magnificent Mihirungs", as possible explanations for why
dromornithids (mihirungs) lost out to large marsupials like the
diprotodontids that were able to surpass the dromornithids in mass.

> No doubt others have looked into this in greater detail, but sadly
> Alexander gives no references.

I've yet to find a reference.  Not one that provides quantitative data, anyway.