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Re: egg meanderings while on cough medicine
>Why does size of a saurapod mean live-bearing? What am I mising here?
I believe live-bearing in sauropods has been supposed because
of the assumed (large) size of the sauropod embryo/hatchling. The
idea is that the egg would have to be fairly large, and accordingly
the shell would have to be relatively thick. If this is the case,
then gas permeability becomes a factor limiting eggs to a maximum
size. Ostensibly, this size is to small to house a baby sauropod.
Furthermore, fossil eggs have been very hard to associate with
sauropods. As far as I know, there is no clear evidence for sauropods
laying eggs. There is a new paper on a sauropod nesting site, but I
haven't read it yet. (S.K. Tandon & A. Sood & P.F. Dennis, 1995,
"Palaeoenvironments of the dinosaur-bearing Lameta Beds
(Masstrichtian), Narmada Valley, Central India," Palaeogeography,
Palaeoclimatology, Palaeoecology 117(3/4):153-84.) Part of their
The Lameta Beds are well known for sauropod nesting sites and
sedimentological analyses of these sites suggest that the animals
selected topographic highs, usually in marry or sandy, soft sediment.
Multiple nests with similar egg types probably indicate colonial
nesting. Isotopic analyses of eggshell carbonate agree with earlier
work suggesting that the sauropods ate a ''C3'' plant.
That sounds like evidence for sauropod eggs to me, but I'm
sure someone on the list knows a lot more about this than I do.