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Re: Sauroparental care

On Thu, 25 Dec 2003, ANN SCHMIDT wrote:

> First of all, there is the depth at which the eggs are
> buried and the type of nest.  Sea turtles bury their
> eggs a good foot to two feet underground in a habitat
> where once the sand is brought back, it is very hard
> to tell where the nest is.  Sauropods weren't ones for
> delicate work and they didn't have beach sand to dig
> in.

Yes...also, sea turtles have the option of beaches remote from many
terrestrial predators.  In places where racoons and others are predators,
most of the pre-hatching predation is done in the first day after laying,
i.e., when mostly olfactory cues are available.

> Could they really feasibly dig underground nests,
> let alone in a colony, and pack the ground down to
> where the nest was not noticeable, without crushing
> the nest or leaving the area so denuded, full of
> footprints and droppings that anything going past
> would recognize that the sauropods had been there?

Certainly not.

> Thirdly, there is the number of eggs.  The sauropod
> clutches were a few dozen at most right?  Sea Turtles,
> even the small species, all lay over fifty to over two
> hundred eggs per clutch and several cluthes per season
> at that.  Thus the glut of hatchlings from saurpods
> could not equal that of relatively small sea turtles.
> A bad strategy in a world where every predator large
> and small comes to wherever a glut of defenseless
> hatchlings are.  Even lions will eat, or attempt to
> eat in the case of ostrich eggs, egg if there is an
> opportunity.

Thanks mostly to grass and its ability to provide food and
concealment in a semi-arid (i.e, low predator density) environment,
ostrich nests are _very_ hard to find.  Those that are found are

> It would be a simple matter for a large
> theropod to dig away at a nest and gulp down the
> massive nutrition the eggs would give in a few bites.


> Destroying surrounding vegetation could be easily
> avoided as well.  Aside from fasting there is the fact
> that only a few sauropods from any herd needed to stay
> at the nest colony at any one time to protect the
> young, just like many modern days animals only leave a
> few babysitters.  The rest of the herd could go off
> miles away and feed, other individuals switching out
> with the babysitters routinely.

Emus have the incredible ability to shut down metabolism and sit on the
nest for around two months w/out food or water.  Perhaps sauropods both
reduced metabolism and nested near lush, highly productive forests.  Who
knows?  The point is, I think, that nest attendance cannot be ruled out
with such an argument.

> I doubt that baby sauropods traveled with the herd for
> many reasons.

A crop of baby sauropods moving through a predatory gauntlet of at least
three years among serious predators?  My guess is that mum and dad would
offer the best protection around.

> Sea turtles these creatures were
> not.

Aye, aye, Capn!